Effect of Carbohydrates on the Gut Microbiome

The microbiome within the gut is directly linked to biological processes within a person, influencing factors such as metabolism, signaling pathways, and available nutrients. Long term dieting is known to alter ecological conditions within the gut, allowing certain types of microbes to flourish. Therefore, the overall health of an individual is ultimately influenced by shifts in the microbial community state caused by persistent dieting. This study investigates the connection between diet and the microbiome and draws an understanding of how common carbohydrates in food can affect bacterial composition. Using KBase software, anaerobic bacterial growth was investigated for bacteria subject to a defined media with distinct sugars. Common bacteria found in young children were studied as microbiome development begins post-partum. The results show that only certain carbohydrates have a crucial impact on bacterial growth while others are inert. In future studies, it is recommended that co-cultures of bacteria are studied in the sugar additive media to determine relative abundance and how different bacterial strains can dominate one another

The bovine nasal fungal community and associations with bovine respiratory disease

IntroductionEffective identification and treatment of bovine respiratory disease (BRD) is an ongoing health and economic issue for the dairy and beef cattle industries. Bacteria pathogens Pasteurellamultocida, Mycoplasmabovis, Mannheimia haemolytica, and Histophilus somni and the virus Bovine herpesvirus-1 (BHV-1), Bovine parainfluenza-3 virus (BPIV-3), Bovine respiratory syncytial virus (BRSV), Bovine adenovirus 3 (BAdV3), bovine coronavirus (BoCV) and Bovine viral diarrhea virus (BVDV) have commonly been identified in BRD cattle; however, no studies have investigated the fungal community and how it may also relate to BRD.MethodsThe objective of this study was to understand if the nasal mycobiome differs between a BRD-affected (n = 56) and visually healthy (n = 73) Holstein steers. Fungal nasal community was determined by using Internal Transcribed Spacer (ITS) sequencing.ResultsThe phyla, Ascomycota and Basidiomycota, and the genera, Trichosporon and Issatchenkia, were the most abundant among all animals, regardless of health status. We identified differences between healthy and BRD animals in abundance of Trichosporon and Issatchenkia orientalis at a sub-species level that could be a potential indicator of BRD. No differences were observed in the nasal fungal alpha and beta diversity between BRD and healthy animals. However, the fungal community structure was affected based on season, specifically when comparing samples collected in the summer to the winter season. We then performed a random forest model, based on the fungal community and abundance of the BRD-pathobionts (qPCR data generated from a previous study using the same animals), to classify healthy and BRD animals and determine the agreement with visual diagnosis. Classification of BRD or healthy animals using ITS sequencing was low and agreed with the visual diagnosis with an accuracy of 51.9%. A portion of the ITS-predicted BRD animals were not predicted based on the abundance of BRD pathobionts. Lastly, fungal and bacterial co-occurrence were more common in BRD animals than healthy animals.DiscussionThe results from this novel study provide a baseline understanding of the fungal diversity and composition in the nasal cavity of BRD and healthy animals, upon which future interaction studies, including other nasal microbiome members to further understand and accurately diagnose BRD, can be designed

Branching and size of CTAB-coated gold nanostars control the colorimetric detection of bacteria

Rapid detection of pathogenic bacteria is challenging because conventional methods require long incubation times. Nanoparticles have the potential to detect pathogens before they can cause an infection. Gold nanostars have recently been used for colorimetric biosensors but they typically require surface modification with antibodies or aptamers for cellular detection. Here, CTAB-coated gold nanostars have been used to rapidly (<5 min) detect infective doses of a model Gram-positive pathogen Staphylococcus aureus by an instrument-free colorimetric method. Varying the amounts of gold nanoseed precursor and surfactant can tune the size and degree of branching of gold nanostars as studied here by transmission electron microscopy. The size and morphology of gold nanostars determine the degree and rate of color change in the presence of S. aureus. The optimal formulation achieved maximum color contrast in the presence of S. aureus and produced a selective response in comparison to polystyrene microparticles and liposomes. These gold nanostars were characterized using UV-Visible spectroscopy to monitor changes in their surface plasmon resonance peaks. The visual color change was also quantified over time by measuring the RGB components of the pixels in the digital images of gold nanostar solutions. CTAB-coated gold nanostars serve as a promising material for simple and rapid detection of pathogens.This work was financially supported by the Natural Sciences and Engineering Research Council of Canada (NSERC)and 20/20 NSERC Ophthalmic Materials Network.M. S. Verma is grateful for the NSERC Vanier Canada Graduate Scholarship.P. Z. Chen is thankful for the NSERC Undergraduate Student Research Award

