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Bacteriorhodopsin (bR), a pivotal light-driven proton pump intricately associated with the purple membrane (PM) and lipids, demonstrates considerable promise for diverse applications in nanotechnology and technical fields, owing to its distinctive crystalline structure. The removal of lipids from bR is often imperative, contingent upon the specific research objectives, with established methodologies typically relying on chemical detergents like CHAPS, Sodium Cholate, and Triton X-100. In this innovative investigation, we introduce chitosan as a novel delipidation agent, capitalizing on its sustainable, eco-friendly, and cost-effective characteristics, notably its capacity for cationic lipid binding. Derived from chitin, a component of crustaceans, chitosan emerges as a versatile biomaterial with extensive utility. Through a meticulous review of the literature, we present the inaugural utilization of chitosan for bR delipidation. The purification of bR was accomplished utilizing an aqueous two-phase system (ATPS), with the efficacy of lipid removal verified through meticulous analyses employing SDS-Page and UV–Vis Spectrum techniques. The successful application of chitosan in bR delipidation not only underscores its potential as a sustainable alternative to traditional chemical detergents but also prompts further exploration into biomaterial-based nanotechnological pursuits, thus broadening the horizons of scientific inquiry and innovation.

Considering the high rates of pneumococcal resistance reported for several antibiotics, alternatives are urgently needed. In the present study, we report a Streptococcus pneumoniae -targeting endolysin with even greater activity than Cpl-1, the most characterized pneumococcal endolysin to date. We have employed a combination of biochemical and microbiological assays to assess the stability and lytic potential of SP-CHAP and demonstrate its efficacy on pneumococcal biofilms in vitro and in an in vivo mouse model of colonization. Our findings highlight the therapeutic potential of SP-CHAP as an antibiotic alternative to treat Streptococcus pneumoniae infections.

The major drawback associated with PEEK implants is their biologically inert surface, which caused unsatisfactory cellular response and poor adhesion between the implants and surrounding soft tissues against proper bone growth. In this study, polyetheretherketone (PEEK) was incorporated with calcium hydroxyapatite (cHAp) to fabricate a PEEK–cHAp biocomposite, using the fused deposition modeling (FDM) method and a surface treatment strategy to create microporous architectures onto the filaments of PEEK lattice scaffold. Also, nanostructure and morphological tests of the PEEK–cHAp biocomposite were modeled and analyzed on the FDM-printed PEEK–cHAp biocomposite sample to evaluate its mechanical and thermal strengths as well as in vitro cytotoxicity via a scanning electron microscope (SEM). A technique was used innovatively to create and investigate the porous nanostructure of the PEEK with controlled pore size and distribution to promote cell penetration and biological integration of the PEEK–cHAp into the tissue. In vivo tests demonstrated that the surface-treated micropores facilitated the adhesion of newly regenerated soft tissues to form tight implant–tissue interfacial bonding between the cHAp and PEEK. The results of the cell culture depicted that PEEK–cHAp exhibited better cell proliferation attachment spreading and higher alkaline phosphatase activity than PEEK alone. Apatite islands formed on the PEEK–cHAp composite after immersion in simulated body fluid of Dulbecco's modified Eagle medium (DMEM) for 14 days and grew continuously with more or extended periods. The microstructure treatment of the crystallinity of PEEK was comparatively and significantly different from the PEEK–cHAp sample, indicating a better treatment of PEEK–cHAp. The in vitro results obtained from the PEEK–cHAp biocomposite material showed its biodegradability and performance suitability for bone implants. This study has potential applications in the field of biomedical engineering to strengthen the conceptual knowledge of FDM and medical implants fabricated from PEEK–cHAp biocomposite materials.

