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Multispectral Imaging for Microchip Electrophoresis Enables Point-of-Care Newborn Hemoglobin Variant Screening
Get PDFHemoglobin (Hb) disorders affect nearly 7% of the world\u27s population. Globally, around 400,000 babies are born annually with sickle cell disease (SCD), primarily in sub-Saharan Africa where morbidity and mortality rates are high. Screening, early diagnosis, and monitoring are not widely accessible due to technical challenges and cost. We hypothesized that multispectral imaging will allow sensitive hemoglobin variant identification in existing affordable paper-based Hb electrophoresis. To test this hypothesis, we developed the first integrated point-of-care multispectral Hb variant test: Gazelle-Multispectral. Here, we evaluated the accuracy of Gazelle-Multispectral for Hb variant newborn screening in 265 newborns with known hemoglobin variants including hemoglobin A (Hb A), hemoglobin F (Hb F), hemoglobin S (Hb S) and hemoglobin C (Hb C). Gazelle-Multispectral detected levels of Hb A, Hb F, Hb S, and Hb C/E/A2, demonstrated high correlations with the results reported by laboratory gold standard high performance liquid chromatography (HPLC) at Pearson Correlation Coefficient = 0.97, 0.97, 0.93, and 0.95. Gazelle-Multispectral demonstrated accuracy of 96.8% in subjects of 0–3 days, and 96.9% in newborns. The ability to obtain accurate results on newborn samples suggest that Gazelle-Multispectral can be suitable for large-scale newborn screening and for diagnosis of SCD in low resource settings
Cognitive Functioning and Prevalence of Seizures Among Older Persons in Uganda: A Hospital-Based, Cross-Sectional Study
No full textThere is limited data on the prevalence of seizures and dementia among older persons in Uganda. We evaluated cognitive functioning, and the prevalence and factors associated with seizures among older persons attending an outpatient medical clinic in Uganda. We randomly selected older adults (60 years and above) attending Kiruddu National Referral Hospital medical outpatient clinics between October 2020 and March 2021. We excluded individuals with a history of head injury, brain tumors, mental retardation, co-morbidity with HIV and patients who have had recent brain surgery. Cognitive functioning was assessed using the Identification for Dementia in Elderly Africans (IDEA) tool. We enrolled 407 participants, with a median (inter-quartile range) age of 67 (64-73) years. Majority were female (n = 292, 71.7%). The prevalence of seizure was 1.5% (95% confidence interval [CI]: 0.7-3.3). All 6 participants reported generalized tonic-clonic seizure type. Self-reported seizure was associated with being female (adjusted prevalence ratio [aPR]: 0.79, 95%CI: 0. 67-0.93, P =.02) and residing in Mukono district (aPR: 17.26, 95%CI: 1.64-181.55, P =.018). Overall, 114 (28.1%) participants had cognitive deficit; 9 (2.2%) dementia and 105 (25.9%) impaired cognition. Cognitive deficit was independently associated with female gender (aPR: 0.61, 95%CI: 0.44-0.85, P =.003), formal employment (aPR: 0.53, 95%CI: 0.35-0.81, P =.003), age 70-74 (aPR: 1.69, 95%CI: 1.00-2.86, P =.049), and ≥ 75 years (aPR: 2.81, 95%CI: 1.71-4.61, P =.001). Prevalence of seizures among participants with cognitive deficit was 5.3% (6/114). Among older persons attending a medical clinic in Uganda, almost one-third had cognitive deficit with seizure prevalence being higher among these individuals
Biomechanical and Sensory Feedback Regularize the Behavior of Different Locomotor Central Pattern Generators
No full textThis work presents an in-depth numerical investigation into a hypothesized two-layer central pattern generator (CPG) that controls mammalian walking and how different parameter choices might affect the stepping of a simulated neuromechanical model. Particular attention is paid to the functional role of features that have not received a great deal of attention in previous work: the weak cross-excitatory connectivity within the rhythm generator and the synapse strength between the two layers. Sensitivity evaluations of deafferented CPG models and the combined neuromechanical model are performed. Locomotion frequency is increased in two different ways for both models to investigate whether the model’s stability can be predicted by trends in the CPG’s phase response curves (PRCs). Our results show that the weak cross-excitatory connection can make the CPG more sensitive to perturbations and that increasing the synaptic strength between the two layers results in a trade-off between forced phase locking and the amount of phase delay that can exist between the two layers. Additionally, although the models exhibit these differences in behavior when disconnected from the biomechanical model, these differences seem to disappear with the full neuromechanical model and result in similar behavior despite a variety of parameter combinations. This indicates that the neural variables do not have to be fixed precisely for stable walking; the biomechanical entrainment and sensory feedback may cancel out the strengths of excitatory connectivity in the neural circuit and play a critical role in shaping locomotor behavior. Our results support the importance of including biomechanical models in the development of computational neuroscience models that control mammalian locomotion
