Search Results (51,988)

Respiratory support requirement among children hospitalized with pneumonia is a key marker of disease severity and resource needs, yet scalable risk stratification tools for routine hospital settings in Southern Vietnam remain limited. Background: This study aimed to develop and evaluate clinical and laboratory-based multivariable models to predict respiratory support requirement in children under five hospitalized with pneumonia, using a routine care dataset. Methods: We conducted a retrospective cohort study conducted at a tertiary pediatric hospital in Southern Vietnam (July 2024–November 2025), children aged 2–59 months hospitalized with pneumonia were included after predefined exclusions. The outcome was the maximum (worst) level of respiratory support required during hospitalization (oxygen therapy, CPAP, or invasive mechanical ventilation), analyzed as a binary endpoint (any support vs. none) for model development. Candidate predictors included bedside clinical variables (age < 12 months, malnutrition, recurrent pneumonia, cyanosis, tachypnea, chest indrawing) and complete blood count-derived inflammatory indices. Univariable logistic regression was used for crude associations. Two multivariable logistic regression models were built: Model 1 (clinical-only) and Model 2 (clinical + neutrophil-to-lymphocyte ratio [NLR]; primary). Discrimination was assessed using area under the ROC curve (AUC), and calibration was evaluated using the Hosmer–Lemeshow test and observed-to-expected (O:E) ratio. Results: A total of 1797 children were included; 154 (8.6%) required respiratory support. In the primary model, independent predictors were age < 12 months (aOR 2.57, 95% CI 1.69–3.92), malnutrition (aOR 4.33, 2.56–7.33), recurrent pneumonia (aOR 1.82, 1.18–2.81), cyanosis (aOR 24.02, 7.41–77.87), chest indrawing (aOR 4.19, 2.73–6.43), and higher NLR (per 1 unit: aOR 1.49, 1.38–1.60), while tachypnea was not independently associated after adjustment. Discrimination improved from Model 1 (AUC 0.754) to Model 2 (AUC 0.840; 95% CI 0.806–0.874). At the optimal probability cut-off (0.122), Model 2 achieved sensitivity 66.2%, specificity 86.2%, PPV 31.1%, NPV 96.5%, and accuracy 84.5%. Calibration was acceptable (Hosmer–Lemeshow p = 0.662; O:E = 1.00). Conclusions: A simple clinical model strengthened by NLR provided good discrimination and calibration for predicting respiratory support requirement among children under-five hospitalized with pneumonia in Southern Vietnam. This approach may support early triage, prioritization of monitoring intensity, and escalation readiness in resource-constrained settings, although external validation is warranted. Full article

Background/Objectives: The flavonoid quercetin (Q) has recently been suggested as a natural anti-aging and senolytic agent. However, its low stability and poor oral bioavailability may limit its efficacy. To address this, we investigated whether a lecithin-based formulation of Q, Quercefit™ (QF), enhances stress resistance and delays aging in vivo. Methods: The nematode Caenorhabditis elegans was used as an animal model to evaluate the effects of QF under physiological and stress conditions. Unformulated Q was administered as a control. Worm survival, healthspan, resistance to thermal and oxidative stress, and expression of stress- and longevity-related genes were assessed. All the experiments were conducted at least in triplicate, each including a minimum of 15 worms. The data were analyzed using Student’s t-test, one-way or two-way ANOVA, and Bonferroni’s post hoc test. Results: One hundred micromolar Q administered in QF was more effective than equimolar unformulated Q in increasing the worms’ ability to resist acute thermal stress at 35 °C (tested on 75 worms/group) and oxidative stress caused by 0.5 mM hydrogen peroxide (tested on 75 worms/group). In this last case, the protective effect of QF was similar to that of N-acetylcysteine and ascorbic acid. Under experimental conditions mimicking the long-term consequences of thermal stress, QF, like Q, increased the worms’ lifespan and healthspan by approximately 50%, counteracting the age-related decline associated with stress (120 worms/group). These benefits are supported by QF’s capacity to act as a reactive oxygen species scavenger; suppress heat-shock element gene transcription activated by thermal stress, such as hsp-16.2 and hsp-70, and stimulate the sod-3 and gst-4 genes that are involved in antioxidant and detoxification responses. Conclusions: These findings suggest that Q, when administered in the QF formulation, can act at the transcriptional level to protect against aging induced by stressful conditions. Full article

