Lindane and propoxur residues in cocoa from Central region of Ghana

Lindane and propoxur residue levels in cocoa samples taken from the Central Region of Ghana were determined. Propoxur and Lindane residues in cocoa were extracted by continuous soxhlet extraction with a 1:1 v/v acetone-chloroform and acetone-hexane (20:80 v/v) mixture for propoxurand lindane respectively for 12 h. The extracts were passed through preconditioned octadecyl (C-18) columns to clean up. The pesticides were then analyzed by gas-liquid chromatography using Flame Ionization Detector (FID) and Electron Capture Detector (ECD) for propoxur and lindane respectively. The concentration range for lindane in cocoa was 0.055 - 3.318 mg/kg. The concentration range for propoxur was 0.001 – 0.991 mg/kg. The mean of lindane in cocoa beans were: 0.411 mg/kg, pod 1.113 mg/kg, testa 0.609 mg/kg , placenta 0.905 mg/kg, leaves 0.892 mg/kg and bark 1.332 mg/kg. The mean concentrations of propoxur in cocoa were: beans0.235 mg/kg, pod 0.235 mg/kg, placenta 0.276 mg/kg, leaves 0.104 mg/kg, bark 0.491 mg/kg. From the studies it may be preferable to use propoxur for control of pests in cocoa

Analysis of photographic records of coal pyrolysis. Final report

Bituminous coals upon heating undergo melting and pyrolytic decomposition with significant parts of the coal forming an unstable liquid that can escape from the coal by evaporation. The transient liquid within the pyrolyzing coal causes softening or plastic behavior that can influence the chemistry and physics of the process. Bubbles of volatiles can swell the softened coal mass in turn affecting the combustion behavior of the coal particles. The swelling behavior of individual coal particles has to be taken into account both as the layout as well as for the operation of pyrolysis, coking and performance of coal-fired boilers. Increased heating rates generally increase the amount of swelling although it is also known that in some cases, even highly swelling coals can be transformed into char with no swelling if they are heated slowly enough. The swelling characteristics of individual coal particles have been investigated by a number of workers employing various heating systems ranging from drop tube and shock tube furnaces, flow rate reactors and electrical heating coils. Different methods have also been employed to determine the swelling factors. The following sections summarize some of the published literature on the subject and outline the direction in which the method of analysis will be further extended in the study of the swelling characteristics of hvA bituminous coal particles that have been pyrolyzed with a laser beam

Next-generation ophthalmic diagnostics

We are developing a fully automated mobile application (app) to test for contrast sensitivity by measuring the ability of the patient to follow a moving dot on a digital screen. The test results are evaluated automatically using algorithms that measure the gaze direction of the user. Here we present preliminary results of the app development

LINDANE AND PROPOXUR RESIDUES IN COCOA FROM CENTRAL REGION OF GHANA

ABSTRAC

Measurement of the plasma levels of antibodies against the polymorphic vaccine candidate apical membrane antigen 1 in a malaria-exposed population

<p>Abstract</p> <p>Background</p> <p>Establishing antibody correlates of protection against malaria in human field studies and clinical trials requires, amongst others, an accurate estimation of antibody levels. For polymorphic antigens such as apical membrane antigen 1 (AMA1), this may be confounded by the occurrence of a large number of allelic variants in nature.</p> <p>Methods</p> <p>To test this hypothesis, plasma antibody levels in an age-stratified cohort of naturally exposed children from a malaria-endemic area in Southern Ghana were determined by indirect ELISA. Titres against four single <it>Pf</it>AMA1 alleles were compared with those against three different allele mixtures presumed to have a wider repertoire of epitope specificities. Associations of antibody levels with the incidence of clinical malaria as well as with previous exposure to parasites were also examined.</p> <p>Results</p> <p>Antibody titres against <it>Pf</it>AMA1 alleles generally increased with age/exposure while antibody specificity for <it>Pf</it>AMA1 variants decreased, implying that younger children (≤ 5 years) elicit a more strain-specific antibody response compared to older children. Antibody titre measurements against the FVO and 3D7 AMA1 alleles gave the best titre estimates as these varied least in pair-wise comparisons with titres against all <it>Pf</it>AMA1 allele mixtures. There was no association between antibody levels against any capture antigen and either clinical malaria incidence or parasite density.</p> <p>Conclusions</p> <p>The current data shows that levels of naturally acquired antigen-specific antibodies, especially in infants and young children, are dependent on the antigenic allele used for measurement. This may be relevant to the interpretation of antibody titre data from measurements against single <it>Pf</it>AMA1 alleles, especially in studies involving infants and young children who have experienced fewer infections.</p

Targeted delivery of probiotics to enhance gastrointestinal stability and intestinal colonisation

