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1.
PeerJ ; 12: e17166, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38563004

RESUMO

Objectives: To test the hypothesis that 'live high-base train high-interval train low' (HiHiLo) altitude training, compared to 'live low-train high' (LoHi), yields greater benefits on performance and physiological adaptations. Methods: Sixteen young male middle-distance runners (age, 17.0 ± 1.5 y; body mass, 58.8 ± 4.9 kg; body height, 176.3 ± 4.3 cm; training years, 3-5 y; training distance per week, 30-60 km.wk-1) with a peak oxygen uptake averaging ~65 ml.min-1.kg-1 trained in a normobaric hypoxia chamber (simulated altitude of ~2,500 m, monitored by heart rate ~170 bpm; thrice weekly) for 3 weeks. During this period, the HiHiLo group (n = 8) stayed in normobaric hypoxia (at ~2,800 m; 10 h.day-1), while the LoHi group (n = 8) resided near sea level. Before and immediately after the intervention, peak oxygen uptake and exercise-induced arterial hypoxemia responses (incremental cycle test) as well as running performance and time-domain heart rate variability (5-km time trial) were assessed. Hematological variables were monitored at baseline and on days 1, 7, 14 and 21 during the intervention. Results: Peak oxygen uptake and running performance did not differ before and after the intervention in either group (all P > 0.05). Exercise-induced arterial hypoxemia responses, measured both at submaximal (240 W) and maximal loads during the incremental test, and log-transformed root mean square of successive R-R intervals during the 4-min post-run recovery period, did not change (all P > 0.05). Hematocrit, mean reticulocyte absolute count and reticulocyte percentage increased above baseline levels on day 21 of the intervention (all P < 0.001), irrespective of group. Conclusions: Well-trained runners undertaking base training at moderate simulated altitude for 3 weeks, with or without hypoxic residence, showed no performance improvement, also with unchanged time-domain heart rate variability and exercise-induced arterial hypoxemia responses.


Assuntos
Altitude , Tolerância ao Exercício , Masculino , Humanos , Adolescente , Consumo de Oxigênio/fisiologia , Hipóxia , Adaptação Fisiológica , Oxigênio
2.
J Am Chem Soc ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560787

RESUMO

Poly(vinylidene fluoride) (PVDF)-based solid electrolytes with a Li salt-polymer-little residual solvent configuration are promising candidates for solid-state batteries. Herein, we clarify the microstructure of PVDF-based composite electrolyte at the atomic level and demonstrate that the Li+-interaction environment determines both interfacial stability and ion-transport capability. The polymer works as a "solid diluent" and the filler realizes a uniform solvent distribution. We propose a universal strategy of constructing a weak-interaction environment by replacing the conventional N,N-dimethylformamide (DMF) solvent with the designed 2,2,2-trifluoroacetamide (TFA). The lower Li+ binding energy of TFA forms abundant aggregates to generate inorganic-rich interphases for interfacial compatibility. The weaker interactions of TFA with PVDF and filler achieve high ionic conductivity (7.0 × 10-4 S cm-1) of the electrolyte. The solid-state Li||LiNi0.8Co0.1Mn0.1O2 cells stably cycle 4900 and 3000 times with cutoff voltages of 4.3 and 4.5 V, respectively, as well as deliver superior stability at -20 to 45 °C and a high energy density of 300 Wh kg-1 in pouch cells.

3.
PhytoKeys ; 239: 267-273, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577245

RESUMO

Oxalisxishuiensis, a new species of Oxalidaceae from Danxia landforms of Xishui County, Guizhou, China, is described and illustrated. It is morphologically similar to O.wulingensis by the two lateral leaflets arranged at about 180° angle and oblong pink petals with lilac veins, but clearly differs from the latter by leaflets almost as long as wide, obliquely obcordate lateral leaflets, shorter peduncles, longer capsule (1.2-1.5 cm vs. 0.5-0.7 cm) and alveolate seeds.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38597280

RESUMO

The powerful capability of multi-stimulus-responsive luminescent hydrogen-bonded organic frameworks (HOFs) to respond to external chemical or physical stimuli in various manners makes them appealing in the luminescence anti-counterfeiting field. Herein, a novel Eu3+-functionalized HOF (Eu@GC-2) that combines the emission of HOFs with the characteristic emission of Eu3+ ions has been successfully synthesized, which can generate various fluorescence at different excitation wavelengths. Eu@GC-2 has enormous potential as a raw material for a paper-based sensor that is designed for detecting the pesticides thiram and caffeic acid in crops with favorable selectivity, anti-interference, and high efficiency. Based on the above excellent properties, Ln3+-functionalized HOFs (Ln@GC-2) were then employed to produce four luminescent anti-counterfeiting inks. With the incorporation of back-propagation neural network and Gray code conversion functions, a multi-stimulus-responsive luminescent anti-counterfeiting platform, coregulated by the excitation light and the chemical reagent, has been constructed. This approach can not only achieve multiple encryptions and fast information identification but also enhance the code-breaking complexity, making it an efficient strategy for information encryption and decryption.

