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1.
Integr Zool ; 2024 Jun 19.
Article En | MEDLINE | ID: mdl-38897980

Intertidal organisms usually live near their upper thermal limits, and are vulnerable to future global warming. As a vital response to thermal stress, thermoregulatory strategy in physiological and behavioral performance is essential for organisms coping with thermal stress and surviving the changing world. To investigate the relationship between the thermoregulatory strategy and habitat temperature, in the present study, we comparatively investigated the thermal responsive strategy among different geographic populations of the supralittoral snail Littoraria sinensis by determining snails' cardiac function and behavioral performance. Our results indicated that populations inhabiting high ambient temperatures had higher sublethal temperatures (i.e. Arrhenius breakpoint temperatures, ABTs, the temperature at which the heart rate shapely decreases with further heating) and lethal temperatures (i.e. Flatline temperatures, FLTs, the temperature at which heart rate ceases), and behaved less actively (e.g. shorter moving distances and shorter moving time) in the face of high and rising temperatures-a physiological fight strategy. On the other hand, populations at relatively low ambient temperatures had relatively lower physiological upper thermal limits with lower ABTs and FLTs and moved more actively in the face of high and rising temperatures-a behavioral flight strategy. These results demonstrate that the thermoregulatory strategies of the snails are closely related to their habitat temperatures and are different among populations surviving divergent thermal environments.

2.
J Control Release ; 371: 484-497, 2024 Jun 11.
Article En | MEDLINE | ID: mdl-38851537

The precise and targeted delivery of therapeutic agents to the lesion sites remains a major challenge in treating brain diseases represented by ischemic stroke. Herein, we modified liposomes with mesenchymal stem cells (MSC) membrane to construct biomimetic liposomes, termed MSCsome. MSCsome (115.99 ± 4.03 nm) exhibited concentrated accumulation in the cerebral infarcted hemisphere of mice with cerebral ischemia-reperfusion injury, while showing uniform distribution in the two cerebral hemispheres of normal mice. Moreover, MSCsome exhibited high colocalization with damaged nerve cells in the infarcted hemisphere, highlighting its advantageous precise targeting capabilities over liposomes at both the tissue and cellular levels. Leveraging its superior targeting properties, MSCsome effectively delivered Dl-3-n-butylphthalide (NBP) to the injured hemisphere, making a single-dose (15 mg/kg) intravenous injection of NBP-encapsulated MSCsome facilitate the recovery of motor functions in model mice by improving the damaged microenvironment and suppressing neuroinflammation. This study underscores that the modification of the MSC membrane notably enhances the capacity of liposomes for precisely targeting the injured hemisphere, which is particularly crucial in treating cerebral ischemia-reperfusion injury.

3.
BMC Ophthalmol ; 24(1): 248, 2024 Jun 11.
Article En | MEDLINE | ID: mdl-38862946

BACKGROUND: Ahmed valve implantation demonstrated an increasing proportion in glaucoma surgery, but predicting the successful maintenance of target intraocular pressure remains a challenging task. This study aimed to evaluate the performance of machine learning (ML) in predicting surgical outcomes after Ahmed valve implantation and to assess potential risk factors associated with surgical failure to contribute to improving the success rate. METHODS: This study used preoperative data of patients who underwent Ahmed valve implantation from 2017 to 2021 at Ajou University Hospital. These datasets included demographic and ophthalmic parameters (dataset A), systemic medical records excluding psychiatric records (dataset B), and psychiatric medications (dataset C). Logistic regression, extreme gradient boosting (XGBoost), and support vector machines were first evaluated using only dataset A. The algorithm with the best performance was selected based on the area under the receiver operating characteristics curve (AUROC). Finally, three additional prediction models were developed using the best performance algorithm, incorporating combinations of multiple datasets to predict surgical outcomes at 1 year. RESULTS: Among 153 eyes of 133 patients, 131 (85.6%) and 22 (14.4%) eyes were categorized as the success and failure groups, respectively. The XGBoost was shown as the best-performance model with an AUROC value of 0.684, using only dataset A. The final three further prediction models were developed based on the combination of multiple datasets using the XGBoost model. All datasets combinations demonstrated the best performances in terms of AUROC (dataset A + B: 0.782; A + C: 0.773; A + B + C: 0.801). Furthermore, advancing age was a risk factor associated with a higher surgical failure incidence. CONCLUSIONS: ML provides some predictive value in predicting the outcomes of Ahmed valve implantation at 1 year. ML evaluation revealed advancing age as a common risk factor for surgical failure.


