Browse Articles

Magnetochiral charge pumping due to charge trapping and skin effect in chirality-induced spin selectivity

Impact of posterior septectomy on olfaction in endoscopic endonasal transsphenoidal surgery

Background Endoscopic endonasal transsphenoidal surgery is widely used to resect pituitary adenomas, yet its impact on olfactory function after resection of the posterosuperior nasal septum remains a concern. To optimize surgical techniques to preserve olfactory function, it is essential to understand the relationship between the extent of septal resection and olfactory outcomes. Methods This retrospective study analyzed 295 patients who underwent pituitary adenoma surgery. The extent of nasal septum resection was quantified and its impact on olfactory function was assessed using the Cross-Cultural Smell Identification Test (CCSIT), Sino-Nasal Outcome Test-22 (SNOT-22), and a Visual Analog Scale (VAS) for olfactory loss. Preoperative and 6-month postoperative scores were compared to evaluate changes in olfactory function. Results There was a significant correlation between larger septal resections and greater reductions in CCSIT scores, indicating a decline in olfactory function. Furthermore, patients with more extensive septal resections reported increased discomfort and olfactory loss, as evidenced by higher SNOT-22 and VAS scores. These findings highlight the importance of the nasal septum in maintaining laminar airflow and its role in olfactory function. Conclusion Study underscores the adverse effects of extensive posterior septectomy on olfactory outcomes. Minimizing the extent of septal resection may help preserve olfactory function, suggesting a need for surgical strategies that maintain septum integrity to reduce the risk of postoperative olfactory impairment.

Decoding the general role of tRNA queuosine modification in eukaryotes

RETRACTED ARTICLE: Improving the power production efficiency of microbial fuel cell by using biosynthesized polyanaline coated Fe3O4 as pencil graphite anode modifier

Optimizing qubit performance through smoothing techniques

Molecular properties of the RmlT wall teichoic acid rhamnosyltransferase that modulates virulence in Listeria monocytogenes

Machine learning derived retinal pigment score from ophthalmic imaging shows ethnicity is not biology

AbstractFew metrics exist to describe phenotypic diversity within ophthalmic imaging datasets, with researchers often using ethnicity as a surrogate marker for biological variability. We derived a continuous, measured metric, the retinal pigment score (RPS), that quantifies the degree of pigmentation from a colour fundus photograph of the eye. RPS was validated using two large epidemiological studies with demographic and genetic data (UK Biobank and EPIC-Norfolk Study) and reproduced in a Tanzanian, an Australian, and a Chinese dataset. A genome-wide association study (GWAS) of RPS from UK Biobank identified 20 loci with known associations with skin, iris and hair pigmentation, of which eight were replicated in the EPIC-Norfolk cohort. There was a strong association between RPS and ethnicity, however, there was substantial overlap between each ethnicity and the respective distributions of RPS scores. RPS decouples traditional demographic variables from clinical imaging characteristics. RPS may serve as a useful metric to quantify the diversity of the training, validation, and testing datasets used in the development of AI algorithms to ensure adequate inclusion and explainability of the model performance, critical in evaluating all currently deployed AI models. The code to derive RPS is publicly available at: https://github.com/uw-biomedical-ml/retinal-pigmentation-score.

Predicting prosthetic gait and the effects of induced stiff-knee gait

Prosthetic gait differs considerably from the unimpaired gait. Studying alterations in the gait patterns could help to understand different adaptation mechanisms adopted by these populations. This study investigated the effects of induced stiff-knee gait (SKG) on prosthetic and healthy gait patterns and the capabilities of predictive simulation. Self-selected speed gait of two participants was measured: one healthy subject and one knee disarticulation subject using a variable-damping microprocessor controlled knee prosthesis. Both performed unperturbed gait and gait with restricted knee flexion. Experimental joint angles and moments were computed using OpenSim and muscle activity was measured using surface electromyography (EMG). The differences between the conditions were analyzed using statistical parametric mapping (SPM). Predictive models based on optimal control were created to represent the participants. Additionally, a hypothetical unimpaired predictive model with the same anthropometric characteristics as the amputee was created. Some patterns observed in the experimental prosthetic gait were predicted by the models, including increased knee flexion moment on the contralateral side caused by SKG in both participants, which was statistically significant according to SPM. With the exception of the rectus femoris muscle, we also found overall good agreement between measured EMG and predicted muscle activation. We predicted more alterations in activation of the hip flexors than other muscle groups due to the amputation and in the activation of the biceps femoris short head, quadratus femoris, and tibialis anterior due to SKG. In summary, we demonstrated that the method applied in this study could predict gait alterations due to amputation of the lower limb or due to imposed SKG.