Hypoxia-dependent microRNAs play an important role in orchestrating a plant’s response to low-oxygen stress. To assess the regulatory mechanisms of the adaptive response of maize (Zea mays L.) to hypoxia, an antisense sequence was developed, and the short tandem target mimic (STTM) system was used to induce the loss of function of the mature microRNA775A (miR775a) in maize. A recombinant binary vector pBI121 cloned in E. coli cells containing the antisense sequence anti-miR775A to maize miR775A was acquired to create a line of modified A. tumefaciens EHA105. Using the puncturing method on soaked seeds, maize plants with an active anti-miR775A construct were obtained, as evidenced by a decrease of more than 10-fold in mature miR775A content and by developmental changes in the seedlings. The size of seedlings of the maize knockdown line was almost twice smaller than that of the wild-type (WT) plants. An assessment of the effects of hypoxic conditions induced by flooding of 14-day-old maize plants revealed differences in the expression and activity of several enzymes between WT and knockdown plants. The reduced miR775A levels led to a 2.1-fold drop in pyruvate levels, which resulted in decreased pyruvate kinase, pyruvate dehydrogenase, and lactate dehydrogenase activities as compared to WT plants. A decrease in miR775A content in the maize knockdown cell line also affected the function of mitochondrial and extramitochondrial isoenzymes of citrate synthase, aconitase, and fumarase under hypoxic conditions. Full article

This systematic review aimed to synthesize experimental evidence on the anticancer effects of Lacticaseibacillus rhamnosus (L. rhamnosus) and its derivatives against colorectal cancer (CRC) cell models. Eligible studies investigated probiotics, postbiotics, or bioactive compounds derived from L. rhamnosus with an in vitro component; studies relying solely on in vivo animal models, clinical trials, or observational designs were excluded. PubMed and Scopus were searched to identify relevant studies. Risk of bias was assessed using a modified QUIN tool, and extracted data were tabulated. Owing to incomplete numerical data, meta-analysis was not feasible, and the results were synthesized accordingly. Seventeen studies were included. L. rhamnosus and its derivatives reduced CRC cell proliferation, induced apoptosis, and caused cell cycle arrest. Reported mechanisms included upregulation of Bax, caspase-3/9, and p53; downregulation of Bcl-2/Bcl-xl; inhibition of Wnt/β-catenin signaling; reduced invasion and migration; increased reactive oxygen species; and immunomodulatory effects. Key limitations were heterogeneity in interventions, dosages, exposure periods, and cell lines, along with incomplete reporting, which precluded quantitative synthesis. Overall, preclinical evidence indicates multimodal anticancer effects of L. rhamnosus in CRC models; however, standardized reporting and translational research are required. Full article

Background/Objectives: Long-term chronic intermittent hypobaric hypoxia (CIHH) is a common occupational exposure among high-altitude workers, particularly miners in northern Chile. This condition consists of working several days above 2500 m followed by rest at sea level, maintaining this cycle for years, which generates physiological alterations. This study analyzed associations among anthropometric indices and biomedical conditions in miners chronically exposed to long-term CIHH. Methods: This study was a cross-sectional analysis of 120 healthy Chilean male miners working at altitudes above 4400 m under a 7-day work/7-day rest schedule. Eligibility required ≥5 years of CIHH exposure and absence of cardiopulmonary disease, hypertension, diabetes, or oxygen therapy use. The assessments at altitude included oxygen saturation (SpO₂), blood pressure, heart rate, hematological parameters, metabolic parameters, and waist-to-hip ratio (WHR); measurements were obtained 18 h after arrival at altitude. WHR, BMI, SpO₂, and biomedical variables were collected following standardized procedures. Descriptive statistics and group comparisons were performed with Student’s t-test or the Wilcoxon test, with statistical significance set at p < 0.05. Normality assumption was assessed using the Shapiro–Wilk test. The association between WHR and SpO₂ was estimated using linear regression, with WHR scaled so that one unit corresponds to a 0.1-unit increase. Adjusted models included BMI, age, and years working under CIHH. Effect sizes and 95% confidence intervals (CIs) were reported. All statistical analyses were performed in the R programming language. Results: Mean SpO₂ was 89.07 ± 0.50% and mean WHR was 0.94 ± 0.01. In unadjusted comparisons, workers with WHR > 0.94 had lower SpO₂ than those below the threshold (88.8 ± 0.54 vs. 90.41 ± 0.50; p = 0.031). In adjusted models, the WHR–SpO₂ association was small and imprecise (β per 0.1-unit WHR = −0.67 pp; 95% CI −2.08 to 0.74). Hemoglobin showed an independent association with SpO₂, while other metabolic variables did not materially contribute. Conclusions: SpO₂ showed a modest inverse association with WHR in long-term CIHH workers. Even small saturation decreases may matter at high altitude. Combined WHR–SpO₂ monitoring may aid occupational surveillance, though longitudinal studies are needed to establish meaningful risk thresholds. Full article

