153 research outputs found
Functional and comparative analysis of expressed sequences from Diuraphis noxia infested wheat obtained utilizing the conserved Nucleotide Binding Site
Russian wheat aphid (Diuraphis noxia, Morvilko; RWA) is a major pest on wheat, barley and other triticale in South Africa. Infestation by the RWA results in altered protein expression patterns, which is manifested as differential expression of gene sequences. In the present study, Russian wheat aphid resistant (Tugela DN, Tugela*5/SA2199, Tugela*5/SA463, PI 137739, PI 262660, and PI 294994) and susceptible triticale (Tugela) were infested and cDNA synthesized. A PCR based approach was utilized to amplify the nucleotide binding site conserved region to obtain expressed sequence tags (ESTs) with homology to resistance gene analogs (RGAs). The approach proved highly feasible when the isolation of RGAs is the main objective, since 18% of all obtained ESTs showed significant hits with known RGAs, when translated into their corresponding amino acid sequences and searched against the nonredundant GenBank protein database using the BLASTX algorithm.
(African Journal of Biotechnology: 2003 2(4): 75-81
A fatal outcome of pica
A previously healthy 31 year old African male was assisting
friends with the repair of the roof of a neighboring house.
That evening at a social gathering the man complained of an
apparent headache and went home early where he later died
suddenly and unexpectedly. No history indicating the possibility
of an underlying psychiatric illness was obtained.
Due to the nature and circumstances surrounding the sudden
unexpected death the body was referred for a medico-legal
investigation in terms of the Inquests Act 58 of 1959.http://link.springer.com/journal/120242017-01-31hb2016Forensic Medicin
Genome Sequences of Three Vaccine Strains and Two Wild-Type Canine Distemper Virus Strains from a Recent Disease Outbreak in South Africa
Canine distemper virus causes global multihost infectious disease. This
report details complete genome sequences of three vaccine and two new wild-type
strains. The wild-type strains belong to the South African lineage, and all three vaccine
strains to the America 1 lineage. This constitutes the first genomic sequences of
this virus from South Africa.The National Zoological Gardens of South Africa and
funded by the National Research Foundation (NRF) Professional Development Program.http://genomea.asm.orgam2018Veterinary Tropical Disease
Immune Dysregulation Is Associated with Neurodevelopment and Neurocognitive Performance in HIV Pediatric Populations—A Scoping Review
HIV-1 is known for its complex interaction with the dysregulated immune system and is responsible for the development of neurocognitive deficits and neurodevelopmental delays in pediatric HIV populations. Considering that HIV-1-induced immune dysregulation and its association with neurodevelopmental and neurocognitive impairments in pediatric populations are not well understood, we conducted a scoping review on this topic. The study aimed to systematically review the association of blood and cerebrospinal fluid (CSF) immune markers with neurocognitive deficits and neurodevelopmental delays in pediatric HIV populations. PubMed, Scopus, and Web of Science databases were searched using a search protocol designed specifically for this study. Studies were selected based on a set eligibility criterion. Titles, abstracts, and full texts were assessed by two independent reviewers. Data from the selected studies were extracted and analyzed by two independent reviewers. Seven studies were considered eligible for use in this context, which included four cross-sectional and three longitudinal studies. An average of 130 (±70.61) children living with HIV, 138 (±65.37) children exposed to HIV but uninfected and 90 (±86.66) HIV-negative participants were included across the seven studies. Results indicate that blood and CSF immune markers are associated with neurocognitive development/performance in pediatric HIV populations. Only seven studies met the inclusion criteria, therefore, these limited the number of significant conclusions which could have been made by using such an approach. All considered, the evidence suggests that immune dysregulation, as in the case of adult HIV populations, also has a significant association with neurocognitive performance in pediatric HIV populations
Elucidating the Antimycobacterial Mechanism of Action of Decoquinate Derivative RMB041 Using Metabolomics
Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), still remains one of the leading causes of death from a single infectious agent worldwide. The high prevalence of this disease is mostly ascribed to the rapid development of drug resistance to the current anti-TB drugs, exacerbated by lack of patient adherence due to drug toxicity. The aforementioned highlights the urgent need for new anti-TB compounds with different antimycobacterial mechanisms of action to those currently being used. An N-alkyl quinolone; decoquinate derivative RMB041, has recently shown promising antimicrobial activity against Mtb, while also exhibiting low cytotoxicity and excellent pharmacokinetic characteristics. Its exact mechanism of action, however, is still unknown. Considering this, we used GCxGC-TOFMS and well described metabolomic approaches to analyze and compare the metabolic alterations of Mtb treated with decoquinate derivative RMB041 by comparison to non-treated Mtb controls. The most significantly altered pathways in Mtb treated with this drug include fatty acid metabolism, amino acid metabolism, glycerol metabolism, and the urea cycle. These changes support previous findings suggesting this drug acts primarily on the cell wall and secondarily on the DNA metabolism of Mtb. Additionally, we identified metabolic changes suggesting inhibition of protein synthesis and a state of dormancy
The altered human serum metabolome induced by a marathon
Introduction - Endurance races have been associated with a substantial amount of adverse effects which could lead to chronic disease and long-term performance impairment. However, little is known about the holistic metabolic changes occurring within the serum metabolome of athletes after the completion of a marathon.
Objectives - Considering this, the aim of this study was to better characterize the acute metabolic changes induced by a marathon.
Methods - Using an untargeted two dimensional gas chromatography time-of-flight mass spectrometry metabolomics approach, pre- and post-marathon serum samples of 31 athletes were analyzed and compared to identify those metabolites varying the most after the marathon perturbation.
Results - Principle component analysis of the comparative groups indicated natural differentiation due to variation in the total metabolite profiles. Elevated concentrations of carbohydrates, fatty acids, tricarboxylic acid cycle intermediates, ketones and reduced concentrations of amino acids indicated a metabolic shift between various fuel substrate systems. Additionally, elevated odd-chain fatty acids and α-hydroxy acids indicated the utilization of α-oxidation and autophagy as alternative energy-producing mechanisms. Adaptations in gut microbe-associated markers were also observed and correlated with the metabolic flexibility of the athlete.
Conclusion - From these results it is evident that a marathon places immense strain on the energy-producing pathways of the athlete, leading to extensive protein degradation, oxidative stress, mammalian target of rapamycin complex 1 inhibition and autophagy. A better understanding of this metabolic shift could provide new insights for optimizing athletic performance, developing more efficient nutrition regimens and identify strategies to improve recovery
Metabolomics of colistin methanesulfonate treated Mycobacterium tuberculosis
Over the past 5 years, there has been a renewed interest in finding new compounds with anti-TB action. Colistin methanesulfonate or polymyxin E, is a possible anti-TB drug candidate, which may in future be used either alone or in combination to the current 6 month “directly observed treatment short-course” (DOTS) regimen. However its mechanism of action has to date not yet been fully explored, and only described from a histological and genomics perspective. Considering this, we used a GCxGC-TOFMS metabolomics approach and identified those metabolite markers characterising Mycobacterium tuberculosis (Mtb) cultured in the presence of colistin methanesulfonate, in order to better understand or confirm its mechanism of action. The metabolite markers identified indicated a flux in the metabolism of the colistin methanesulfonate treated Mtb towards fatty acid synthesis and cell wall repair, confirming previous reports that colistin acts by disrupting the cell wall of mycobacteria. Accompanying this, is a subsequently elevated glucose uptake, since the latter now serves as the primary energy substrate for the upregulated glyoxylate cycle, and additionally as a precursor for further fatty acid synthesis via the glycerolipid metabolic pathway. Furthermore, the elevated concentrations of those metabolites associated with pentose phosphate, valine, threonine, and pentanediol metabolism, also confirms a shift towards glucose utilization for energy production, in the colistin methanesulfonate treated Mtb.Prof. Anton Stoltz and Prof. Ed Nardell are specifically thanked for their funding towards the cell cultures. The North West University is thanked for financial assistance of the research which forms part of a master's study.http://intl.elsevierhealth.com/journals/tube2019-07-01hj2018Internal Medicin
Association of Alcohol Consumption with Specific Biomarkers: A Cross-sectional Study in South Africa
Alcohol consumption plays an important role in the health transition
associated with urbanization in developing countries. Thus, reliable
tools for assessing alcohol intake levels are necessary. We compared
two biological markers of alcohol consumption and self-reported alcohol
intakes in participants from urban and rural South African communities.