On the Photostability of Cyanuric Acid and Its Candidature as a Prebiotic Nucleobase
Get PDFCyanuric acid is a triazine derivative that has been identified from reactions performed under prebiotic conditions and has been proposed as a prospective precursor of ancestral RNA. For cyanuric acid to have played a key role during the prebiotic era, it would have needed to survive the harsh electromagnetic radiation conditions reaching the Earth’s surface during prebiotic times (≥200 nm). Therefore, the photostability of cyanuric acid would have been crucial for its accumulation during the prebiotic era. To evaluate the putative photostability of cyanuric acid in water, in this contribution, we employed density functional theory (DFT) and its time-dependent variant (TD-DFT) including implicit and explicit solvent effects. The calculations predict that cyanuric acid has an absorption maximum at ca. 160 nm (7.73 eV), with the lowest-energy absorption band extending to ca. 200 nm in an aqueous solution and exhibiting negligible absorption at longer wavelengths. Excitation of cyanuric acid at 160 nm or longer wavelengths leads to the population of S5,6 singlet states, which have ππ* character and large oscillator strengths (0.8). The population reaching the S5,6 states is expected to internally convert to the S1,2 states in an ultrafast time scale. The S1,2 states, which have nπ* character, are predicted to access a conical intersection with the ground state in a nearly barrierless fashion (ca. ≤ 0.13 eV), thus efficiently returning the population to the ground state. Furthermore, based on calculated spin–orbit coupling elements of ca. 6 to 8 cm−1, the calculations predict that intersystem crossing to the triplet manifold should play a minor role in the electronic relaxation of cyanuric acid. We have also calculated the vertical ionization energy of cyanuric acid at 8.2 eV, which predicts that direct one-photon ionization of cyanuric acid should occur at ca. 150 nm. Collectively, the quantum-chemical calculations predict that cyanuric acid would have been highly photostable under the solar radiation conditions reaching the Earth’s surface during the prebiotic era in an aqueous solution. Of relevance to the chemical origin of life and RNA-first theories, these observations lend support to the idea that cyanuric acid could have accumulated in large quantities during the prebiotic era and thus strengthens its candidature as a relevant prebiotic nucleobase
Antibiotic Exposure and Acquisition of Antibiotic-Resistant Gram-Negative Bacteria among Outpatients at a US Veterans Affairs Medical Center
Get PDFObjectives: To assess the prevalence of antibiotic-resistant gram-negative bacteria (R-GNB) among patients without recent hospitalization and to examine the influence of outpatient antibiotic exposure on the risk of acquiring R-GNB in this population. Design: 2-year retrospective cohort study. Setting: Regional Veterans Affairs healthcare system. Patients: Outpatients at 13 community-based clinics. Methods: We examined the rate of acquisition of R-GNB within 90 days following an outpatient visit from 2018 to 2019. We used clinical and administrative databases to determine and summarize prescriptions for systemic antibiotics, associated infectious diagnoses, and subsequent R-GNB acquisition among patients without recent hospitalizations. We also calculated the odds ratio of R-GNB acquisition following antibiotic exposure. Results: During the 2-year study period, 7,215 patients had outpatient visits with microbiological cultures obtained within 90 days. Of these patients, 206 (2.9%) acquired an R-GNB. Among patients receiving antibiotics at the visit, 4.6% acquired a R-GNB compared to 2.7% among patients who did not receive antibiotics, yielding an unadjusted odds ratio of 1.75 (95% confidence interval, 1.18-2.52) for a R-GNB following an outpatient visit with versus without an antibiotic exposure. Regardless of R-GNB occurrence, \u3e50% of antibiotic prescriptions were issued at visits without an infectious disease diagnosis or issued without documentation of an in-person or telehealth clinical encounter. Conclusions: Although the rate of R-GNBs was low (2.9%), the 1.75-fold increased odds of acquiring a R-GNB following an outpatient antibiotic highlights the importance of antimicrobial stewardship efforts in outpatient settings. Specific opportunities include reducing antibiotics prescribed without an infectious diagnosis or a clinical visit
