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Targeted incorporation of collagen IV to the basement membrane: A step forward for developing extracellular protein therapies
Central optical power of the isolated human lens without zonular tension
The ability to focus at near is achieved by dynamic changes in the shape of the lens of the eye. The Helmholtz hypothesis of accommodation proposes that, at distance gaze, all of the lenticular supporting zonules are at maximal tension. To bring a near object into focus, this tension is reduced by action of the ciliary muscle. The resultant release of tension allows the elastic lens capsule to mold the lens into a more rounded shape, increasing both its central thickness and central optical power (COP). Based upon Helmholtz’s hypothesis, complete removal of these zonules should result in a rounded shaped lens of maximal COP. Schachar has offered an alternative mechanism of accommodation based upon the distinct actions of the three different groups of lenticular zonules. Schachar believes that for distant objects, all the zonules are under the minimum tension required to maintain lens stability; however, during lenticular accommodation, equatorial zonular tension increases while, simultaneously, the anterior and posterior zonular tension decreases. The selective increase in equatorial zonular tension results from the unique orientation of the different ciliary muscle fiber groups. With this increase in equatorial zonular tension, the peripheral lens surfaces flatten, central surfaces steepen and central lens thickness and COP increase. Schachar’s hypothesis would anticipate that with zonular removal, the COP of the isolated lens would be minimal and diametrically opposite to the high lens COP expected with the Helmholtz hypothesis. In order to determine the COP of the isolated human lens, we obtained, through the kindness of the authors of an independent research study, the x-y coordinates of the central sagittal lens profiles of 10 freshly isolated human lenses (donors aged 20–30 years). These coordinate data were then mathematically utilized by fitting them into Chien, Forbes, Fourier, and elliptical equations. Additionally, the coordinate data was smoothed and fit to third-degree polynomials (S4W 3rd Poly). Independent of which of these equations was employed, within central optical zone diameters of ≤ 3 mm, the COP was found to be minimal. Since the S4W 3rd Poly provided the best fit, it was used to represent lens surfaces in optically modeled eyes. In all modeled eyes, Zernike spherical aberration (SA) coefficients were positive. These findings are consistent with in vivo measurements of SA obtained from human eyes while viewing distant visual objects. Having thus demonstrated that freshly removed human lenses, free of zonular tension, have their least COP, it is likely that this condition mimics the physiologic status of the human lens in the eye while attending to the most distant visual objects. In an independent, companion paper, we observed, using interferometric measurements of surface radius of curvatures of 12 fresh, isolated human lenses, obtained from donors aged 20–30 years, that the minimal COP was also associated with the unaccommodated state in vivo.
Understanding the role of urban block morphology in innovation vitality through explainable machine learning
A new digital watermarking model using honey encryption and reversible cellular automata
Unveiling the genetic basis of floral scent formation in roses using weighted gene co-expression and protein-protein interaction network analyses
A reasoning algorithm with the original relations of the 3D basic rectangular cardinal direction relation
Design and performance optimization of circularly polarized luminescent materials based on lanthanide helicates
Cardiac and behavioural trends in toddler pain distress responses across early development
Binary curcuminoid complex CRE-Bin inhibits osteoclast differentiation by suppressing the canonical NF-κB signaling pathway and modulating microRNA-223 expression
Fabrication and evaluation of solidified nanoemulsion designs for systemic delivery of atorvastatin through the lung
Circular RNA-OGDH promotes PANoptosis in diabetic cardiomyopathy: A novel mechanistic insight
A computational study exploring echinoderm-derived compounds for inhibition of aminoglycoside acetyltransferases
Aminoglycoside acetyltransferases (AACs) catalyze the acetylation of aminoglycoside antibiotics, playing a major role in bacterial resistance and posing a serious threat to global healthcare. Despite growing interest in natural products, echinoderm-derived metabolites remain largely unexplored as AAC inhibitors. This study presents a comprehensive in-silico investigation into the potential of these marine compounds to inhibit four key AAC enzymes: Aminoglycoside 2′-N-acetyltransferase, AAC(3)-Ib, AAC(6′)-Im, and AAC(3)-Iva. A virtual screening of 1600 echinoderm metabolites was performed using molecular docking, ADMET profiling, and 100 ns molecular dynamics simulations. The top 10 compounds against each enzyme were shortlisted based on binding affinity, with CMNPD15515, CMNPD17440, CMNPD3088, and CMNPD29853 showing the most stable interactions and highest binding energies. These compounds consistently outperformed native aminoglycoside ligands in docking scores and MMGBSA binding free energy calculations, suggesting stronger inhibitory potential. While a few top hits exhibited violations of Lipinski’s Rule of Five particularly in molecular weight their strong target engagement and stable dynamic profiles support their candidacy as lead molecules. This work underscores the evolutionary and structural uniqueness of echinoderm metabolites as a promising reservoir for antibiotic adjuvants. It also establishes a computational framework for prioritizing marine natural products against antibiotic resistance targets. Although experimental validation remains essential, this study provides compelling early evidence to guide future in vitro and in vivo research toward the development of novel AAC inhibitors.