Chemotherapeutic hormesis induced by the tumor microenvironment in refractory ovarian cancer

Ironing out differences in attenuation and blooming artifact in acute stroke thrombi

AbstractThis study aims to improve our understanding of acute ischemic stroke clot imaging by integrating CT attenuation information with MRI susceptibility signal of thrombi. For this proof-of-principle experimental study, fifty-seven clot analogs were produced using ovine venous blood with a broad histological spectrum. Each clot analog was analyzed to determine its RBC content and chemical composition, including water, Fe III, sodium, pH, and pO2. Non-contrast CT and a susceptibility-weighted MRI sequence were used for imaging. The study found that RBC content correlated more accurately than iron content with clot attenuation on CT. There was a strong correlation between Fe III content and RBC percentage in clots. Specifically, changes in RBC content accounted for 64% of the variance in Fe III content (R2 = 0.640; p < .0001). Thrombi with blooming artifacts (BA) displayed higher attenuation on non-contrast CT than those without (73.4 vs. 40 HU, p < .0001) and had the highest RBC and iron contents. The cut-off value of 1242 µg/g of iron predicted blooming artifacts with high sensitivity and specificity. The pH level strongly affected the appearance of blooming artifacts, particularly for negative clots with high RBC content. These findings provide significant insights into the imaging behavior of acute ischemic stroke clots across both imaging modalities and could potentially improve the diagnosis and treatment of acute stroke patients. Furthermore, these results open the possibility for future research aimed at developing pH-modulated therapeutic strategies based on the acid-base state of thrombi.

Mechanisms of concentration control alkali activated fly ash stabilized saline soil in seasonally frozen regions

Limitations of ice cores in reconstructing temperature seasonality

MCM2-7 ring closure involves the Mcm5 C-terminus and triggers Mcm4 ATP hydrolysis

AbstractThe eukaryotic helicase MCM2-7, is loaded by ORC, Cdc6 and Cdt1 as a double-hexamer onto replication origins. The insertion of DNA into the helicase leads to partial MCM2-7 ring closure, while ATP hydrolysis is essential for consecutive steps in pre-replicative complex (pre-RC) assembly. Currently it is unknown how MCM2-7 ring closure and ATP-hydrolysis are controlled. A cryo-EM structure of an ORC-Cdc6-Cdt1-MCM2-7 intermediate shows a remodelled, fully-closed Mcm2/Mcm5 interface. The Mcm5 C-terminus (C5) contacts Orc3 and specifically recognises this closed ring. Interestingly, we found that normal helicase loading triggers Mcm4 ATP-hydrolysis, which in turn leads to reorganisation of the MCM2-7 complex and Cdt1 release. However, defective MCM2-7 ring closure, due to mutations at the Mcm2/Mcm5 interface, leads to MCM2-7 ring splitting and complex disassembly. As such we identify Mcm4 as the key ATPase in regulating pre-RC formation. Crucially, a stable Mcm2/Mcm5 interface is essential for productive ATP-hydrolysis-dependent remodelling of the helicase.