Glaucoma Drainage Implants , Glaucoma , Intraocular Pressure , Machine Learning , Humans , Female , Male , Glaucoma/surgery , Glaucoma/physiopathology , Intraocular Pressure/physiology , Middle Aged , Aged , Retrospective Studies , ROC Curve , Adult , Prosthesis Implantation/methods , Risk Factors , Visual Acuity/physiology , Treatment Outcome , Aged, 80 and over
4.
Nano Lett ; 2024 Jun 14.
Article En | MEDLINE | ID: mdl-38874568

Blood-contacting medical devices (BCDs) require antithrombotic, antibacterial, and low-friction surfaces. Incorporating a nanostructured surface with the functional hydrogel onto BCD surfaces can enhance the performances; however, their fabrication remains challenging. Here, we introduce a straightforward method to fabricate a multifunctional hydrogel-based nanostructure on BCD surfaces using O-carboxymethyl chitosan-based short nanofibers (CMC-SNFs). CMC-SNFs, fabricated via electrospinning and cutting processes, are easily sprayed and entangled onto the BCD surface. The deposited CMC-SNFs form a robust nanoweb layer via fusion at the contact area of the nanofiber interfaces. The superhydrophilic CMS-SNF nanoweb surface creates a water-bound layer that effectively prevents the nonspecific adhesion of bacteria and blood cells, thereby enhancing both antimicrobial and antithrombotic performances. Furthermore, the CMC-SNF nanoweb exhibits excellent lubricity and durability on the bovine aorta. The demonstration results of the CMC-SNF coating on catheters and sheaths provide evidence of its capability to apply multifunctional surfaces simply for diverse BCDs.

5.
Biomaterials ; 310: 122633, 2024 Oct.
Article En | MEDLINE | ID: mdl-38810387

Reactive oxygen species (ROS) that are overproduced in certain tumors can be considered an indicator of oxidative stress levels in the tissue. Here, we report a magnetic resonance imaging (MRI)-based probe capable of detecting ROS levels in the tumor microenvironment (TME) using ROS-responsive manganese ion (Mn2+)-chelated, biotinylated bilirubin nanoparticles (Mn@bt-BRNPs). These nanoparticles are disrupted in the presence of ROS, resulting in the release of free Mn2+, which induces T1-weighted MRI signal enhancement. Mn@BRNPs show more rapid and greater MRI signal enhancement in high ROS-producing A549 lung carcinoma cells compared with low ROS-producing DU145 prostate cancer cells. A pseudo three-compartment model devised for the ROS-reactive MRI probe enables mapping of the distribution and concentration of ROS within the tumor. Furthermore, doxorubicin-loaded, cancer-targeting ligand biotin-conjugated Dox/Mn@bt-BRNPs show considerable accumulation in A549 tumors and also effectively inhibit tumor growth without causing body weight loss, suggesting their usefulness as a new theranostic agent. Collectively, these findings suggest that Mn@bt-BRNPs could be used as an imaging probe capable of detecting ROS levels and monitoring drug delivery in the TME with potential applicability to other inflammatory diseases.


Doxorubicin , Drug Delivery Systems , Magnetic Resonance Imaging , Reactive Oxygen Species , Tumor Microenvironment , Tumor Microenvironment/drug effects , Humans , Reactive Oxygen Species/metabolism , Animals , Doxorubicin/pharmacology , Doxorubicin/administration & dosage , Doxorubicin/therapeutic use , Magnetic Resonance Imaging/methods , Drug Delivery Systems/methods , Nanoparticles/chemistry , Manganese/chemistry , Cell Line, Tumor , A549 Cells , Mice , Mice, Nude , Male , Mice, Inbred BALB C
6.
Trials ; 25(1): 326, 2024 May 17.
Article En | MEDLINE | ID: mdl-38755688

