Heterotrophic microbes are central to organic matter degradation and transformation in marine sediments. Currently, most investigations of benthic microbiomes do not differentiate between processes in the porewater and on the grains and, hence, only show a generalized picture of the community. This limits our understanding of the structure and functions of sediment microbiomes.
View Article and Find Full Text PDFOne of the most hostile marine habitats on Earth is the surface of the South Pacific Gyre (SPG), characterized by high solar radiation, extreme nutrient depletion, and low productivity. During the SO-245 "UltraPac" cruise through the center of the ultra-oligotrophic SPG, the marine alphaproteobacterial group AEGEAN169 was detected by fluorescence in situ hybridization at relative abundances up to 6% of the total microbial community in the uppermost water layer, with two distinct populations (Candidatus Nemonibacter and Ca. Indicimonas).
View Article and Find Full Text PDFPhages play an essential role in controlling bacterial populations. Those infecting Pelagibacterales (SAR11), the dominant bacteria in surface oceans, have been studied in silico and by cultivation attempts. However, little is known about the quantity of phage-infected cells in the environment.
View Article and Find Full Text PDFNet growth of microbial populations, that is, changes in abundances over time, can be studied using 16S rRNA fluorescence hybridization (FISH). However, this approach does not differentiate between mortality and cell division rates. We used FISH-based image cytometry in combination with dilution culture experiments to study net growth, cell division, and mortality rates of four bacterial taxa over two distinct phytoplankton blooms: the oligotrophs SAR11 and SAR86, and the copiotrophic phylum , and its genus .
View Article and Find Full Text PDFCurrent research posits that all multicellular organisms live in symbioses with associated microorganisms and form so-called metaorganisms or holobionts. Cnidarian metaorganisms are of specific interest given that stony corals provide the foundation of the globally threatened coral reef ecosystems. To gain first insight into viruses associated with the coral model system Aiptasia (), we analyzed an existing RNA-Seq dataset of aposymbiotic, partially populated, and fully symbiotic Aiptasia CC7 anemones with .
View Article and Find Full Text PDFBackground: Stony corals provide the structural foundation of coral reef ecosystems and are termed holobionts given they engage in symbioses, in particular with photosynthetic dinoflagellates of the genus Symbiodinium. Besides Symbiodinium, corals also engage with bacteria affecting metabolism, immunity, and resilience of the coral holobiont, but the role of associated viruses is largely unknown. In this regard, the increase of studies using RNA sequencing (RNA-Seq) to assess gene expression provides an opportunity to elucidate viral signatures encompassed within the data via careful delineation of sequence reads and their source of origin.
View Article and Find Full Text PDFTherapeutic options in severe emphysema are limited. Endoscopic lung volume reduction (ELVR) refers to bronchoscopically inducing volume loss to improve pulmonary mechanics and compliance, thereby reducing the work of breathing. Globally, this technique is increasingly used as treatment for advanced emphysema with the aim of obtaining similar functional advantages to surgical lung volume reduction, while reducing risks and costs.
View Article and Find Full Text PDFEmphysema is a very common cause of morbidity and mortality in South Africa (SA). Therapeutic options in severe emphysema are limited. Endoscopic lung volume reduction (ELVR) is increasingly being used internationally for the treatment of advanced emphysema in a subset of patients with advanced disease, aiming to obtain the same functional advantages as surgical lung volume reduction while reducing risks and costs.
View Article and Find Full Text PDFBackground: Xpert MTB/RIF has been shown to have a superior sensitivity to microscopy for acid fast bacilli (AFB) in sputum and has been recommended as a standard first line investigation for pulmonary tuberculosis (PTB). Bronchoscopy is a valuable tool in diagnosing PTB in sputum negative patients. There is limited data on the utility of Xpert MTB/RIF performed on bronchial lavage specimens.
View Article and Find Full Text PDFWe assessed the utility of ultrasound to guide the selection of closed pleural biopsy technique and site and to assess the respective contributions of repeat thoracentesis and closed pleural biopsy in 100 consecutive patients with undiagnosed pleural exudates. Thoracentesis was more likely to be diagnostic in TB than malignancy (77.8% vs 31.
View Article and Find Full Text PDFA 54-year-old man was referred with nonresolving pneumonia. He had been treated for community-acquired pneumonia 6 weeks earlier. He reported grade 2 dyspnea, malaise, and a nonproductive cough.
View Article and Find Full Text PDFMany countries are confronting climate change that threatens agricultural production and farmers' lives. Farmers' perceived risks of climate change and factors influencing those perceived risks are critical to their adaptive behavior and well-planned adaptation strategies. However, there is limited understanding of these issues.
View Article and Find Full Text PDFMinimally invasive treatment modalities for life-threatening haemoptysis in patients unresponsive to medical interventions and/or in patients deemed functionally inoperable are limited. We describe the implantation of endobronchial valves in a patient with recurrent haemoptysis, which presents both a novel indication for the use of these devices and a novel intervention for haemoptysis. Our patient is a 30-year-old male who developed bilateral upper lobe aspergillomata following previous pulmonary tuberculosis.
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