ATLAS-seq: a microfluidic single-cell TCR screen for antigen-reactive TCRs

Gut microbiota dysbiosis, sarcopenia, osteoporosis and osteosarcopenia in older people: A systematic review protocol

Introduction Sarcopenia and Osteoporosis are two prevalent conditions in the older population and are defined by low strength, muscle quality/volume and low Bone Mineral Density, respectively. When there is a concomitant presence of both, there is a novel musculoskeletal condition called Osteosarcopenia. These conditions adversely affect quality of life and elevate the risk of fractures, disability, and mortality among older individuals. Dysbiosis of the gut microbiota is the impairment of the mutualistic relationship between microorganisms, metabolic products and the host’s immune system. Gut microbiota dysbiosis could be intricately linked to sarcopenia and osteoporosis, shedding light on the complex microbiota-gut-bone-muscle axis. Furthermore, the intestinal microbiota experiences a notable decline in beneficial microorganisms as part of the aging process. The relationship between dysbiosis of the intestinal microbiota in older people and sarcopenia, osteoporosis or osteosarcopenia is still unclear. This review protocol aims to systematically review the literature and compile evidence on the influence of gut microbiota dysbiosis on musculoskeletal function in older people with sarcopenia, osteoporosis or osteosarcopenia. Methods/Analysis This systematic review will analyze observational studies that have investigated the relationship between the effects of gut microbiota dysbiosis and sarcopenia, osteoporosis and osteosarcopenia in older people aged 65 and over. Studies will be retrieved from PubMed/MEDLINE, EMBASE, Scopus, Web of Science and the Cochrane Library. Outcome measures will include body composition for diagnosing osteoporosis and screening for sarcopenia/osteosarcopenia by any criteria. Data synthesis will involve quantitative analysis using summary measures. If sufficient studies, homogeneity and heterogeneity analysis will be performed to conduct Meta-analysis and pooled OR, RR and HR measures will be provided.

Adaptive hip exoskeleton control using heart rate feedback reduces oxygen cost during ecological locomotion

Abstract Despite their potential, exoskeletons have not reached widespread adoption in daily life, partly due to the challenge of seamlessly adapting assistance across various tasks and environments. Task-specific designs, reliance on complex sensing and extensive data-driven training often limit the practicality of the existing control strategies. To address this challenge, we introduce an adaptive control strategy for hip exoskeletons, emphasizing minimal sensing and ease of implementation. Using only insole pressure and heart rate (HR) sensing, the controller modulates assistance across various locomotor tasks. We evaluated this strategy with twelve able-bodied participants in a real-world scenario including level walking, stairs, and inclines. The controller successfully adapted assistance timing and amplitude to different activities. This resulted in effort intensity reductions (measured by oxygen uptake) of up to 12.6% compared to walking with no exoskeleton, and up to 25.5% compared to walking with the exoskeleton in zero-torque mode. Cardiodynamic response of HR, although delayed, proved sufficient for adaptation in tasks lasting longer than around 45 s, and delay-induced limitations primarily affected brief bouts of abrupt change in intensity. However, we found discernible patterns in HR shortly after the onset of such changes that can be exploited to improve responsiveness. Our findings underscore the potential of HR as a promising measure of user effort intensity, encouraging future research to explore its integration into advanced adaptive algorithms.

Two-hit mouse model of heart failure with preserved ejection fraction combining diet-induced obesity and renin-mediated hypertension

Prediction of heavy metal spatial distribution in soils of typical industrial zones utilizing 3D convolutional neural networks

E4F1 coordinates pyruvate metabolism and the activity of the elongator complex to ensure translation fidelity during brain development

AbstractPyruvate metabolism defects lead to severe neuropathies such as the Leigh syndrome (LS) but the molecular mechanisms underlying neuronal cell death remain poorly understood. Here, we unravel a connection between pyruvate metabolism and the regulation of the epitranscriptome that plays an essential role during brain development. Using genetically engineered mouse model and primary neuronal cells, we identify the transcription factor E4F1 as a key coordinator of AcetylCoenzyme A (AcCoA) production by the pyruvate dehydrogenase complex (PDC) and its utilization as an essential co-factor by the Elongator complex to acetylate tRNAs at the wobble position uridine 34 (U34). E4F1-mediated direct transcriptional regulation of Dlat and Elp3, two genes encoding key subunits of the PDC and of the Elongator complex, respectively, ensures proper translation fidelity and cell survival in the central nervous system (CNS) during mouse embryonic development. Furthermore, analysis of PDH-deficient cells highlight a crosstalk linking the PDC to ELP3 expression that is perturbed in LS patients.

Sticky organisms create underwater biological adhesives driven by interactions between EGF- and GlcNAc- containing polysaccharides