BACKGROUND: Post-acute sequelae of SARS-CoV-2 infection (PASC) symptoms have broad impact, and may affect individuals regardless of COVID-19 severity, socioeconomic status, race, ethnicity, or age. A prominent PASC symptom is cognitive dysfunction, colloquially referred to as "brain fog" and characterized by declines in short-term memory, attention, and concentration. Cognitive dysfunction can severely impair quality of life by impairing daily functional skills and preventing timely return to work. METHODS: RECOVER-NEURO is a prospective, multi-center, multi-arm, phase 2, randomized, active-comparator design investigating 3 interventions: (1) BrainHQ is an interactive, online cognitive training program; (2) PASC-Cognitive Recovery is a cognitive rehabilitation program specifically designed to target frequently reported challenges among individuals with brain fog; (3) transcranial direct current stimulation (tDCS) is a noninvasive form of mild electrical brain stimulation. The interventions will be combined to establish 5 arms: (1) BrainHQ; (2) BrainHQ + PASC-Cognitive Recovery; (3) BrainHQ + tDCS-active; (4) BrainHQ + tDCS-sham; and (5) Active Comparator. The interventions will occur for 10 weeks. Assessments will be completed at baseline and at the end of intervention and will include cognitive testing and patient-reported surveys. All study activities can be delivered in Spanish and English. DISCUSSION: This study is designed to test whether cognitive dysfunction symptoms can be alleviated by the use of pragmatic and established interventions with different mechanisms of action and with prior evidence of improving cognitive function in patients with neurocognitive disorder. If successful, results will provide beneficial treatments for PASC-related cognitive dysfunction. TRIAL REGISTRATION: ClinicalTrials.gov NCT05965739. Registered on July 25, 2023.


COVID-19 , Clinical Trials, Phase II as Topic , Cognitive Dysfunction , Multicenter Studies as Topic , SARS-CoV-2 , Humans , COVID-19/complications , Cognitive Dysfunction/therapy , Cognitive Dysfunction/psychology , Cognitive Dysfunction/diagnosis , Prospective Studies , Post-Acute COVID-19 Syndrome , Randomized Controlled Trials as Topic , Transcranial Direct Current Stimulation , Cognition , Treatment Outcome , Cognitive Behavioral Therapy/methods , Quality of Life
8.
Front Pharmacol ; 15: 1370915, 2024.
Article En | MEDLINE | ID: mdl-38783941

Objective: The price of pharmaceuticals is important from the economic and industrial perspectives but as well as patients' access to treatment. This study aimed to analyze the variables affecting the prices of new drugs in South Korea's pricing system. Methods: Data on 192 new drugs listed in South Korea from 2012 to 2022 were collected from the official website of the Health Insurance Review and Assessment Service. The independent variables included drugs for severe diseases, alternatives, number of patients, number of advanced 7 countries listed, budget impact, and listing period. The dependent variables included annual treatment cost and the price ratio to the advanced 7 country's average adjusted price. Descriptive statistics of variables, linear correlations between quantitative independent and dependent variables, and associations between independent and dependent variables were analyzed. Results: The mean annual treatment cost and price ratio to the advanced 7 country's average adjusted price were higher for drugs for severe diseases and those with no alternatives. Annual treatment cost and price ratio to the advanced 7 country's average adjusted price were negatively correlated with the number of patients and positively correlated with the number of advanced 7 countries listed. Annual treatment cost was affected by the variables drugs for severe diseases, alternatives, number of patients, number of advanced 7 countries listed, and budget impact. The price ratio to the advanced 7 country's average adjusted price was affected by drugs for severe diseases, alternatives, and the number of patients. Conclusion: This study revealed the effect of different variables on the prices of new drugs in South Korea, allowing for the development of a more effective assessment system to evaluate the prices of new drugs while ensuring profitability for pharmaceutical companies, sustainability of public insurance, and accessibility to drugs by patients.

10.
Article En | MEDLINE | ID: mdl-38814764

Positron emission tomography/magnetic resonance imaging (PET/MRI) systems can provide precise anatomical and functional information with exceptional sensitivity and accuracy for neurological disorder detection. Nevertheless, the radiation exposure risks and economic costs of radiopharmaceuticals may pose significant burdens on patients. To mitigate image quality degradation during low-dose PET imaging, we proposed a novel 3D network equipped with a spatial brain transform (SBF) module for low-dose whole-brain PET and MR images to synthesize high-quality PET images. The FreeSurfer toolkit was applied to derive the spatial brain anatomical alignment information, which was then fused with low-dose PET and MR features through the SBF module. Moreover, several deep learning methods were employed as comparison measures to evaluate the model performance, with the peak signal-to-noise ratio (PSNR), structural similarity (SSIM) and Pearson correlation coefficient (PCC) serving as quantitative metrics. Both the visual results and quantitative results illustrated the effectiveness of our approach. The obtained PSNR and SSIM were 41.96 ±4.91 dB (p<0.01) and 0.9654 ±0.0215 (p<0.01), which achieved a 19% and 20% improvement, respectively, compared to the original low-dose brain PET images. The volume of interest (VOI) analysis of brain regions such as the left thalamus (PCC = 0.959) also showed that the proposed method could achieve a more accurate standardized uptake value (SUV) distribution while preserving the details of brain structures. In future works, we hope to apply our method to other multimodal systems, such as PET/CT, to assist clinical brain disease diagnosis and treatment.