Controlling “chemical nose” biosensor characteristics by modulating gold nanoparticle shape and concentration

Verma, M. S., Chen, P. Z., Jones, L., & Gu, F. X. (2015). Controlling “chemical nose” biosensor characteristics by modulating gold nanoparticle shape and concentration. Sensing and Bio-Sensing Research, 5, 13–18. https://doi.org/10.1016/j.sbsr.2015.04.007Conventional lock-and-key biosensors often only detect a single pathogen because they incorporate biomolecules with high specificity. “Chemical nose” biosensors are overcoming this limitation and identifying multiple pathogens simultaneously by obtaining a unique set of responses for each pathogen of interest, but the number of pathogens that can be distinguished is limited by the number of responses obtained. Herein, we use a gold nanoparticle-based “chemical nose” to show that changing the shapes of nanoparticles can increase the number of responses available for analysis and expand the types of bacteria that can be identified. Using four shapes of nanoparticles (nanospheres, nanostars, nanocubes, and nanorods), we demonstrate that each shape provides a unique set of responses in the presence of different bacteria, which can be exploited for enhanced specificity of the biosensor. Additionally, the concentration of nanoparticles controls the detection limit of the biosensor, where a lower concentration provides better detection limit. Thus, here we lay a foundation for designing “chemical nose” biosensors and controlling their characteristics using gold nanoparticle morphology and concentration

Interactions Between Humans and Dogs During the COVID-19 Pandemic: Recent Updates and Future Perspectives

COVID-19 is one of the deadliest epidemics. This pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but the role of dogs in spreading the disease in human society is poorly understood. This review sheds light on the limited susceptibility of dogs to COVID-19 infections which is likely attributed to the relatively low levels of angiotensin-converting enzyme 2 (ACE2) in the respiratory tract and the phylogenetic distance of ACE2 in dogs from the human ACE2 receptor. The low levels of ACE2 affect the binding affinity between spike and ACE2 proteins resulting in it being uncommon for dogs to spread the disease. To demonstrate the role of dogs in spreading COVID-19, we reviewed the epidemiological studies and prevalence of SARS-CoV-2 in dogs. Additionally, we discussed the use of detection dogs as a rapid and reliable method for effectively discriminating between SARS-CoV-2 infected and non-infected individuals using different types of samples (secretions, saliva, and sweat). We considered the available information on COVID-19 in the human–dog interfaces involving the possibility of transmission of COVID-19 to dogs by infected individuals and vice versa, the human–dog behavior changes, and the importance of preventive measures because the risk of transmission by domestic dogs remains a concern

Soft, Rotating Pneumatic Actuator

This paper describes a soft pneumatic actuator that generates cyclical motion. The actuator consists of several (three, four, or five) chambers (arranged around the circumference of a circle surrounding a central rod) that can be actuated independently using negative pressure (or partial vacuum). Sequential actuation of the four-chamber device using reduced pressure moves the central rod cyclically in an approximately square path. We characterize the trajectory of the actuator and the force exerted by it, as we vary the material used for fabrication, the number of chambers, and the size of the actuator. We demonstrate two applications of this actuator: to deliver fluid while stirring (by replacing the central rod with a needle), and for locomotion that mimics a reptilian gait (by combining four actuators together).Chemistry and Chemical Biolog

Cost-effective Paper-based Diagnostic Using Split Proteins to Detect Yeast Infections

