Publications by authors named "M NICOL"

Little is understood about the roles of mitochondria in pregnancy-related adaptations. Therefore, we evaluated associations of maternal early-to-mid pregnancy mitochondrial DNA copy number (mtDNAcn) and mtDNA methylation with birth size and gestational length. Michigan women ( = 396) provided venous bloodspots at median 11 weeks gestation to quantify mtDNAcn marker NADH-ubiquinone oxidoreductase chain 1 () using real-time quantitative PCR and mtDNA methylation at several regions within four mitochondria-specific genes using pyrosequencing: (mitochondrially encoded tRNA phenylalanine), (D-loop promoter region, heavy strand), (cytochrome b), and (D-loop promoter region, light strand).

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We derive a numerical model representing the emergence and evolution of SARS-CoV-2 variants, informed by data from in-vitro passaging experiments in Vero B4 cells. We compare our numerical simulation results against probabilistic derivations of the expected probability of and time until the fittest variant becomes fixed in the population. Contrary to literature surrounding DNA viruses and eukaryotes where probabilities of fitness extremes are often modelled by exponential decaying tail, we show that above wildtype fitness differences for SARS-CoV-2 are actually best modelled by a heavy-tailed Fréchet distribution.

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Article Synopsis
  • Children have shown strong immune responses to SARS-CoV-2 during various pandemic waves, with a significant increase in seropositivity from 34.2% after the first wave to 99.2% after the fifth wave, despite experiencing minimal severe illness.
  • The study found that IgG antibodies developed through natural exposure were effective in protecting children from future infections, with varying levels of effectiveness against different variants, showing the highest protection against the Beta variant and the least against Omicron.
  • Maternal seropositivity was linked to higher child seropositivity, indicating that the immune status of mothers plays a crucial role in the immune response of their children against COVID-19.
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Background: Paediatric tuberculosis leads to more than 200 000 deaths annually. We aimed to investigate the incidence of Mycobacterium tuberculosis infection and tuberculosis disease in the first decade of life in the Drakenstein Child Health Study (DCHS), a South African cohort in a community with high tuberculosis and HIV incidence.

Methods: In this prospective birth cohort study, we enrolled pregnant women aged 18 years or older who were between 20 and 28 weeks' of gestation in a peri-urban setting outside of Cape Town, South Africa.

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complex is a cause of serious lung infections in people with cystic fibrosis, exhibiting extremely high levels of antimicrobial resistance. These infections are difficult to treat and are associated with high morbidity and mortality. With a notable lack of new antibiotic classes currently in development, exploring alternative antimicrobial strategies for complex is crucial.

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