An Assessment of Requirements in Investments, New Technologies, and Infrastructures to Achieve the SDGs
Get PDFBackground: The implementation of the Sustainable Development Goals (SDGs) requires much planning and the provision of resources, especially regarding the necessary investments, technologies and infrastructures needed. Yet, it is presently unclear how available these elements are, what gaps exist, what changes have taken place in terms of their availability since the adoption of the SDGs and what their requirements will be in the future. The knowledge gap has become even more concerning because of the impact of the COVID-19 pandemic. Using a bibliometric analysis, an assessment of the global progress of SDG implementation and requirements, identifying challenges through the development of a matrix, and a set of 11 case studies to triangulate the holistic analysis, an assessment of the global progress of the SDGs implementation and the impact of the COVID-19 pandemic on this process was carried out. Results: The findings suggest that the scope and width of resources limitation are currently undermining the implementation of the SDGs. Apart from the fact that the pace of progress has been insufficient, the potential of the SDGs in pursuing sustainability and improving life quality is not fully realised. This trend suggests that a substantial acceleration of the efforts is needed, especially for the five SDGs whose progress since 2015 has not been optimal, namely SDG2, SDG11, SDG13, SDG15, and SDG16, while SDG3, SDG7, SDG9, SDG14, and SDG17 show signs of progress. The case studies showed that different industries have dissimilar effects on achieving the SDGs, with the food sector correlating with 15 SDGs, as opposed to the energy sector correlating with 6 SDGs. Accordingly, the priority level assessment in terms of achieving the SDGs, points to the need to further advance the above-mentioned five SDGs, i.e., 2, 11, 13, 15 and 16. Conclusions: This study fills in a knowledge gap in respect of the current need for and availability of investments, new technologies, and infrastructures to allow countries to pursue the SDGs. It is suggested that this availability is rather limited in specific contexts. In respect of the needs to be addressed, these include resource-related constraints, limited technologies and infrastructures, affecting SDG2, SDG11, SDG13, SDG15, and SDG16, whose progress needs to be enhanced. Since the global progress in the process of implementation of the SDGs depends directly and indirectly on addressing the resource gaps, it is suggested that this topic be further investigated, so that the present imbalances in the three dimensions of sustainable development: the economic, social and environmental, be adequately addressed
Atomically Dispersed Janus Nickel Sites on Red Phosphorus for Photocatalytic Overall Water Splitting
No full textSingle-atom nickel catalysts hold great promise for photocatalytic water splitting due to their plentiful active sites and cost-effectiveness. Herein, we adopt a reactive-group guided strategy to prepare atomically dispersed nickel catalysts on red phosphorus. The hydrothermal treatment of red phosphorus leads to the formation of P−H and P−OH groups, which behave as the reactive functionalities to generate the dual structure of single-atom P−Ni and P−O−Ni catalytic sites. The produced single-atom sites provide two different functions: P−Ni for water reduction and P−O−Ni for water oxidation. Benefitting from this specific Janus structure, Ni-red phosphorus shows an elevated hydrogen evolution rate compared to Ni nanoparticle-modified red phosphorus under visible-light irradiation. The hydrogen evolution rate was additionally enhanced with increased reaction temperature, reaching 91.51 μmol h⁻¹ at 70 °C, corresponding to an apparent quantum efficiency of 8.9 % at 420 nm excitation wavelength
Long-Term Safety and Efficacy of Deutetrabenazine in Younger and Older Patients With Tardive Dyskinesia