6.
J Craniofac Surg ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568861

RESUMO

PURPOSE: Iatrogenic lip injury may occur during oral and maxillofacial surgical procedures. This study aimed to evaluate the effect of oral retractors on iatrogenic lip injury prevention during intraoral procedures of oral and maxillofacial surgery. METHODS: We conducted a randomized controlled trial and included patients who underwent intraoral procedures of oral and maxillofacial surgery. Patients were randomly allocated to receive oral retractor (intervention group) or traditional procedure without lip protection (control group). The incidence of lip injury was the outcome variable. Other study variables included surgical time and satisfaction of patients and surgeons with treatment experience evaluated by visual analog scale (VAS). Student t test and χ2 test were used to compare both groups' variables and measure the relationship between the predictor variable and the outcome variable. P<0.05 was considered significant for all analyses. RESULTS: A total of 114 patients were included, with 56 allocated to intervention group and 58 to control group. The results showed that the application of an oral retractor did not significantly increase surgical time (P=0.318). A total of 12 patients had lip injury, with 1 in the intervention group and 11 in the control group (P=0.003). For the assessment of satisfaction with treatment experience, the intervention group had significantly higher VAS scores for doctors and patients (P<0.05). CONCLUSIONS: We found that the oral retractor was a good tool for iatrogenic lip injury prevention in oral and maxillofacial surgical procedures and could be considered in clinical treatment.

7.
RSC Adv ; 14(16): 10953-10961, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38577433

RESUMO

Purine nucleoside ester is one of the derivatives of purine nucleoside, which has antiviral and anticancer activities. In this work, a continuous flow synthesis of purine nucleoside esters catalyzed by lipase TL IM from Thermomyces lanuginosus was successfully achieved. Various parameters including solvent, reaction temperature, reaction time/flow rate and substrate ratio were investigated. The best yields were obtained with a continuous flow microreactor for 35 min at 50 °C with the substrate ratio of 1 : 5 (nucleosides to vinyl esters) in the solvent of tert-amyl alcohol. 12 products were efficiently synthesized with yields of 78-93%. Here we reported for the first time the use of lipase TL IM from Thermomyces lanuginosus in the synthesis of purine nucleoside esters. The significant advantages of this methodology are a green solvent and mild conditions, a simple work-up procedure and the highly reusable biocatalyst. This research provides a new technique for rapid synthesis of anticancer and antiviral nucleoside drugs and is helpful for further screening of drug activity.

8.
Nat Commun ; 15(1): 3120, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600106

RESUMO

Salmonella utilizes a type 3 secretion system to translocate virulence proteins (effectors) into host cells during infection1. The effectors modulate host cell machinery to drive uptake of the bacteria into vacuoles, where they can establish an intracellular replicative niche. A remarkable feature of Salmonella invasion is the formation of actin-rich protuberances (ruffles) on the host cell surface that contribute to bacterial uptake. However, the membrane source for ruffle formation and how these bacteria regulate membrane mobilization within host cells remains unclear. Here, we show that Salmonella exploits membrane reservoirs for the generation of invasion ruffles. The reservoirs are pre-existing tubular compartments associated with the plasma membrane (PM) and are formed through the activity of RAB10 GTPase. Under normal growth conditions, membrane reservoirs contribute to PM homeostasis and are preloaded with the exocyst subunit EXOC2. During Salmonella invasion, the bacterial effectors SipC, SopE2, and SopB recruit exocyst subunits from membrane reservoirs and other cellular compartments, thereby allowing exocyst complex assembly and membrane delivery required for bacterial uptake. Our findings reveal an important role for RAB10 in the establishment of membrane reservoirs and the mechanisms by which Salmonella can exploit these compartments during host cell invasion.


Assuntos
Infecções por Salmonella , Salmonella typhimurium , Humanos , Salmonella typhimurium/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções por Salmonella/microbiologia , Membrana Celular/metabolismo , Membranas/metabolismo , Células HeLa
9.
J Phys Chem A ; 128(16): 3170-3179, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38624170

RESUMO

We perform a high-level ab initio study on 20 electronic states of monochlorosilylene (HSiCl) using an internally contracted multireference configuration interaction method including Davidson correction (icMRCI+Q). The spin-orbit coupling (SOC) effect is investigated, leading to splitting of the 20 spin-orbit-free states into 50 spin-orbit-coupled states. Vertical transition energies, oscillator strengths, and potential energy curves are presented with and without considering the SOC effect. Analysis indicates that the SOC effect plays an important role, especially for the high-lying excited states of HSiCl. The state interaction and the dynamics of the electronic states of HSiCl in the ultraviolet region are discussed based on our calculation results. Our study paves the way to understanding the behavior of electronic excited states of monochlorosilylene.