Ginger supplementation is proposed as a natural ergogenic aid due to its anti-inflammatory and antioxidant properties, but its effects on endurance performance remain unclear. Methods: In this randomized, double-blind, placebo-controlled crossover trial, 30 trained cyclists (27 male, 3 females, aged 36 ± 11 yr) completed three visits: a baseline 75 km time trial, a post-supplementation time trial, and a second post-supplementation trial under the alternate condition. Participants consumed either ginger or placebo for four weeks. Statistics: Performance outcomes (i.e., 75 km time, VO₂, power output, heart rate, and RPE) were analyzed using repeated-measures ANOVA, with repeated-measures ANCOVA to assess dietary and age influences (p < 0.05). Results: Energy and carbohydrate intake were consistent across trials and unrelated to performance. Protein intake per kg body mass predicted performance time in the placebo trial and average VO₂ in the ginger trial; other macronutrients were not associated with outcomes. No significant differences were observed between ginger and placebo conditions for time to completion, VO₂, power output, heart rate, or perceived muscle soreness. Conclusions: Four weeks of ginger supplementation does not improve prolonged cycling performance, recovery, or muscle soreness in trained cyclists when dietary intake is controlled. Future research should explore cellular mechanisms to determine whether ginger supplementation could influence performance or recovery in endurance athletes. Full article

The results of most B3LYP and B3PW simulations, performed during the last quarter of century, dealing with ABO perovskite (001) surfaces, heterostructures, and oxygen vacancies therein, were reviewed. According to carried out B3LYP and B3PW simulations, almost all upper-layer atoms on the BO₂- and AO-terminated STO, BTO, PTO, CTO, SZO, BZO, PZO, and CZO perovskite (001) surfaces shift inwards. Practically all ABO perovskite second-layer atoms shift upwards. Finally, nearly all third-layer atoms, once more, shift inwards. The ABO perovskite (001) surface energies, for both BO₂ and AO terminations, are comparable. Computer simulations on the ABO perovskites indicate a significant rise of the B-O chemical bond covalency nearby the BO₂-terminated (001) surfaces in comparison to their bulk. B3LYP- and B3PW-simulated ABO perovskite bulk Γ-Γ band gaps are decreased nearby their BO₂- and AO-terminated (001) surfaces. We discuss recent B3PW simulations for the STO/BTO, STO/PTO, and SZO/PZO (001) heterostructures. Simulated optical band gaps of the STO/BTO, STO/PTO, and SZO/PZO (001) heterostructures mainly depend on the BO₂- or AO-terminations of the upper layer of the augmented film. The displacement magnitudes of the nearest neighbor atoms, around the (001) surface oxygen vacancy, in the ABO perovskites, usually, are larger than in their bulk. In the STO, BTO, PTO, and SZO perovskites, the electronic charge, ordinarily, is a lot better localized inside the bulk than the (001) surface oxygen vacancy. In the STO, BTO, PTO, and SZO perovskites, the (001) surface oxygen vacancy-induced defect levels are located closer to the conduction band bottom than in the bulk cases. Simulated formation energy difference between the bulk and the (001) surface oxygen vacancies in the STO, BTO, PTO, and SZO perovskites triggers the oxygen vacancy segregation from the bulk towards the (001) surface. All computer simulations for ABO perovskites were performed in their high-symmetry cubic phase. Full article

