Publications by authors named "Audrey Harris"

Microbes able to convert gaseous one-carbon (C1) waste feedstocks are increasingly important to transition to the sustainable production of renewable chemicals and fuels. Acetogens are interesting biocatalysts since gas fermentation using Clostridium autoethanogenum has been commercialised. However, most acetogen strains need complex nutrients, display slow growth, and are not robust for bioreactor fermentations.

View Article and Find Full Text PDF

Gas fermentation of CO and H is an attractive means to sustainably produce fuels and chemicals. Clostridium autoethanogenum is a model organism for industrial CO to ethanol and presents an opportunity for CO-to-ethanol processes. As we have previously characterized its CO/H chemostat growth, here we use adaptive laboratory evolution (ALE) with the aim of improving growth with CO/H.

View Article and Find Full Text PDF

Gas fermentation has emerged as a sustainable route to produce fuels and chemicals by recycling inexpensive one-carbon (C) feedstocks from gaseous and solid waste using gas-fermenting microbes. Currently, acetogens that utilise the Wood-Ljungdahl pathway to convert carbon oxides (CO and CO) into valuable products are the most advanced biocatalysts for gas fermentation. However, our understanding of the functionalities of the genes involved in the C-fixing gene cluster and its closely-linked genes is incomplete.

View Article and Find Full Text PDF

Transcriptome analysis via RNA sequencing (RNA-seq) has become a standard technique employed across various biological fields of study. The rapid adoption of the RNA-seq approach has been mediated, in part, by the development of different commercial RNA-seq library preparation kits compatible with standard next-generation sequencing (NGS) platforms. Generally, the essential steps of library preparation, such as rRNA depletion and first-strand cDNA synthesis, are tailored to a specific group of organisms (e.

View Article and Find Full Text PDF

Gas fermentation offers both fossil carbon-free sustainable production of fuels and chemicals and recycling of gaseous and solid waste using gas-fermenting microbes. Bioprocess development, systems-level analysis of biocatalyst metabolism, and engineering of cell factories are advancing the widespread deployment of the commercialised technology. Acetogens are particularly attractive biocatalysts but effects of the key physiological parameter-specific growth rate (μ)-on acetogen metabolism and the gas fermentation bioprocess have not been established yet.

View Article and Find Full Text PDF

In the developing spinal cord, Onecut transcription factors control the diversification of motor neurons into distinct neuronal subsets by ensuring the maintenance of Isl1 expression during differentiation. However, other genes downstream of the Onecut proteins and involved in motor neuron diversification have remained unidentified. In the present study, we generated conditional mutant embryos carrying specific inactivation of Onecut genes in the developing motor neurons, performed RNA-sequencing to identify factors downstream of Onecut proteins in this neuron population, and employed additional transgenic mouse models to assess the role of one specific Onecut-downstream target, the transcription factor Nkx6.

View Article and Find Full Text PDF

Spinal dorsal interneurons, which are generated during embryonic development, relay and process sensory inputs from the periphery to the central nervous system. Proper integration of these cells into neuronal circuitry depends on their correct positioning within the spinal parenchyma. Molecular cues that control neuronal migration have been extensively characterized but the genetic programs that regulate their production remain poorly investigated.

View Article and Find Full Text PDF

Acquisition of proper neuronal identity and position is critical for the formation of neural circuits. In the embryonic spinal cord, cardinal populations of interneurons diversify into specialized subsets and migrate to defined locations within the spinal parenchyma. However, the factors that control interneuron diversification and migration remain poorly characterized.

View Article and Find Full Text PDF

During embryonic development, the dorsal spinal cord generates numerous interneuron populations eventually involved in motor circuits or in sensory networks that integrate and transmit sensory inputs from the periphery. The molecular mechanisms that regulate the specification of these multiple dorsal neuronal populations have been extensively characterized. In contrast, the factors that contribute to their diversification into smaller specialized subsets and those that control the specific distribution of each population in the developing spinal cord remain unknown.

View Article and Find Full Text PDF

Spinal ventral interneurons regulate the activity of motor neurons, thereby controlling motor activities. Interneurons arise during embryonic development from distinct progenitor domains distributed orderly along the dorso-ventral axis of the neural tube. A single ventral progenitor population named p2 generates at least five V2 interneuron subsets.

View Article and Find Full Text PDF

The spinal cord contains neuronal circuits termed Central Pattern Generators (CPGs) that coordinate rhythmic motor activities. CPG circuits consist of motor neurons and multiple interneuron cell types, many of which are derived from four distinct cardinal classes of ventral interneurons, called V0, V1, V2 and V3. While significant progress has been made on elucidating the molecular and genetic mechanisms that control ventral interneuron differentiation, little is known about their distribution along the antero-posterior axis of the spinal cord and their diversification.

View Article and Find Full Text PDF

The human immunodeficiency virus (HIV), first identified in 1983 as the cause of acquired immunodeficiency syndrome (AIDS), has created a worldwide pandemic. This article is an overview of the HIV/AIDS syndrome, including the pathogenesis, pathophysiology, epidemiology, treatment options and prevention for HIV/AIDS.

View Article and Find Full Text PDF

Sudden onset of shortness of breath and chest pain as well as a decreased oxygen level in the blood can be signs that a patient is experiencing a pulmonary embolic episode; however, a great many other conditions also can cause these signs and symptoms. If left undiagnosed and untreated, pulmonary embolism can be potentially fatal. This article describes types of medical imaging used to evaluate possible pulmonary embolism, including conventional chest radiographs, spiral computed tomography, magnetic resonance imaging and nuclear medicine lung ventilation and perfusion imaging.

View Article and Find Full Text PDF

Bovine tuberculosis (bTB) is an important disease of cattle and an emerging infectious disease of humans. Cow- and badger-based control strategies have failed to eradicate bTB from the British cattle herd, and the incidence is rising by about 18%per year. The annual cost to taxpayers in Britain is currently 74 million UK pounds.

View Article and Find Full Text PDF

Classic symptoms of appendicitis include right lower quadrant pain on palpation, loss of appetite, nausea and vomiting. However, only about half of patients present with these characteristic symptoms. The remainder of patients must undergo some type of diagnostic study to verify or rule out appendicitis.

View Article and Find Full Text PDF