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In this paper, a mathematical ordinary differential tumor-immune model is proposed based on an immune checkpoint inhibitor, which is an innovative method for tumor immunotherapies. Two important factors in tumor-immune response are the programmed cell death protein 1 (PD-1) and its ligand PD-L1. The model consists of three populations: tumor cells, activated T cells and anti-PD-1. By analyzing the dynamics of the model, it is found that there is always a unique tumor-free equilibrium and at most two tumor interior equilibria. The nonexistence of nontrivial positive periodic orbits is established by using the new Dulac function, and then a global dynamics of the model is obtained. The conclusions of our analysis show that increasing the possibility of T cells killing tumor cells (p), early detection of tumor cells, or the use of PD-1 inhibitors to activate T cells are effective in eliminating tumor cells. [ABSTRACT FROM AUTHOR]

Objective: Population-based epidemiological data on left common iliac vein (LCIV) compression is scarce. This study aimed to investigate the prevalence of LCIV compression in an asymptomatic population and patients with left iliofemoral deep vein thrombosis (IF-DVT). Materials and Methods: Nonprobability sampling method was used in this multicenter cross-sectional study. The minimum diameter of LCIV and right common iliac vein minimum were measured. The percentage of LCIV compression (LCIV-CP) was calculated. Compression severity (CS) was classified as mild (CP ≤ 50%), moderate (50% < CP ≤ 70%), and severe (CP > 70%). Results: In all, 896 subjects constituted the asymptomatic population and 93 patients constituted the IF-DVT population. In the asymptomatic population, LCIV-CP ranged from 1.1% to 89.9% (mean 44.0%), and people with mild, moderate, and severe CS accounted for 62.3%, 28.2%, and 9.5%, respectively. In the IF-DVT population, the mean LCIV-CP was 71.1% (range 42.2%–95.2%), and patients with severe CS accounted for 75.3%. Gender and age differences in LCIV-CP and CS distribution were observed in the asymptomatic population. Females, the young- and middle-aged group had higher LCIV-CPs. In the population with moderate-severe CS, the middle-aged group accounted for a larger proportion. Middle-aged females comprised the highest percentage of patients with moderate or severe CS. Sex and age affected the LCIV-CP and CS distribution. No gender and age differences were observed in the IF-DVT population. Conclusions: LCIV compression is common in population. Middle-aged females are the predominant population with moderate-severe compression. Overlapping of LCIV-CP in the asymptomatic and IF-DVT population is significant and other risk factors should be integrated into the consideration when assessing the risk of IF-DVT secondary to LCIV compression. [ABSTRACT FROM AUTHOR]

Background: Observing and studying clinical efficacy and safety of apatinib mesylate tablet in the treatment of advanced malignant melanoma (MM). Methods: Retrospectively analyzing the clinical data of 22 patients with metastatic MM who had failed conventional chemotherapy from June 2016 to January 2018. All patients took 500 mg of apatinib mesylate tablets per day. The efficacy should be evaluated according to RECIST 1.1 criteria. Adverse events (AEs) should be graded according to NCI-CTCAE 4.0. Results: There were two cases of partial remission (PR), 11 of stable disease (SD) and nine of progressive disease (PD) in the 22 patients with advanced MM, where the objective remission rate (ORR) was 9.1% and the disease control rate (DCR) was 59.1%. The median progression-free survival (PFS) was 7.5 months, and the 6-month progression-free survival rate (PFR) was 54.7%. Six patients died and the overall survival (OS) was not reached. AEs were controllable and all were in Grade 1–3. Conclusion: Apatinib mesylate tablets have a certain curative effect on patients with malignant melanomas of Stage IV who failed conventional chemotherapy. Apatinib mesylate tablets at a daily dose of 500 mg are well tolerated by most patients. [ABSTRACT FROM AUTHOR]