The health effects associated with particulate matter (PM) are extensively reported; nevertheless, limited research has explored the exact contributions of its chemical constituents to physical dysfunctional aging. This study assesses the relationships between prolonged exposure to significant ambient air pollutants, especially ammonium (NH 4 + ), and physical dysfunction in a nationally representative cohort of older Chinese adults. We investigated data from 14,641 participants aged 45 years or older in the 2015 wave of the China Health and Retirement Longitudinal Study (CHARLS), which was integrated with high-resolution air pollution data from the ChinaHighAirPollutants (CHAP) dataset. Physical dysfunction was evaluated by self-reported challenges in executing routine activities. After controlling for a wide range of confounders, associations among eight air contaminants (averaged from 2013 to 2015) and dysfunction risk were investigated using logistic regression models. Multicollinearity among covariates in the fully adjusted models was assessed using the generalized variance inflation factor (GVIF), with a threshold value of 5 adopted as the criterion to indicate potential collinearity. Sensitivity analyses—including exclusion of high-exposure participants, standardized z-score modeling, stratified subgroup evaluations, and multipollutant adjustments—were performed to assess the robustness of associations. Dose–response relationships were modeled using both quartile-based logistic regression and restricted cubic spline (RCS) models, revealing consistent and complementary trends. To estimate independent effects and address potential collinearity, we further constructed a multipollutant model adjusting for seven co-pollutants. In all and fully adjusted models, ambient ammonium (NH 4 + ) was the only air pollutant that demonstrated a significant and independent association with physical dysfunction (OR: 1.03; 95% CI: 1.01–1.05; p  < 0.05); no significant associations were found for the other pollutants. This association remained robust across multiple sensitivity analyses, including exclusion of extreme exposure (OR: 1.13; 95% CI: 1.08–1.17; p  < 0.001), z-score standardization (OR: 2.17; 95% CI: 1.57–2.98; p  < 0.001), and 5 stratified subgroup models. A significant dose–response relationship was identified both in quartile-based trend tests (p for trend < 0.001) and restricted cubic spline analysis (p for non-linearity < 0.001). Taken together, the monotonic trend from quartile analysis and the non-linear pattern from spline modeling suggest that even moderate exposure to NH4⁺ may contribute to physical dysfunction. Furthermore, multicollinearity diagnostics based on generalized variance inflation factors (GVIFs) indicated no evidence of problematic collinearity among covariates in the fully adjusted models (all GVIF < 5). Besides, the association remained significant and became stronger in a multipollutant model, highlighting the independent effect of NH 4 + beyond co-pollutant confounding (OR: 1.49; 95% CI: 1.26–1.76; p  < 0.001). Our findings indicate that NH 4 + , a significant secondary component of PM predominantly sourced from agricultural ammonia emissions, may uniquely contribute to the deterioration of physical function. It may be important to evaluate particle chemical makeup for analyzing health concerns, as there is no association for total PM mass. Long-lasting exposure to ambient NH 4 + has been independently associated with increased odds of physical dysfunction across older adults in China. These findings underscore the necessity for specific environmental strategies focused on ammonia reduction to alleviate age-related functional deterioration and foster healthy aging.

The utility of CHAPS-PC, a detergent combination for solubilizing membrane proteins, was investigated as a substitute to digitonin solution for extracting rhodopsin in the measurement of spectral sensitivity in squid. Microvilli of the photoreceptor outer segments were collected and purified from the retinas of three species, Uroteuthis edulis, Todarodes pacificus, and Heterololigo bleekeri, using sucrose density-gradient centrifugation. The difference in the absorption maximum (λmax) of rhodopsin between extraction with CHAPS-PC or with digitonin was 0–3 nm for all species. The λmax values of the three squid species were 488–490, 478–480, and 488–491 nm, respectively, which aligns well with values reported in previous studies. CHAPS and PC are less expensive than digitonin, which is advantageous when conducting repeated experiments. We hope that the present procedure for the extraction of visual pigments offers an improved fisheries technology that will be used to better understand the ecology of diverse squid species.

Background: Identification of auditory processing disorders is achieved using questionnaires along with linguistic, non-linguistic, and auditory processing tests. Notably, the questionnaires “Children’s Auditory Performance Scale” (CHAPS) and “Auditory Processing Domain Questionnaire” (APDQ) are widely recognized and used. The current study investigated the psychometric properties of the CHAPS and APDQ in Greek Cypriot children. Methods: The CHAPS and APDQ questionnaires were completed by parents of 40 Greek Cypriot children, 16 typically developing (TD) children, and 24 children with a history of Speech Sound Disorders (SSDs). Results: There were significant differences between the two groups on both questionnaires. Cronbach’s alpha was calculated at α = 0.922 for the CHAPS total score and α = 0.926 for the APDQ total score. The Receiver Operating Curve (ROC) analysis provided a cut-off point equal to −0.30 (AUC 0.849, p < 0.001) for CHAPS and a cut-off point equal to 90.00 (AUC 0.820, p < 0.001) for APDQ. Significant positive Spearman ρ correlations were observed between the CHAPS and APDQ (ρ = 0.639, p = 0.001). Conclusions: The CHAPS and APDQ can identify distinct auditory processing characteristics between in children with SSDs and TD children.

Chronic alcohol consumption can lead to tolerance and escalation of drinking in humans and animals, but mechanisms underlying these changes are not fully characterized. Preclinical models can delineate which mechanisms are involved. The chronic intermittent ethanol exposure (CIE) procedure uses forced exposure to vaporized alcohol that elicits withdrawal and increased responding for alcohol in operant tasks in C57BL/6J inbred mice. Chronic two-bottle choice (2BC) drinking in the same strain elicits abstinent-related depression-like behavior, suggestive of allostatic changes. Selected lines such as crossed High Alcohol Preferring (cHAP) mice voluntarily drink to blood alcohol concentrations comparable to those attained in CIE and could be used to assess how alcohol affects these same endpoints without the confounds of involuntary vapor inhalation. In three experiments, we assess how 2BC drinking in cHAP mice affects abstinence-related depressive- and anxiety-like behavior, operant responding for alcohol, and binge consumption using drinking-in-the-dark (DID). We hypothesized that cHAPs with home-cage drinking experience would exhibit more depressive behavior after abstinence, increased responding for alcohol in the operant box, and increased DID intake. Of these, a drinking history increased DID intake in female cHAPs only and increased sucrose preference and intake following abstinence, but had no effects on operant responding or NSFT latency and FST immobility following forced abstinence. These results are consistent with recent findings using slice electrophysiology showing tolerance to alcohol's actions on the dorsolateral striatum following 2BC drinking in female, but not male cHAP mice. Overall, these data suggest that cHAPs may require procedures allowing rapid intoxication, such as DID, to demonstrate changes in alcohol's rewarding effects. •Up to 3 weeks of abstinence from 2BC drinking did not induce affective disturbance.•Alcohol drinking experience did not change operant responding for alcohol.•Alcohol drinking experience did not change extinction responding for alcohol.•Alcohol experience increased intake in drinking-in-the-dark in female cHAPs only.•During DID, alcohol experience caused more persistent binge-like behavior.