The common yeast infection, vulvovaginal candidiasis, affects three out of four women throughout their lifetime and can be spread to their child in the form of oral candidiasis (thrush). This disease is caused by the fungal pathogen Candida albicans, which is also a major cause of systemic candidiasis, a rarer but deadly disease with up to a 49% lethality rate. Current widely-used diagnostic methods include cell cultures, pH tests, and antibody detection, to assist effective treatment. Despite availability of various diagnostic methods, there is no inexpensive, rapid, and accurate way to detect C. albicans infection. This project aims to develop a paper-based diagnostic test for C. albicans that is, cost-effective, quick, and precise. The test detects the specific biomarkers farnesol and tyrosol produced by C. albicans by binding them to the split proteins pqsR and tyrosinase, respectively. Upon binding, a split horseradish peroxidase catalyzes and produces an amplified colorimetric signal by oxidizing the substrate tetramethylbenzidine (TMB) turning the paper blue. This test will produce a colorimetric output for a simple-to-understand diagnosis without any infrastructure. We predict that this device can give a response in under 2 minutes while costing around an estimated 10 cents per device This test may provide a way for an easy and cheap way to diagnose candidiasis worldwide, reducing the abuse of antifungals and provide an accurate way to treat vulvovaginal candidiasis and systemic candidiasis

Cost-effective Paper-based Diagnostic Using Split Proteins to Detect Yeast Infections

The common yeast infection, vulvovaginal candidiasis, affects three out of four women throughout their lifetime and can be spread to their child in the form of oral candidiasis (thrush). This disease is caused by the fungal pathogen Candida albicans, which is also a major cause of systemic candidiasis, a rarer but deadly disease with up to a 49% lethality rate. Current widely-used diagnostic methods include cell cultures, pH tests, and antibody detection, to assist effective treatment. Despite availability of various diagnostic methods, there is no inexpensive, rapid, and accurate way to detect C. albicans infection. This project aims to develop a paper-based diagnostic test for C. albicans that is, cost-effective, quick, and precise. The test detects the specific biomarkers farnesol and tyrosol produced by C. albicans by binding them to the split proteins pqsR and tyrosinase, respectively. Upon binding, a split horseradish peroxidase catalyzes and produces an amplified colorimetric signal by oxidizing the substrate tetramethylbenzidine (TMB) turning the paper blue. This test will produce a colorimetric output for a simple-to-understand diagnosis without any infrastructure. We predict that this device can give a response in under 2 minutes while costing around an estimated 10 cents per device This test may provide a way for an easy and cheap way to diagnose candidiasis worldwide, reducing the abuse of antifungals and provide an accurate way to treat vulvovaginal candidiasis and systemic candidiasis

Chronic Obstructive Pulmonary Disease and Lung Cancer: Underlying Pathophysiology and New Therapeutic Modalities

Chronic obstructive pulmonary disease (COPD) and lung cancer are major lung diseases affecting millions worldwide. Both diseases have links to cigarette smoking and exert a considerable societal burden. People suffering from COPD are at higher risk of developing lung cancer than those without, and are more susceptible to poor outcomes after diagnosis and treatment. Lung cancer and COPD are closely associated, possibly sharing common traits such as an underlying genetic predisposition, epithelial and endothelial cell plasticity, dysfunctional inflammatory mechanisms including the deposition of excessive extracellular matrix, angiogenesis, susceptibility to DNA damage and cellular mutagenesis. In fact, COPD could be the driving factor for lung cancer, providing a conducive environment that propagates its evolution. In the early stages of smoking, body defences provide a combative immune/oxidative response and DNA repair mechanisms are likely to subdue these changes to a certain extent; however, in patients with COPD with lung cancer the consequences could be devastating, potentially contributing to slower postoperative recovery after lung resection and increased resistance to radiotherapy and chemotherapy. Vital to the development of new-targeted therapies is an in-depth understanding of various molecular mechanisms that are associated with both pathologies. In this comprehensive review, we provide a detailed overview of possible underlying factors that link COPD and lung cancer, and current therapeutic advances from both human and preclinical animal models that can effectively mitigate this unholy relationship