11.
Clin Trials ; : 17407745241244801, 2024 May 17.
Article En | MEDLINE | ID: mdl-38760932

BACKGROUND: The coronavirus disease 2019 pandemic highlighted the need to conduct efficient randomized clinical trials with interim monitoring guidelines for efficacy and futility. Several randomized coronavirus disease 2019 trials, including the Multiplatform Randomized Clinical Trial (mpRCT), used Bayesian guidelines with the belief that they would lead to quicker efficacy or futility decisions than traditional "frequentist" guidelines, such as spending functions and conditional power. We explore this belief using an intuitive interpretation of Bayesian methods as translating prior opinion about the treatment effect into imaginary prior data. These imaginary observations are then combined with actual observations from the trial to make conclusions. Using this approach, we show that the Bayesian efficacy boundary used in mpRCT is actually quite similar to the frequentist Pocock boundary. METHODS: The mpRCT's efficacy monitoring guideline considered stopping if, given the observed data, there was greater than 99% probability that the treatment was effective (odds ratio greater than 1). The mpRCT's futility monitoring guideline considered stopping if, given the observed data, there was greater than 95% probability that the treatment was less than 20% effective (odds ratio less than 1.2). The mpRCT used a normal prior distribution that can be thought of as supplementing the actual patients' data with imaginary patients' data. We explore the effects of varying probability thresholds and the prior-to-actual patient ratio in the mpRCT and compare the resulting Bayesian efficacy monitoring guidelines to the well-known frequentist Pocock and O'Brien-Fleming efficacy guidelines. We also contrast Bayesian futility guidelines with a more traditional 20% conditional power futility guideline. RESULTS: A Bayesian efficacy and futility monitoring boundary using a neutral, weakly informative prior distribution and a fixed probability threshold at all interim analyses is more aggressive than the commonly used O'Brien-Fleming efficacy boundary coupled with a 20% conditional power threshold for futility. The trade-off is that more aggressive boundaries tend to stop trials earlier, but incur a loss of power. Interestingly, the Bayesian efficacy boundary with 99% probability threshold is very similar to the classic Pocock efficacy boundary. CONCLUSIONS: In a pandemic where quickly weeding out ineffective treatments and identifying effective treatments is paramount, aggressive monitoring may be preferred to conservative approaches, such as the O'Brien-Fleming boundary. This can be accomplished with either Bayesian or frequentist methods.

12.
Case Reports Plast Surg Hand Surg ; 11(1): 2351130, 2024.
Article En | MEDLINE | ID: mdl-38751547

Carpal tunnel syndrome is the most common entrapment neuropathy in the upper extremity. Palmaris longus, flexor digitorum superficialis, and lumbricals have infrequently been reported as causes of nerve compression. During routine Korean cadaver dissection, we incidentally identified an anatomic variant of first lumbrical muscle within the carpal tunnel in both wrists. The aberrant musculature originated from the radial side of the second FDS muscle at distal forearm level, running separately across the wrist beneath the flexor retinaculum. The dissected anomalous muscle was identified as an additional muscle belly of the first lumbrical muscle. Compression of the median nerve at the wrist might rarely be caused by the presence of such a tendon or muscle anomaly found in this study. Surgeons should be aware of possible anatomic variations in the carpal tunnel, and be prepared to modify their surgical plan accordingly.