Wound healing represents a complex biological process often hampered by bacterial infections, in particular those caused by Staphylococcus aureus, which is already multiresistant to many antibiotics. In this sense, enzybiotics have additional advantages over conventional antibiotics, since they provide pathogen specificity and do not contribute to antibiotic resistance. However, their soluble administration at the wound site would result in enzyme leakage. On the other hand, bacterial cellulose (BC) pellicles present a very promising dressing and scaffold, given its high purity, water retention capacity, and barrier effect in the wound against possible contaminants. In this study, we present a novel approach that incorporates the enzybiotic CHAPK into BC to develop functionalized membranes that exhibit targeted and controlled antimicrobial activity against S. aureus. The kinetic tests revealed a continuous loading of the enzybiotic into BC until it reaches a maximum and a two-stage release process, characterized by an initial fast release followed by a sustained release. Attenuated total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), and Confocal Laser Scanning Microscopy (CLSM) confirmed the incorporation and the preferential surface localization of CHAPK within the BC membranes. Finally, the BC/CHAPK materials demonstrated the sustained reduction of up to 4 logarithmic units in the viability of S. aureus. Overall, the biomaterials developed here exhibit promising antimicrobial efficacy against S. aureus, offering a potential strategy for wound management and skin infection control while maintaining unharmed the commensal skin microbiota, which impairment could compromise the integrity of the skin barrier function.

Bovine mastitis is the most important infectious disease, causing significant losses in the dairy industry, in which Streptococcus agalactiae is a major pathogen. In this study, lysin CHAPk, derived from bacteriophage K, was expressed heterogeneously, and its antimicrobial and anti-biofilm effects against S. agalactiae isolated from bovine mastitis were further analyzed. CHAPk was expressed in Escherichia coli BL21 (DE3), in which the purified yield of CHAPk was up to 14.6 mg/L with the purity of 95%. Time-killing kinetic curves showed that CHAPk fastly killed S. agalactiae in TSB medium and in milk within 25 min (by 3.3 log10 CFU/mL and 2.4 log10 CFU/mL, respectively). Observation of scanning electron microscope (SEM) showed cells wrinkled and ruptured after the treatment of CHAPk. CHAPk effectively inhibited early biofilms by 95% in 8 × MIC, and eradicated mature biofilms by 89.4% in 16 × MIC. Moreover, CHAPk killed 99% bacteria in mature biofilms. Confocal laser scanning microscopy (CLSM) also demonstrated the potent antimicrobial and anti-biofilm action of CHAPk. It was firstly demonstrated CHAPk had the characters of inhibition/elimination of S. agalactiae biofilms and killing the bacteria in biofilms. CHAPk has the potential to develop a new antibacterial agent for mastitis treatment of S. agalactiae infections.

Cardiovascular disease (CVD) is a prevalent global health issue and one of the leading causes of death. Aging and air pollution are well-established risk factors for CVD. This study aims to investigate the association between air pollutants (sulfur dioxide, carbon monoxide, PM1, PM2.5, nitrogen dioxide, ozone) and the risk of heart disease. Utilizing data from the China Health and Retirement Longitudinal Study (CHARLS) and the China High Air Pollutants (CHAP) database, we employed multivariable-adjusted logistic regression to analyze the relationship between pollutants and heart disease. Additionally, six binary classification machine learning algorithms—AdaBoost, Decision Tree, LightGBM, XGBoost, Random Forest, and GBDT—were used to construct predictive models. The models incorporated air pollutant concentrations (SO₂, CO, PM1, etc.) as core features, along with covariates such as gender, age, and hypertension. The data were split into an 80% training set and a 20% test set, with cross-validation applied to ensure robustness. Multivariable regression analysis revealed that after adjusting for multiple covariates (including BMI, blood glucose, and other pollutants), each 1-unit increase in SO₂ concentration was associated with an odds ratio (OR) of 1.040 for heart disease (95% confidence interval [CI]: 1.027–1.054, p  < 0.00001). Among the machine learning models, Random Forest exhibited the best performance, with an AUC of 0.794 in the training set and 0.726 in the test set. SHAP analysis confirmed that SO₂ was the most impactful pollutant. Subgroup analysis indicated a significant interaction between SO₂ and household registration type ( p  < 0.05). Future research should further explore the mechanisms underlying SO₂-induced cardiac damage and optimize the applicability of predictive models.