Intestinal permeability and its relation to anthropometric and biochemical variables associated with cardiovascular risk in an elderly population
Abstract Aging reduces functional capacity, decreasing lean mass and immune function, possibly impacting the intestinal morphofunctional barrier. This study aimed to characterize intestinal permeability in an elderly population and its association with anthropometric and biochemical variables associated with cardiovascular risk. A cross-sectional study was conducted with 54 elderly individuals from Oct/19-Mar/23. Self-reported disease, anthropometric (weight, height, waist, and hip circumferences), and biochemical (lipid profile, glycemic, and serum retinol) data were collected. Intestinal permeability was assessed using the lactulose: mannitol (L: M) test, and stratified into percentile ≤ 50 or > 50. Diabetes, hypertension, and overweight were present in 25.9%, 53.7%, and 51.9% of the population, with no significant differences between those with L: M ≤ P50 or > P50. Median L: M was 0.037 (0.014; 0.060). Those with L: M > P50 had significantly lower levels of hip circumference [96.50 (93; 104) cm; P = 0.041] and serum retinol [0.95 (0.60; 1.16) mmol/L; P < 0.001], and these variables were also inversely associated with an odds for a L: M > P50 (AOR 0.93, 95% CI 0.86–0.99; P = 0.042; AOR 0.15, 95% CI 0.05–0.42; P < 0.001, respectively). We concluded that hip circumference and serum retinol were negatively associated with intestinal permeability in the studied elderly, and data indicate that lactulose and mannitol were positively associated with anthropometric and biochemical markers related to metabolic complications.
Machine learning of time series data using persistent homology
Abstract This study proposes a novel method for time-series analysis based on persistent homology. Traditional time-series analysis techniques based on persistent homology often involve high computational costs. To address this challenge, we introduce the use of recurrence plots. In our approach, recurrence plots are first generated from the datasets, and topological information is then extracted from these plots using persistent homology. The obtained topological information are vectorized through persistence image and the resulting vectors are further reduced using non-negative matrix factorization. The features derived from this method encapsulate rich and distinctive information inherent in the dataset. We applied the proposed approach to several synthetic and experimental datasets to demonstrate its effectiveness. Our method successfully identified the periodic-to-chaotic and chaotic-to-chaotic transitions in Chua’s system and revealed distinguishing characteristics in electromyograms from healthy, neuropathic, and myopathic individuals. Additionally, the extracted features enabled accurate classification of electrocardiogram data. Overall, the results indicate that the features obtained through this method capture essential information embedded in time-series data.
PMSM integral sliding mode control based on improved power exponential reaching law
Evolution law of microporous structure in cement asphalt (CA) mortar under the action of polyurethane polycarboxylates
CD133 defines hair-inductive cells in the dermal papilla
The impact of SERE training on selected neurotransmitter secretion in special forces soldiers
The role of difficulties in emotion regulation on non-suicidal self-injury and suicide attempts: a cross-sectional study of Chinese adolescents
Abstract Non-suicidal self-injury (NSSI) and suicide attempts (SA) among adolescents are issues of widespread concern. Non-suicidal self-injury and attempted suicide are both risk factors for suicide, and difficulties in emotion regulation (DER) may play a crucial role in their occurrence. Therefore, our study aims to investigate the role of DER in NSSI and SA among adolescents, which is of substantial clinical importance for the prevention and intervention of adolescent suicidal behaviors. A web-based questionnaire survey was administered to 9140 Chinese adolescents aged 12–18 years. Utilizing chain mediation and a threshold effect model, we investigated the impact of DER in relation to NSSI and SA among adolescents. DER had a direct and indirect effect on NSSI severity by amplifying depressive symptoms, which consequently increased the severity of NSSI. Furthermore, DER directly elevated the risk of SA by exacerbating depressive symptoms and NSSI severity. We observed a threshold effect, whereby the DER significantly increased the severity of NSSI after reaching a threshold score of 87. Our study provides valuable insights into the psychological mechanism of DER in relation to NSSI and SA among Chinese adolescents, underscoring the importance of intervention and prevention strategies aimed at addressing these underlying difficulties. These findings contribute to research on adolescent suicide and fill a knowledge gap in this field.