13.
World J Psychiatry ; 14(5): 686-694, 2024 May 19.
Article En | MEDLINE | ID: mdl-38808082

BACKGROUND: Insomnia is among the most common sleep disorders worldwide. Insomnia in older adults is a social and public health problem. Insomnia affects the physical and mental health of elderly hospitalized patients and can aggravate or induce physical illnesses. Understanding subjective feelings and providing reasonable and standardized care for elderly hospitalized patients with insomnia are urgent issues. AIM: To explore the differences in self-reported outcomes associated with insomnia among elderly hospitalized patients. METHODS: One hundred patients admitted to the geriatric unit of our hospital between June 2021 and December 2021 were included in this study. Self-reported symptoms were assessed using the Athens Insomnia Scale (AIS), Generalized Anxiety Disorder Scale-7 (GAD-7), Geriatric Depression Scale-15 (GDS-15), Memorial University of Newfoundland Scale of Happiness (MUNSH), Barthel Index Evaluation (BI), Morse Fall Scale (MFS), Mini-Mental State Examination, and the Short Form 36 Health Survey Questionnaire (SF-36). Correlation coefficients were used to analyze the correlation between sleep quality and self-reported symptoms. Effects of insomnia was analyzed using Logistic regression analysis. RESULTS: Nineteen patients with AIS ≥ 6 were included in the insomnia group, and the incidence of insomnia was 19% (19/100). The remaining 81 patients were assigned to the non-insomnia group. There were significant differences between the two groups in the GDA-7, GDS-15, MUNSH, BI, MFS, and SF-36 items (P < 0.05). Patients in the insomnia group were more likely to experience anxiety, depression, and other mental illnesses, as well as difficulties with everyday tasks and a greater risk of falling (P < 0.05). Subjective well-being and quality of life were poorer in the insomnia group than in the control group. The AIS scores positively correlated with the GAD-7, GDS-15, and MFS scores in elderly hospitalized patients with insomnia (P < 0.05). Logistic regression analysis showed that GDS-15 ≥ 5 was an independent risk factor for insomnia in elderly hospitalized patients (P < 0.05). CONCLUSION: The number of self-reported symptoms was higher among elderly hospitalized patients with insomnia. Therefore, we should focus on the main complaints of patients to meet their care needs.

14.
Eur J Heart Fail ; 2024 May 15.
Article En | MEDLINE | ID: mdl-38745502

AIM: The TRANSFORM-HF trial demonstrated no significant outcome differences between torsemide and furosemide following hospitalization for heart failure (HF), but may have been impacted by non-adherence to the randomized diuretic. The current study sought to determine the treatment effect of torsemide versus furosemide using an on-treatment analysis inclusive of all randomized patients except those confirmed non-adherent to study diuretic. METHODS AND RESULTS: TRANSFORM-HF was an open-label, pragmatic randomized trial of 2859 patients hospitalized for HF from June 2018 through March 2022. Patients were randomized to a loop diuretic strategy of torsemide versus furosemide with investigator-selected dosage. This post-hoc on-treatment analysis included all patients alive with either known or unknown diuretic status, and excluded patients confirmed to be non-adherent to study diuretic. This modified on-treatment definition was applied separately at time of hospital discharge and 30-day follow-up. All-cause mortality and hospitalization outcomes were assessed over 12 months. Overall, 2570 (89.9%) and 2374 (83.0%) patients were included in on-treatment analyses at discharge and 30-day follow-up, respectively. There was no significant difference in all-cause mortality between torsemide and furosemide in patients on-treatment at discharge (17.5% vs. 17.8%; hazard ratio [HR] 1.01 [95% confidence interval [CI] 0.83-1.22], p = 0.96) and at 30-day follow-up (14.5% vs. 15.0%; HR 1.02 [95% CI 0.81-1.27], p = 0.90). All-cause mortality or all-cause hospitalization was similar between torsemide and furosemide in patients who were on-treatment at discharge (58.3% vs. 61.3%; HR 0.92 [95% CI 0.82-1.03]) and 30-day follow-up (60.9% vs. 64.4%; HR 0.93 [95% CI 0.82-1.05]). In patients who were on-treatment at 30-day follow-up, there were 677 total hospitalizations in the torsemide group and 686 total hospitalizations in the furosemide group (rate ratio 0.99 [95% CI 0.86-1.14], p = 0.87). CONCLUSIONS: In TRANSFORM-HF, a post-hoc on-treatment analysis did not meaningfully differ from the original trial results. Among those deemed compliant with the assigned diuretic, there remained no significant difference in mortality or hospitalization after HF hospitalization with a strategy of torsemide versus furosemide. CLINICAL TRAIL REGISTRATION: ClinicalTrials.gov Identifier: NCT03296813.