Understanding the adsorption behavior of antibiotic molecules on minerals is crucial for determining the environmental fate and transport of antibiotics in soils and waters. However, the microscopic mechanisms that govern the adsorption of common antibiotics, such as the molecular orientation during the adsorption process and the conformation of sorbate species, are not well understood. To address this gap, we conducted a series of molecular dynamics (MD) simulations and thermodynamics analyses to investigate the adsorption of two typical antibiotics, tetracycline (TET) and sulfathiazole (ST), on the surface of montmorillonite. The simulation results indicated that the adsorption free energy ranged from − 23 to − 32 kJ·mol−1, and − 9 to − 18 kJ·mol−1 for TET and ST, respectively, which was consistent with the measured difference of sorption coefficient (K d) for TET-montmorillonite of 11.7 L·g−1 and ST-montmorillonite of 0.014 L·g−1. The simulations also found that TET was adsorbed through dimethylamino groups (85% in probability) with a molecular conformation vertical to the montmorillonite's surface, while ST was adsorbed through sulfonyl amide group (95% in probability) with vertical, tilted and parallel conformations on the surface. The results confirmed that molecular spatial orientations could affect the adsorption capacity between antibiotics and minerals. Overall, the microscopic adsorption mechanisms revealed in this study provide critical insights into the complexities of antibiotics adsorption to soil and facilitate the prediction of adsorption capacity of antibiotics on minerals and their environmental transport and fate. This study contributes to our understanding of the environmental impacts of antibiotic usage and highlights the importance of considering molecular-level processes when assessing the fate and transport of antibiotics in the environment. [Display omitted] • K d value of TET and ST with montmorillonite is 11.70 and 0.014 L·g−1, respectively. • The adsorption free energy of TET and ST is − 23 to − 32 and − 9 to − 18 kJ·mol−1. • TET is adsorbed through dimethylamino group and ST is sulfonyl amide group. • The adsorbed angle of TET is vertical with montmorillonite and tilted for ST. [ABSTRACT FROM AUTHOR]

A periodic pulse differential equation model of tumor immunotherapy is established by considering the periodic and transient behavior of infusing immune cells. Using comparison theorem and Floquet multiplier theory of the impulsive differential equation, the boundedness of the model solution, the existence and stability of the free-tumor periodic solution are given. Furthermore, the persistence of the system is analyzed. Numerical simulations are carried to confirm the main theorems. [ABSTRACT FROM AUTHOR]

Background: Many patients in the intensive care unit (ICU) suffer from post-traumatic stress disorder (PTSD), which seriously affects the treatment, recovery, and prognosis of patients., Objective: To observe the effect of empowerment psychological intervention on the status of PTSD in ICU patients., Methods: A total of 86 patients with PTSD who were treated in ICU from July 2019 to December 2021 were divided into two groups according to the intervention method. The control group (n = 43) used routine psychological intervention, while the intervention group (n = 43) used empowerment psychological intervention led by specialist nurses. The Pittsburgh Sleep Quality Index (PSQI) was used to assess the sleep quality of the patients. The Resilience Questionnaire (CD-RISC) was used to evaluate the resilience of the patients, and the Post Traumatic Stress Disorder Self-Rating Scale (PTSD-SS) was used to assess the severity of the symptoms. The Hamilton Anxiety and Depression Inventory (HAMA and HAMD) was adapted to assess the degree of anxiety and depression, and the Post-Traumatic Growth Inventory (PTGI) was adapted to evaluate the post-traumatic growth of the patients., Results: After the intervention, the total CD-RISC score and its tenacity, self-improvement, and optimism scores in the two groups were all higher than before, and the total PSQI score and its sleep quality, time, efficiency and impairment, as well as hypnotic drugs, daytime dysfunction and time to sleep were lower than before, and the CD-RISC score in the intervention group was higher than that in the control group, PSQI score was lower than that in the control group (p < 0.05). After the intervention, PTSD-SS scores and anxiety-depression scores were lower, and PTGI scores were higher in both groups than before (p < 0.05)., Conclusion: The empowerment psychological intervention led by specialist nurses applied to ICU patients with PTSD can improve their psychological resilience and sleep quality, reduce negative emotions, alleviate clinical symptoms, and promote post-traumatic growth.

An iterative approach between machine learning (ML) and laboratory experiments was developed to accelerate the design and synthesis of environmental catalysts (ECs) using selective catalytic reduction (SCR) of nitrogen oxides (NO x ) as an example. The main steps in the approach include training a ML model using the relevant data collected from the literature, screening candidate catalysts from the trained model, experimentally synthesizing and characterizing the candidates, updating the ML model by incorporating the new experimental results, and screening promising catalysts again with the updated model. This process is iterated with a goal to obtain an optimized catalyst. Using the iterative approach in this study, a novel SCR NO x catalyst with low cost, high activity, and a wide range of application temperatures was found and successfully synthesized after four iterations. The approach is general enough that it can be readily extended for screening and optimizing the design of other environmental catalysts and has strong implications for the discovery of other environmental materials.