Humulus lupulus L. (hops), belonging to the Cannabaceae family, is grown mainly for brewing, with 98% of global production directed to this sector. Moreover, large volumes of female cone residues are generated as by-products, representing a valuable source of bioactive compounds that can be valorized under green chemistry principles. This study aimed to extract bioactive compounds from hop cone residues sourced from craft breweries using ultrasound-assisted (EH-UA) and microwave-assisted (EH-MA) extraction methods. Hydroalcoholic extracts (70%) were analyzed for chemical composition, antioxidant, antimicrobial, antiproliferative, nitric oxide (NO)-production inhibition, and photoprotective activities. GC-MS identified 32 compounds in EH-MA and 30 in EH-UA, including terpenes, sesquiterpenes, oxygenated sesquiterpenes, and fatty acids. Both extracts demonstrated strong antioxidant activity in cell-based (TBARS, OxHLIA) and chemical (DPPH, ABTS, FRAP) assays, particularly EH-MA. Significant antibacterial activity was observed, especially against Enterobacter cloacae, Pseudomonas aeruginosa, and Staphylococcus aureus (MIC 1–10 mg/mL), as well as antifungal activity against Aspergillus brasiliensis (MIC 2–2.5 mg/mL). Selective antiproliferative activity was observed against tumor cell lines Caco-2 and MCF-7 (GI₅₀ 25 μg/mL), without cytotoxicity toward nontumor cell lines Vero and PLP2 (GI₅₀ > 400 μg/mL). All extracts inhibited the production of the inflammation mediator NO, with EH-MA showing the most potent effect (IC₅₀ of 35 μg/mL), followed by EH-UA (IC₅₀ of 55 μg/mL). Photoprotective potential was also demonstrated, with SPF values of 19 (EH-MA) and 18 (EH-UA). In conclusion, hop cone residues can yield multifunctional extracts with antioxidant, antimicrobial, antiproliferative, anti-inflammatory, and photoprotective activities, which support their sustainable upcycling for pharmacological, nutraceutical, and cosmetic applications. Full article

Biogeochemical processes, including the oxygen cycle, were investigated in Lake Baikal during the spring thermal bar using a coupled numerical model that takes into account the intraday variability of atmospheric parameters and contains the following variables: nitrate, ammonium, phosphate, oxygen, chlorophyll a, phytoplankton, zooplankton, and small and large detritus. Nitrification, photosynthesis, remineralization, and respiration processes describe the biochemical dynamics of oxygen in the model. As a study area, the deep-water cross-section of Lake Baikal, Boldakov River–Maloye More Strait, was considered using meteorological data for June 2024 at the lake surface. Numerical results show that the thermal bar can contribute to the transport of dissolved oxygen and phyto- and zooplankton to the deeper layers of the lake. Full article

Background: Simplified field tests have gained increasing interest for the assessment of functional capacity in patients with post-COVID-19 condition; however, direct comparisons of functional performance and physiological responses between the 1-min sit-to-stand test (1MSTST) and the 6-min walk test (6MWT) remain limited. This study aimed to examine the associations between the two tests by evaluating functional performance, cardiopulmonary responses, oxygen desaturation, perceived exertion, and peripheral muscle strength. Furthermore, we explored whether the 1MSTST can be used as a complementary assessment, particularly within telerehabilitation pathways and in contexts where resource-intensive testing is not feasible. Methods: We conducted a cross-sectional observational study of adults recovering from moderate to severe COVID-19 between May and July 2021. Participants performed both the 1MSTST and 6MWT on the same day. Functional performance, peak heart rate, nadir peripheral oxygen saturation (SpO₂), perceived exertion, and handgrip dynamometry were recorded. Associations between test performances were assessed using correlation and partial correlation analyses, including adjustment for peripheral muscle strength. Results: Fifty-four patients were included. A moderate correlation was observed between 1MSTST repetitions and 6MWT distance (Spearman’s ρ = 0.47, p < 0.001), which was attenuated after adjustment for muscle strength and demographic variables. Peak heart rate and nadir SpO₂ responses were strongly correlated between tests (r = 0.75 and ρ = 0.83, respectively; both p < 0.001), with no significant differences in magnitude. Exercise-induced oxygen desaturation (≥4% SpO₂ drop) occurred at similar frequencies during both tests. Perceived exertion increased similarly following the 1MSTST and the 6MWT. Conclusions: In post-COVID-19 patients, the 1 min sit-to-stand test shows moderate concordance with the 6 min walk test for functional performance and strong agreement in cardiopulmonary responses. These findings suggest that the two tests assess overlapping but distinct aspects of functional capacity. This supports the use of the 1MSTST as a pragmatic complementary assessment when standard walking tests are not feasible, particularly within telerehabilitation pathways, primary care, and resource-limited settings. Full article