15.
Sci Rep ; 14(1): 10640, 2024 May 09.
Article En | MEDLINE | ID: mdl-38724519

Slide electrification is the spontaneous separation of electric charges at the rear of water drops sliding over solid surfaces. This study delves into how surfaces treated with a low-pressure plasma impact water slide electrification. Ar, O2, and N2 plasma treatment reduced the drop charge and contact angles on glass, quartz, and SU-8 coated with 1H,1H,2H,2H-perfluoroctyltrichlorosilane (PFOTS), and polystyrene. Conversely, 64% higher drop charge was achieved using electrode-facing treatment in plasma chamber. Based on the zeta potential, Kelvin potential, and XPS measurements, the plasma effects were attributed to alterations of the topmost layer's chemistry, such as oxidation and etching, and superficially charge deposition. The surface top layer charges were less negative after electrode-facing and more negative after bulk plasma treatment. As a result, the zeta potential was less negative after electrode-facing and more negative after bulk plasma treatment. Although the fluorinated layer was applied after plasma activation, we observed a discernible impact of plasma-glass treatment on drop charging. Plasma surface modification offers a means to adjust drop charges: electrode-facing treatment of the fluorinated layer leads to an enhanced drop charge, while plasma treatment on the substrate prior to fluorination diminishes drop charges, all without affecting contact angles or surface roughness.

16.
Mol Carcinog ; 63(7): 1288-1302, 2024 Jul.
Article En | MEDLINE | ID: mdl-38607237

Baicalein has been implicated in the chemotherapy overcoming triple-negative breast cancer (TNBC). However, many unanswered questions remain regarding its role in treating TNBC. Here, we sought to demonstrate the molecular pathway mediated by baicalein in TNBC. Lysine-specific demethylase 4E (KDM4E), reduced in TNBC cells, was identified as a target protein of baicalein, and baicalein enhanced the protein expression and stability of KDM4E in TNBC cells. Knockdown of KDM4E attenuated the inhibitory effect of baicalein on TNBC cell activity, as demonstrated by intensified mobility, viability, and apoptosis resistance in TNBC cells. KDM4E activated protein bicaudal D homolog 1 (BICD1) expression by reducing the deposition of histone H3 lysine 9 trimethylation (H3K9me3) in its promoter, whereas BICD1 promoted protease-activated receptor-1 (PAR1) endocytosis and blocked PAR1 signaling through physical interaction with PAR1. Knockdown of KDM4E strengthened the PAR1-dependent activity of TNBC cells in response to thrombin activation, whereas TNBC progression activated by PAR1 signaling was blocked by combined overexpression of BICD1. Taken together, our data indicate that baicalein-promoted KDM4E enhanced the expression of BICD1 and activated the inhibitory effect of BICD1 on PAR1 signaling, thereby inhibiting TNBC progression.


Flavanones , Signal Transduction , Triple Negative Breast Neoplasms , Humans , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Triple Negative Breast Neoplasms/genetics , Flavanones/pharmacology , Female , Signal Transduction/drug effects , Cell Line, Tumor , Animals , Receptor, PAR-1/metabolism , Receptor, PAR-1/genetics , Gene Expression Regulation, Neoplastic/drug effects , Cell Proliferation/drug effects , Apoptosis/drug effects , Disease Progression , Mice
17.
ACS Appl Mater Interfaces ; 16(19): 25519-25528, 2024 May 15.
Article En | MEDLINE | ID: mdl-38593204

This work investigates the coupling effect of structural lubrication and thermal excitation on phononic friction between black phosphorus (BP) layers. As the rotation angle increases from commensurate to incommensurate states, the friction gradually decreases at any temperature. However, the role of temperature in friction depends on commensurability. For a rotation angle less than 10°, increasing temperature leads to a decrease in friction due to thermal excitation. Conversely, when the rotation angle exceeds 10°, elevated temperature results in an increase in friction due to the effect of thermal collision. At a critical rotation angle of 10°, higher temperatures lead to reduced friction through thermal lubrication at low speeds, and at large speeds, the thermal excitation duration becomes so short that the role of thermal lubrication is weakened, and instead thermal collision dominates. Further research reveals that BP's ability to withstand different maximum speeds is also determined by commensurability. Finally, a method to measure the sliding period length of a rotated tip through an unrotated substrate potential energy topography is proposed and simply verified by using the phonon spectrum.