This cross-sectional epidemiological survey was part of the North West
Province, South African leg of the 12-year International Prospective
Urban and Rural Epidemiology (PURE) study which investigates the health
transition in urban and rural subjects. A total of 2,010 apparently
healthy African volunteers (35 years and older) were recruited from a
sample of 6,000 randomly-selected households. Alcohol consumption was
assessed through self-reports (24-hour recalls and quantitative food
frequency questionnaire) and by two biological markers: percentage
carbohydrate-deficient transferrin (%CDT) and gamma-glutamyl
transferase (GGT). Of the 716 men and 1,192 women volunteers, 64% and
33% respectively reported regular alcohol consumption. Reported mean
habitual intakes of drinker men and women were 29.9 (\ub130.0) and
23.3 (\ub129.1) g of pure alcohol per day. Reported habitual intake
of the whole group correlated positively and significantly with both
%CDT (R=0.32; p 640.01) and GGT (R=0.43; p\u22640.01). The
correlation between the two biomarkers was low (0.211; p 640.01).
GGT and %CDT values should be interpreted with care in Africans as
self-reported non-drinker men and women had elevated levels of GGT (19%
and 26%) and %CDT (48% and 38%). A need exists for a more specific
biological marker for alcohol consumption in black Africans
Adjunct n-3 Long-Chain Polyunsaturated Fatty Acid Treatment in Tuberculosis Reduces Inflammation and Improves Anemia of Infection More in C3HeB/FeJ Mice With Low n-3 Fatty Acid Status Than Sufficient n-3 Fatty Acid Status
Populations at risk for tuberculosis (TB) may have a low n-3 polyunsaturated fatty acid
(PUFA) status. Our research previously showed that post-infection supplementation of
n-3 long-chain PUFA (LCPUFA) in TB without TB medication was beneficial in n-3
PUFA sufficient but not in low-status C3HeB/FeJ mice. In this study, we investigated
the effect of n-3 LCPUFA adjunct to TB medication in TB mice with a low compared
to a sufficient n-3 PUFA status. Mice were conditioned on an n-3 PUFA-deficient (n-
3FAD) or n-3 PUFA-sufficient (n-3FAS) diet for 6 weeks before TB infection. Postinfection
at 2 weeks, both groups were switched to an n-3 LCPUFA [eicosapentaenoic
acid (EPA)/docosahexaenoic acid (DHA)] supplemented diet and euthanized at 4- and
14- days post-treatment. Iron and anemia status, bacterial loads, lung pathology, lung
cytokines/chemokines, and lung lipid mediators were measured. Following 14 days of
treatment, hemoglobin (Hb) was higher in the n-3FAD than the untreated n-3FAS group
(p = 0.022), whereas the n-3FAS (drug) treated control and n-3FAS groups were not. Proinflammatory
lung cytokines; interleukin-6 (IL-6) (p = 0.011), IL-1a (p = 0.039), MCP1
(p = 0.003), MIP1- a (p = 0.043), and RANTES (p = 0.034); were lower, and the antiinflammatory
cytokine IL-4 (p=0.002) and growth factor GMCSF (p=0.007) were higher
in the n-3FAD compared with the n-3FAS mice after 14 days. These results suggest that
n-3 LCPUFA therapy in TB-infected mice, in combination with TB medication, may
improve anemia of infection more in low n-3 fatty acid status than sufficient status mice.
Furthermore, the low n-3 fatty acid status TB mice supplemented with n-3 LCPUFA
showed comparatively lower cytokine-mediated inflammation despite presenting with
lower pro-resolving lipid mediators
- …