Medicinal Marijuana: A Promising Potential Treatment for Obstructive Sleep Apnea

Obstructive Sleep Apnea (OSA) is a common sleep disorder in mammals which is characterized by the repeated collapse of the upper airway. It is a known cause of hypertension, cardiovascular disease, and, in some cases, death. OSA is commonly treated by medical devices and surgeries. Although effective, these treatments are associated with unwanted side-effects and further complications. In recent years, the role of medicinal marijuana has grown as a potential treatment for sleep disorders. Further research must be conducted to determine the efficacy and safety of cannabis as a treatment for OSA.

Increasing the brightness of red fluorescent proteins by saturation mutagenesis

Red fluorescent proteins (RFPs) are genetically-encoded fluorophores that are widely used for in vivo imaging. For all applications of RFPs, brighter variants are desired. Previously, we improved the brightness of mRojoA, a red-shifted mutant of the widely-used RFP mCherry, by designing a triple-decker motif of aromatic rings around its chromophore. This yielded the brighter variant mRojo-VHSV, which contains a triple-decker motif consisting of His and Tyr side chains that pack against the chromophore. This improved chromophore packing resulted in an approximately 3-fold brightness increase at physiological pH. However, the His side chain in the triple-decker motif of mRojo-VHSV adopted a perpendicular arrangement to the other two, which may result in a suboptimal packing arrangement. To further improve chromophore packing in mRojo-VHSV, we performed saturation mutagenesis of residues surrounding its triple-decker motif (positions 62, 97, 165, and 199). Using a microplate fluorescence screening assay, a total of 376 colonies were screened for improved brightness. The brightest mutant found, L199M, was expressed and purified, and its spectral properties were characterized in detail. We found that the quantum yield of this variant was improved by two-fold, resulting in a two-fold brightness increase compared to mRojo-VHSV as well as a 5.3-fold increase in brightness compared to mRojoA. The L199M improved variant is the basis for continued engineering with the goal of further improving the spectral properties of this family of RFPs.

Examining cognitive training and executive function in older adults

Studies have shown that cognitive functions decline with increasing age. As the population of older adults (OA) has grown, interest in cognitive training programs (CTP) has steadily expanded. The present study investigated whether CTP can lead to improvements in the performance of OA on cognitive tasks. Thirty-five adults (OA; 60-87 years) were recruited to complete 25 sessions of a CTP over five weeks, with assessments completed before and after the program. Thirty-two young adults (YA; 17-27 years) were also recruited to complete one assessment for baseline comparison with OA. During assessments, participants were evaluated using tasks of executive function, including the N-back task of working memory and Flanker task of inhibition. The response time (RT) and hit rates of YA and OA on these tasks were examined at baseline, as well as changes in OA pre- and post-training. Repeated measures analysis of variance indicated a reduction of pre- and post-training RT for the Flanker task. There was no post-training change in RT on the N-back task. While OA hit rates did not change significantly pre- and post-assessment on the Flanker task, they showed increased hit rates post-training in the N-back task. In both tasks, OA and YA hit rates and RT were significantly different, with YA demonstrating lower RT and hit rate compared to OA. Follow-up studies will determine whether other factors can also lead to improvement. Determining whether CTP can improve cognitive performance in OA can help determine the potential of such approaches to prevent or rehabilitate age-related cognitive decline.

Shocking the brain to regain motor function : a non-invasive therapy for stroke patients

Invasive treatments and its associated risks are important factors of concern when the conditions are affecting the nervous system. Transcranial direct current stimulation (tDCS) is a non-invasive technique that stimulates brain areas through the scalp and has excitatory or inhibitory neuromodulatory effects. In the context of stroke patients, recovery is often impaired from the increased inhibition of the damaged area from the unaffected hemisphere. Fujimoto et al. uses dual-hemisphere transcranial direct current stimulation to address this interhemispheric inhibition and demonstrates that stroke patients were able to periodically restore sensory deficits.

Chromosomal instability and aneuploidy: a conundrum in cancer evolution

Chromosomal instability (CIN), defined as an increased rate of gain or loss of whole chromosomes, leads to aneuploid cells, which are cells that display an abnormal number of chromosomes. Both CIN and aneuploidy are hallmarks of cancer, yet the underlying mechanisms of CIN and aneuploidy and their impact on tumourigenesis have remained poorly defined. Although multiple mechanisms have been proposed to explain the role of CIN and aneuploidy in tumourigenesis, this review focuses on three principal pathways leading to CIN: spindle assembly checkpoint defects, merotelic attachments, and cohesion defects. Here, we provide a brief overview of the current understanding of the roles of these mechanisms in CIN and aneuploidy. We also present emerging evidence that contradicts the importance of certain mechanisms in cancer evolution. A clearer understanding of these fundamental pathways could prove to be helpful in developing effective cancer therapies.