No full textObjectives: To assess long-term safety and efficacy of deutetrabenazine in younger (\u3c55 years) and older (≥55 years) adult participants with tardive dyskinesia (TD). Design: Three-year, single-arm, open-label extension (OLE) study enrolling participants who completed the 12-week, pivotal ARM-TD or AIM-TD studies. Setting: Seventy-six centers in the United States and Europe. Participants: A total of 337 participants with TD (119 younger and 218 older). Intervention: Deutetrabenazine was initiated at 12 mg/day and titrated once weekly by 6 mg/day using a response-driven dosing regimen until adequate dyskinesia control was reached or a clinically significant adverse event occurred. Measurements: This post hoc analysis assessed change and percent change from baseline in total motor Abnormal Involuntary Movement Scale (AIMS) score, response rates for ≥50% AIMS improvement, Clinical Global Impression of Change (CGIC), Patient Global Impression of Change (PGIC), and safety in younger and older participants with TD. Results: After 3 years of open-label treatment, mean deutetrabenazine dose was ∼39.5 mg/day in both groups. Mean±SE changes from baseline in total motor AIMS score were –6.7 ± 0.62 and –6.5 ± 0.47 in younger and older participants, respectively (percent changes: –61.4% ± 4.10% and –54.6% ± 3.01%); 76% of younger and 62% of older participants achieved ≥50% AIMS response. Most younger and older participants achieved treatment success per CGIC (67% and 76%) and PGIC (64% and 63%). Deutetrabenazine was generally well tolerated in both groups. Conclusions: Deutetrabenazine treatment was associated with sustained improvements in total motor AIMS score, treatment success, and improved quality of life, and was well tolerated in younger and older adults with TD in this 3-year OLE study
Symptom Severity Mixity in Older-Age Bipolar Disorder: Analyses From the Global Aging and Geriatric Experiments in Bipolar Disorder Database (GAGE-BD)
No full textObjective: Some individuals with bipolar disorder (BD) experience manic and depressive symptoms concurrently, but data are limited on symptom mixity in older age bipolar disorder (OABD). Using the Global Aging & Geriatric Experiments in Bipolar Disorder Database, we characterized mixity in OABD and associations with everyday function. Methods: The sample (n = 805), from 12 international studies, included cases with both mania and depression severity ratings at a single timepoint. Four mixity groups were created: asymptomatic (A), mixed (Mix), depressed only (Dep), and manic only (Man). Generalized linear mixed models used mixity group as the predictor variable; cohort was included as a random intercept. Everyday function was assessed with the Global Assessment of Functioning score. Results: Group proportions were Mix (69.6%; n = 560), followed by Dep (18.4%; n = 148), then A (7.8%; n = 63), then Man (4.2%; n= 34); levels of depression and mania were similar in Mix compared to Dep and Man, respectively. Everyday function was lowest in Mix, highest in A, and intermediate in Man and Dep. Within Mix, severity of depression was the main driver of worse functioning. Groups differed in years of education, with A higher than all others, but did not differ by age, gender, employment status, BD subtype, or age of onset. Conclusions: Mixed features predominate in a cross-sectional, global OABD sample and are associated with worse everyday function. Among those with mixed symptoms, functional status relates strongly to current depression severity. Future studies should include cognitive and other biological variables as well as longitudinal designs to allow for evaluation of causal effects
Analyzing Modeled Torque Profiles to Understand Scale-Dependent Active Muscle Responses in the Hip Joint
No full textAnimal locomotion is influenced by a combination of constituent joint torques (e.g., due to limb inertia and passive viscoelasticity), which determine the necessary muscular response to move the limb. Across animal size-scales, the relative contributions of these constituent joint torques affect the muscular response in different ways. We used a multi-muscle biomechanical model to analyze how passive torque components change due to an animal’s size-scale during locomotion. By changing the size-scale of the model, we characterized emergent muscular responses at the hip as a result of the changing constituent torque profile. Specifically, we found that activation phases between extensor and flexor torques to be opposite between small and large sizes for the same kinematic motion. These results suggest general principles of how animal size affects neural control strategies. Our modeled torque profiles show a strong agreement with documented hindlimb torque during locomotion and can provide insights into the neural organization and muscle activation behavior of animals whose motion has not been extensively documented
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