18.
Medicine (Baltimore) ; 103(14): e37678, 2024 Apr 05.
Article En | MEDLINE | ID: mdl-38579025

2-Deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography (PET)/computed tomography (CT) is known to be a helpful imaging modality for sacral chordoma, but its detailed characteristics have not been fully described. The purpose of our study was to identify the [18F]FDG PET/CT imaging characteristics of sacral chordoma and compare them with other sacral malignancy. This retrospective study included patients who underwent [18F]FDG PET/CT because of a mass involving the sacrum. Investigated visual findings included visual score and distribution, and semiquantitative parameters measured included standardized uptake values (SUVmax, SUVpeak, SUVmean), tumor-to-liver ratio (TLR), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and tumor size. Comparison studies and receiver operating characteristics (ROC) curve analysis were performed to differentiate between sacral chordoma and other sacral malignancy. Ten patients with sacral chordoma were finally included (M:F = 6:4, median age = 67 yr). On [18F]FDG PET/CT, sacral chordomas presented as a mass with minimal-moderate uptake with a usually heterogenous distribution. Compared with 12 patients with other sacral malignancies (M:F = 4:8, median age 42 yr), sacral chordoma showed a significantly lower TLR (median value 2.1 vs 6.3, P = .021). In ROC curve analysis, TLR showed the largest area under the curve (AUC) of 0.79 (cutoff ≤ 4.0; sensitivity 100.0%, specificity 58.3%; P = .004), and SUVmax showed the second largest AUC of 0.73 (cutoff ≤ 6.9; sensitivity 80.0%, specificity 66.7%; P = .034). [18F]FDG PET/CT of sacral chordoma showed minimal-moderate uptake. The TLR of [18F]FDG PET/CT was significantly lower than that of other sacral malignancy and was the most useful parameter for differentiating sacral chordoma, with the largest AUC. SUVmax could be another helpful semiquantitative parameter.


Chordoma , Positron Emission Tomography Computed Tomography , Humans , Aged , Adult , Positron Emission Tomography Computed Tomography/methods , Fluorodeoxyglucose F18 , Chordoma/diagnostic imaging , Diagnosis, Differential , Sacrum/diagnostic imaging , Retrospective Studies , Tumor Burden , Radiopharmaceuticals
19.
FASEB J ; 38(8): e23613, 2024 Apr 30.
Article En | MEDLINE | ID: mdl-38661048

The unpredictable survival rate of autologous fat grafting (AFG) seriously affects its clinical application. Improving the survival rate of AFG has become an unresolved issue in plastic surgery. Peroxisome proliferator-activated receptor-γ (PPAR-γ) regulates the adipogenic differentiation of adipocytes, but the functional mechanism in AFG remains unclear. In this study, we established an animal model of AFG and demonstrated the superior therapeutic effect of PPAR-γ regulation in the process of AFG. From day 3 after fat grafting, the PPAR-γ agonist rosiglitazone group consistently showed better adipose integrity, fewer oil cysts, and fibrosis. Massive macrophage infiltration was observed after 7 days. At the same time, M2 macrophages begin to appear. At day 14, M2 macrophages gradually became the dominant cell population, which suppressed inflammation and promoted revascularization and fat regeneration. In addition, transcriptome sequencing showed that the differentially expressed genes in the Rosiglitazone group were associated with the pathways of adipose regeneration, differentiation, and angiogenesis; these results provide new ideas for clinical treatment.


Adipose Tissue , Macrophages , PPAR gamma , Rosiglitazone , Transplantation, Autologous , Animals , PPAR gamma/metabolism , PPAR gamma/genetics , Macrophages/metabolism , Adipose Tissue/metabolism , Adipose Tissue/cytology , Rosiglitazone/pharmacology , Male , Cell Differentiation , Adipogenesis , Adipocytes/metabolism , Mice , Rats
20.
Nanotechnology ; 35(29)2024 Apr 30.
Article En | MEDLINE | ID: mdl-38593759

Herein, we employ molecular dynamics simulations to decode the friction properties and phonon energy dissipation between black phosphorus layers. The observations reveal the influence of three factors, temperature, velocity, and normal load, on the friction force of monolayer/bilayer black phosphorus. Specifically, friction is negatively correlated with layer thickness and temperature, and positively correlated with velocity and normal load. The change in friction force is further explained in terms of frictional energy dissipation, and supplemented by the height of potential barriers as well as the number of excited phonons. From the phonon spectrum analysis, the phonon number at the contact interface is found to be higher than that at the non-contact interface. This is due to the larger distance of the contact interface atoms deviate from their equilibrium positions, resulting in higher total energy generated by more intense oscillations, and therefore contributes greater to friction.

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