Emergent tracheal intubation in critically ill patients is a common, yet high-risk, intervention. It is frequently complicated by peri-intubation hypoxemia, hemodynamic instability, and metabolic derangements that increase the risk of arrhythmias, hypotension, cardiac arrest, and death. Because the highest-risk interval often occurs in the minutes surrounding induction, when apnea, derecruitment, and abrupt cardiopulmonary shifts converge, oxygenation failure frequently reflects a mismatch between preoxygenation strategy and the underlying physiology rather than inadequate oxygen delivery alone. This review proposes a phenotype-based approach to peri-intubation oxygenation and focuses on four high-risk phenotypes in whom standard preoxygenation strategies commonly fail: obesity, neuromuscular disease, right ventricular dysfunction or pulmonary hypertension, and post-operative respiratory failure with altered respiratory mechanics or airway anatomy. We summarize the key mechanisms that shorten safe apnea time, including reduced functional residual capacity, intrapulmonary shunt, elevated oxygen consumption, rapid derecruitment after induction, and impaired oxygenation–hemodynamics coupling. We then compare preoxygenation modalities as physiologic tools, including facemask oxygen, high-flow nasal cannula (HFNC), noninvasive ventilation (NIV), and controlled bag-mask ventilation (BMV), and integrate contemporary randomized trial evidence that informs bedside selection and combination of these approaches. Finally, we synthesize these concepts into a practical, physiology-informed framework to guide clinicians in choosing and troubleshooting preoxygenation strategies in high-risk patients undergoing emergent intubation. Full article

Objective: Based on previous findings on the Lingguizhugan (LGZG)-mediated gut–liver axis, this study clarifies the therapeutic mechanisms of LGZG in metabolic dysfunction-associated steatotic liver disease (MASLD), with a focus on the gut microbiota–bile acid–TGR5 (GPBAR1) axis. Methods: C57BL/6J mice were fed a high-fat diet (HFD) for 8 weeks to induce MASLD, followed by 4-week LGZG intervention (21.57 g/kg/day, oral gavage). Metabolic phenotypes, gut microbiota (16S rRNA sequencing), serum/hepatic bile acids (targeted metabolomics), and molecular targets (qPCR/Western blot) were analyzed. Results: LGZG significantly alleviated HFD-induced obesity, insulin resistance, and hepatic steatosis, while enhancing whole-body energy expenditure (increased oxygen consumption (VO₂), and heat production (p < 0.05). It also reduced serum ALT (p < 0.001) and AST levels (p < 0.01). Mechanistically, LGZG remodeled the gut microbiota, specifically increasing Akkermansia, Bifidobacterium and Lachnospiraceae_NK4A236_group while decreasing Lactobacillus. This shift inhibited the intestinal FXR-Fgf15 axis, concurrently activating the hepatic alternative bile acid synthesis pathway (upregulating CYP27A1 and CYP7B1 protein expression; p < 0.001 and p < 0.01, respectively). Consequently, systemic accumulation of non-12α-hydroxylated bile acids (non-12-OH BAs) such as hyocholic acid (HCA) and 7-ketolithocholic acid (7-ketoLCA) occurred—known TGR5 agonists and intestinal FXR antagonists. These changes elevated serum GLP-1 levels (p < 0.05) and activated adipose TGR5-cAMP/PKA/CREB signaling. The metabolic benefits primarily originated from non-12-OH BAs enrichment and TGR5-mediated adipose browning, not hepatic FXR activation. Conclusions: Our findings show that LGZG ameliorates MASLD by remodeling bile acid profiles via intestinal FXR-Fgf15 axis inhibition and hepatic alternative synthesis pathway activation. This study highlights the TGR5-targeting properties of LGZG, providing a mechanistic basis for its therapeutic use in metabolic disorders. Full article