Quantitative assessment of the responses of biofilm structure to external hydrodynamics is critical for understanding biofilm detachment mechanisms. This study used multidimensional imaging and numerical simulation approaches to elucidate the complex relationships between biofilm detachment and hydrodynamics with Shewanella oneidensis MR-1. By integrating real-time confocal laser scanning microscopy (CLSM) images with image analysis tools, the three-dimensional structural changes occurring in thin MR-1 biofilms (<10 μm) under hydrodynamic treatment at a flow velocity of 0.42 × 10 -3 to 3.3 × 10 -3 m/s in the laminar flow regime were visualized in situ and quantified with single-cell resolution. Analyses of the imaging results revealed high spatial heterogeneity in the degree and intensity of biofilm detachment. Spots with thick and rough biofilm surfaces or high flow rates had high detachment rates, indicating that local biofilm morphology, including thickness and roughness, and hydrodynamic flow conditions collectively controlled the detachment rate. Numerical simulations revealed a significant correlation between local detachment events and the shear stress induced by hydraulic flow at the three-dimensional level. Compared to the even or thin biofilm, a thick or rough structure might induce a 2-fold increase in shear stress over local biofilm surfaces at a microscale dimension. The results provide quantitative and microscopic insights into biofilm detachment processes in subsurface environments, especially in domains under dynamic flow conditions, such as those in hyporheic zones. The relationship between biofilm detachment and hydrodynamics and biofilm structural factors can be integrated into reactive transport models used to describe microbial growth and transport in porous media. IMPORTANCE Detachment is an important process determining the structure and function of bacterial biofilm, which has significant implications for biogeochemical cycling of elements, biofilm application, and infection control in clinical settings. Quantifying the responses of biofilm structure to hydrodynamics is crucial for understanding biofilm detachment mechanisms in aquatic environments. In this work, the spatial and temporal changes occurring in biofilm structures in response to different hydrodynamic conditions were studied by using flow cell reactors. We established the quantitative relationships among detachment, biofilm morphology, and shear stress induced by changes in hydrodynamic conditions. This work provides a quantitative understanding of the complex relationship between biofilm detachment and hydrodynamics in natural environments.

Background: The clinical efficacy and safety of Endostar combined with chemotherapy in the treatment of metastatic malignant melanoma (MM) were analyzed and the indicators capable of predicting the efficacy of the regimen were identified to guide clinical practice. Patients and methods: The clinical data of 55 patients with metastatic MM without gene mutations who were treated with Endostar combined with dacarbazine and cisplatin were retrospectively analyzed. Efficacy was assessed using RECIST 1.1, and adverse events (AEs) were graded according to NCI-CTCAE 4.0. The log-rank test was used to compare the survival curves of patients in different subgroups, and stepwise multivariate Cox regression analysis was used to determine significant prognostic factors. Differences were considered statistically significant at P <0.05. Results: Of the 55 patients, seven showed a partial response, 20 showed stable disease, and 28 showed progressive disease. The median progression-free survival was 17.9 months. AEs were controllable. Univariate analysis identified biotherapy, clinical stage, clinical classification, low baseline platelet count, platelet to albumin ratio (PAR), and platelet to globulin ratio (PGR) as factors affecting drug efficacy. Multivariate Cox regression analysis identified clinical stage and PAR as independent factors predicting the efficacy of the regimen. Conclusions: Endostar combined with chemotherapy showed a curative effect on metastatic MM without gene mutations, and AEs were controllable. The baseline platelet count and derived PAR and PGR values were associated with the efficacy of the regimen. The potential value of efficacy prediction remains to be further verified by prospective random experiments., Competing Interests: All authors declare that they have no competing interests in this work.

Sentinel lymph node biopsy (SLNB) is a sensitive operation for finding micro-metastasis in patients with cutaneous melanoma without evidence of clinically positive lymph node findings. However, until now, no clinical trials or retrospective studies with large samples have been performed to investigate the clinical role of SLNB for cutaneous melanoma patients. In this study, we used the data of cutaneous melanoma from the Surveillance, Epidemiology, and End Results (SEER) database to compare overall survival (OS) and melanoma-specific survival (MSS) outcomes with clinical lymph node and SLN status. In total, 56,285 eligible patients were identified in this study. Cutaneous melanoma patients with clinically-positive lymph nodes had significantly shorter OS (46.1% vs 78.6%, p = 0.000) and MSS (55.8% vs 90.5, p = 0.000) compared with clinically-negative lymph node patients. Patients who underwent SLNB had significantly longer 5-year rates for OS (84.3% vs 70.1, p = 0.000) and MSS (91.5% vs 90.3, p = 0.000) compared with patients who did not undergo SLNB (lymph node observation). Patients with a negative SLNB had a significantly longer 5-year rate for OS (86.5% vs 68.1% vs 46.1, p = 0.000) and MSS (93.7% vs 75.1% 55.8%, p = 0.000) than patients who were SLNB-positive or had clinically-positive lymph nodes. This present study showed that the status of SLN is a valuable prognostic factor in patients with Breslow thickness greater than 1 mm in clinically-negative lymph node cutaneous melanoma., Competing Interests: None of the authors have any conflicts of interest to declare.