Taking the hydro out of hydrofracturing: Application of ultra-light weight proppants to cryogenic liquid nitrogen as a fracturing fluid

In the last decade, hydraulic fracturing has rapidly gained popularity worldwide, emerging as the leading method of natural gas extraction in the United States. However, the practice remains controversial due to its contribution to greenhouse gas emissions and the contamination of freshwater used in fracturing fluids. Although waterless fracturing fluids have been developed, including those using N2, CO2, oil, and alcohol, their application has been limited largely due to reduced fracturing power. Recent research has demonstrated that cryogenic nitrogen may prove a viable alternative, if this issue is properly addressed. Addition of durable, lightweight proppants is one way to increase fracturing power. This study aims to investigate the effect of proppant addition on the fracturing capabilities of cryogenic nitrogen. Three ultra-lightweight proppants will be combined with liquid nitrogen and fracturing power will be measured using triaxial stress tests. This novel approach has not yet been explored and will open more avenues of research into sustainable and efficient fracturing using cryogenic nitrogen.

Comparison of regenerative neurogenesis in response to CNS injury between adult zebrafish and mice

The difference between adult zebrafish and mice in their regenerative capacity following central nervous system (CNS) injury is influenced by the permissiveness of the brain microenvironment aside from the intrinsic neurogenic potential of the cell population. In adult zebrafish, glia cells largely retain their radial characteristics and neurogenic capacity, and the zebrafish brain shows full recovery after traumatic brain injury (TBI) as well as spinal cord injury (SCI). Conversely, in mice, radial glia (RG) have largely differentiated into astrocytes. Excluding certain brain regions, following TBI, reactive astrocytes that show the potential to become neural stem cells (NSCs) in vitro remain strictly non-neurogenic in vivo due to the presence of inhibitory factors in the microenvironment. Combined with prolonged inflammation and gliosis, injury to the CNS eventually results in formation of a glial scar further impeding regeneration. However in rodents, suppression of neurogenesis may be a protection mechanism against possible detrimental side-effects of neurogenesis in the long term.

The effect of context on sensory accumulation involved in decision-making

The underlying processes allowing for decision-making has been a question of interest for many neuroscientists. The lateral intraparietal cortex, or LIP, was shown to accumulate context and sensory information to compute a decision variable. The following review will present the work of Kumano, Suda and Uka who studied the link between context and sensory information during decision-making. To do so, a monkey was trained to associate the color of a fixating dot to one of two tasks. The tasks consisted in either indicating the motion or the depth of themajority of the dots on a screen. The local field potential of the LIP neurons was recorded, and the researchers found a role of context during the stimulus presentation in regards to decision formation. The results have important implication for mental disorders involving malfunction in decision processes.

Reducing volatile organic compound emissions with a biofilter inoculated with synthetically engineered Escherichia coli

Various byproducts of fracking, such as methane gas, benzene, and other Volatile Organic Compounds (VOCs), have become a target for studies on health and environmental damage. These compounds are released during natural gas and petroleum extraction, and from the toxic residual water created from the fracking process. Although the long-term effects of some of these chemicals have yet to be determined, the elevated levels present in neighboring communities have been shown to cause an increase in the prevalence of acute respiratory, neurological, and reproductive diseases. In order to reduce the levels of these harmful airborne pollutants, we propose the creation of a biofilter inoculated with genetically engineered bacteria designed to metabolize VOCs and convert them into safer end products.

Expressing the randomity of events – An analysis of random number generation with given distributions

In cases where it is necessary to generate random numbers that obey specific distributions, some of those distributions can be expressed as mathematical functions while others cannot. This is especially the case for epidemiological, medical, and pharmaceutical investigations, where more accurate methods, utilising actual distribution (from survey and experimental data) to generate random numbers may be required. In this study, three methods are analyzed to demonstrate simple computation examples. These methods include: inverse transform,acceptance-rejection, and Monte-Carlo simulations. Their applications are explored from a data analysis point of view. Additionally, this article discusses a flexible and practical approach of statistical measures optimization, which approximates the solution by fitting the statistical measures.