Background: The combination of photodynamic therapy (PDT) and immunotherapy has been explored as an innovative approach to enhance efficacy against tumors. However, PDT shows limited effectiveness in treating deep-seated tumors, as light and lasers do not sufficiently penetrate tissue. Methods: Herein, we introduced a nanocarrier (NP_VR) via self-assembly, using an amphiphilic copolymer to co-deliver the hydrophobic photosensitizer verteporfin (VP) and the immunoadjuvant imiquimod (R837). Results: Our X-ray-induced photodynamic therapy (X-PDT) mechanism induced NP_VR to generate a large amount of cytotoxic reactive oxygen species (ROS), which directly killed cancer cells. Moreover, the released R837 facilitated immunogenic cell death following the X-PDT process and promoted the maturation of dendritic cells (DCs), thereby eliciting immune responses against malignant triple-negative breast cancer (TNBC). In animal experiments, the combined therapy using NP_VR showed a tumor growth inhibition rate of ~70%. Conclusions: This novel strategy opens new avenues to designing next-generation nanomedicines for use in immunotherapy and other combination therapies. Full article

Abiotic stresses severely constrain crop productivity by disrupting cellular redox homeostasis and hormone signaling. Although individual stresses differ in origin, plant responses converge on a conserved regulatory system centered on reactive oxygen species (ROS) and phytohormone crosstalk. Controlled ROS production in chloroplasts, mitochondria and the apoplast functions as a signaling mechanism that interacts dynamically with abscisic acid, auxin, ethylene, jasmonate and cytokinin pathways through shared regulatory nodes, including nicotinamide adenine dinucleotide phosphate (NADPH) oxidases and redox-sensitive transcriptional cascades. Endogenous metabolites, including phenolics, terpenoids, carotenoids, alkaloids, polyamines, glutathione and signaling peptides, are embedded within this network and modulate its amplitude and sensitivity. In parallel, non-microbial biostimulants derived from seaweeds, higher plants, protein hydrolysates and humic substances have been widely reported to enhance crop performance under abiotic stress. However, mechanistic integration between biostimulant research and plant stress signaling remains limited. In this review, we propose that terrestrial plant- and algal-derived biostimulants act not as external substitutes for hormones or antioxidants but as modulators of endogenous ROS–hormone signaling hubs. We first synthesize the current understanding of redox–hormone integration under abiotic stress, then examine endogenous metabolites as intrinsic regulators of this network, followed by an analysis of biostimulants in relation to shared regulatory nodes. By positioning biostimulant action within the established redox–hormone network, we provide a mechanistic framework that links stress biology with agronomic application and supports rational strategies to enhance crop resilience. Full article

The present theoretical study proposes and unravels chemical graft modification using a novel voltage stabilizer (3-amino-5-chlorophenyl 3-fluorophenyl methanone, ACFM) to ameliorate electrical insulation performance, oxygen-resistant characteristics, and thermal stability of addition-cure silicone rubber (SiR) used for cable accessory insulation in power transmission systems. First-principles calculations demonstrate that chemically grafted ACFM introduces shallow hole and electron traps into addition-cure SiR macromolecules to respectively impede hole transport and restrict hot electron production. Through molecular dynamics and Monte Carlo simulation, the chemically grafted ACFM is verified to enhance chain segment coalescence and decrease oxygen compatibility of addition-cure SiR macromolecules due to its higher dipole moment, leading to a reduction in oxygen permeation and improvement in thermal stability of the SiR crosslinked material. It is indicated from first-principles oxidation reaction paths that chemical grafting ACFM contributes positively to the oxidative stability of addition-cure SiR. The improved abilities of charge trapping and withstanding high temperatures together with enhanced resistance to both oxygen infiltration and oxidation of the addition-cure SiR material, as unraveled on a molecular scale in this research, open an avenue for developing advanced polymer dielectrics applied in harsh environments. Full article