The aim of this work was to assess the viability of some commercial probiotics after exposure to gastric acid and the possibility of modifying these formulations for delivery into the distal parts of the intestines. Gastrointestinal tolerance testing was conducted for three commercial probiotics and an in-house freeze-dried Lactobacillus acidophilus strain. The contents of the commercial products and the in-house freeze-dried strain were then loaded into capsules for site-specific delivery into the colon using the Phloral(®) coating technology; the viability upon release was then ascertained. An assessment of the potential of these products to adhere to intestinal cells was also conducted. The results showed that all the commercial products contained the minimum number of probiotic strains as indicated on their respective packages. When gastric acid tolerance tests were performed on these products, all the commercial probiotics and the prepared freeze-dried strain demonstrated over 10(6) CFU reductions within 5min. When these were encapsulated for site-specific delivery into the distal parts of the gut, viabilities of approximately 90% were obtained after these capsules had been initially deposited in gastric acid for 2h. An evaluation of the ability of the probiotic formulations to adhere to intestinal cells demonstrated adhesion in the range 64-76% for the products evaluated. The need to target the delivery of probiotics into the intestines has been demonstrated here as this offers a greater potential for colonisation of the intestines once the harshness of the stomach has been overcome

Psychosocial stressors among Ghanaians in rural and urban Ghana and Ghanaian migrants in Europe

Psychosocial stressors have significant health and socio-economic impacts on individuals. We examined the prevalence and correlates of psychosocial stressors among non-migrant and migrant Ghanaians as there is limited research in these populations. The study was cross-sectional and quantitative in design. A majority of the study participants had experienced stress, discrimination and negative life events. Increased age, female sex, strong social support and high sense of mastery were associated with lower odds of experiencing psychosocial stressors in both populations. Interventions should be multi-level in design, focusing on the correlates which significantly influence the experience of psychosocial stressor

Microbes as Master Immunomodulators: Immunopathology, Cancer and Personalized Immunotherapies

The intricate interplay between the immune system and microbes is an essential part of the physiological homeostasis in health and disease. Immunological recognition of commensal microbes, such as bacterial species resident in the gut or lung as well as dormant viral species, i.e., cytomegalovirus (CMV) or Epstein-Barr virus (EBV), in combination with a balanced immune regulation, is central to achieve immune-protection. Emerging evidence suggests that immune responses primed to guard against commensal microbes may cause unexpected pathological outcomes, e.g., chronic inflammation and/or malignant transformation. Furthermore, translocation of immune cells from one anatomical compartment to another, i.e., the gut-lung axis via the lymphatics or blood has been identified as an important factor in perpetrating systemic inflammation, tissue destruction, as well as modulating host-protective immune responses. We present in this review immune response patterns to pathogenic as well as non-pathogenic microbes and how these immune-recognition profiles affect local immune responses or malignant transformation. We discuss personalized immunological therapies which, directly or indirectly, target host biological pathways modulated by antimicrobial immune responses

Antibody responses to <i>P. falciparum</i> blood stage antigens and incidence of clinical malaria in children living in endemic area in Burkina Faso

Abstract Background High parasite-specific antibody levels are generally associated with low susceptibility to Plasmodium falciparum malaria. This has been supported by several studies in which clinical malaria cases of P. falciparum malaria were reported to be associated with low antibody avidities. This study was conducted to evaluate the role of age, malaria transmission intensity and incidence of clinical malaria in the induction of protective humoral immune response against P. falciparum malaria in children living in Burkina Faso. Methods We combined levels of IgG and IgG subclasses responses to P. falciparum antigens: Merozoite Surface Protein 3 (MSP3), Merozoite Surface Protein 2a (MSP2a), Merozoite Surface Protein 2b (MSP2b), Glutamate Rich Protein R0 (GLURP R0) and Glutamate Rich Protein R2 (GLURP R2) in plasma samples from 325 children under five (05) years with age, malaria transmission season and malaria incidence. Results We notice higher prevalence of P. falciparum infection in low transmission season compared to high malaria transmission season. While, parasite density was lower in low transmission than high transmission season. IgG against all antigens investigated increased with age. High levels of IgG and IgG subclasses to all tested antigens except for GLURP R2 were associated with the intensity of malaria transmission. IgG to MSP3, MSP2b, GLURP R2 and GLURP R0 were associated with low incidence of malaria. All IgG subclasses were associated with low incidence of P. falciparum malaria, but these associations were stronger for cytophilic IgGs. Conclusions On the basis of the data presented in this study, we conclude that the induction of humoral immune response to tested malaria antigens is related to age, transmission season level and incidence of clinical malaria

Trained Immunity for Personalized Cancer Immunotherapy: Current Knowledge and Future Opportunities

Memory formation, guided by microbial ligands, has been reported for innate immune cells. Epigenetic imprinting plays an important role herein, involving histone modification after pathogen-/danger-associated molecular patterns (PAMPs/DAMPs) recognition by pattern recognition receptors (PRRs). Such “trained immunity” affects not only the nominal target pathogen, yet also non-related targets that may be encountered later in life. The concept of trained innate immunity warrants further exploration in cancer and how these insights can be implemented in immunotherapeutic approaches. In this review, we discuss our current understanding of innate immune memory and we reference new findings in this field, highlighting the observations of trained immunity in monocytic and natural killer cells. We also provide a brief overview of trained immunity in non-immune cells, such as stromal cells and fibroblasts. Finally, we present possible strategies based on trained innate immunity that may help to devise host-directed immunotherapies focusing on cancer, with possible extension to infectious diseases