10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(2): 262-267, 2024 Apr 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38597087

RESUMO

Robotic surgery is known as the "third technological revolution" in the field of surgery, and is an important milestone in the development of modern surgery. However, our country's innovative surgical robot industry is still in its early stages, and it is only being utilized in certain surgical fields. To explore the effectiveness of the application of domestic surgical robot in oral and maxillofacial surgery, the author successfully completed a case of benign parotid tumor resection with the assistance of a domestic autonomous robot. The operation was successful, facial nerve function was preserved, and postoperative wound healing was good.


Assuntos
Neoplasias Parotídeas , Procedimentos Cirúrgicos Robóticos , Humanos , Neoplasias Parotídeas/cirurgia , Neoplasias Parotídeas/patologia , Glândula Parótida/cirurgia , Glândula Parótida/patologia , China
11.
Small ; : e2310966, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38616767

RESUMO

Autophagy, vital for removing cellular waste, is triggered differently by small molecules and nanoparticles. Small molecules, like rapamycin, non-selectively activate autophagy by inhibiting the mTOR pathway, which is essential for cell regulation. This can clear damaged components but may cause cytotoxicity with prolonged use. Nanoparticles, however, induce autophagy, often causing oxidative stress, through broader cellular interactions and can lead to a targeted form known as "xenophagy." Their impact varies with their properties but can be harnessed therapeutically. In this review, the autophagy induced by nanoparticles is explored and small molecules across four dimensions: the mechanisms behind autophagy induction, the outcomes of such induction, the toxicological effects on cellular autophagy, and the therapeutic potential of employing autophagy triggered by nanoparticles or small molecules. Although small molecules and nanoparticles each induce autophagy through different pathways and lead to diverse effects, both represent invaluable tools in cell biology, nanomedicine, and drug discovery, offering unique insights and therapeutic opportunities.

12.
Chemistry ; : e202400714, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622057

RESUMO

Quantum chemical calculations using ab initio methods at the MRCI+Q(8,9)/def2-QZVPPD and CCSD(T)/def2-QZVPPD levels as well as density functional theory are reported for the diatomic molecules AeN- (Ae = Ca, Sr, Ba). The nature of the bonds is analyzed with a variety of methods. The anions CaN- and SrN- have electronic triplet (3Π) ground states with nearly identical bond dissociation energies De ~57 kcal/mol calculated at the MRCI+Q(8,9)/def2-QZVPPD level of theory. In contrast, the heavier homologue BaN- has a singlet (1Σ+) ground state, which is only 1.1 kcal/mol below the triplet (3Σ-) state. The computed bond dissociation energy of (1Σ+) BaN- is 68.4 kcal/mol. The calculations at the CCSD(T)-full/def2-QZVPPD and BP86-D3(BJ)/def2-QZVPPD levels of theory are in reasonable agreement with the MRCI+Q(8,9)/def2-QZVPPD data except for the singlet (1Σ+) state, which has a large multireference character. The calculated atomic partial charges given by the CM5, Voronoi and Hirshfeld methods suggest small to medium-sized charge donation toward Ae atom Ae←N- for most electronic states. In contrast, the NBO method predicts for all species medium to large electronic charge donation toward nitrogen Ae→N-, which is due to the neglect of the (n)p AOs of Ae atoms as genuine valence orbitals.

13.
Angew Chem Int Ed Engl ; : e202402205, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38606878

RESUMO

Developing candidate materials which possess the ability of both selective detection and efficient capture of precious metal gold is highly desirable for environment and economy. However, most of reported materials only focus on single function, which seriously restricts their practical application as probes or adsorbents. Herein, a two dimensional (2D) acridine-based covalent organic framework (TpDa-COF) is prepared via the linkage of imine bonds for gold detection and adsorption. The synthesized COF can achieve both fluorescence and colorimetric dual sensing for Au3+ in a low concentration range (0.1 - 1.5 ppm) with the limit of detection (LOD) of 0.036 ppm. Impressively, the selectivity of TpDa-COF for the detection of Au3+ is admirable (Fe3+, Fe2+ and Cu2+ for negligible influence on its fluorescence). In addition, TpDa-COF exhibits ultrahigh adsorption capacity of 982.5 mg·g-1 for gold at pH = 4, which is attributed the synergistic effect of both selective coordination and reductive process of Au(III) to Au(0). Meanwhile, both positive entropy change (ΔS = 76.07 J·mol-1·K-1) and high distribution coefficient (Kd = 12484.8 mL·g-1) confirm the good affinity between TpDa-COF framework and gold. This work gives us a new insight to prepare COF with pyridine nitrogen sites for gold detection and adsorption.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38607211

RESUMO

Objective: To explore the application value of transabdominal ultrasonography in the diagnosis of gastrointestinal malignant tumors. Methods: This study retrospectively analyzed the transabdominal ultrasound imaging data of 284 patients with gastrointestinal tumors admitted to our hospital from April 2019 to March 2022 and assessed the accuracy of transabdominal ultrasound in diagnosing different types of gastrointestinal tumor diseases. The diagnostic accuracy of transabdominal ultrasonography for TNM staging of gastrointestinal malignancies was calculated. Results: The sensitivity and specificity of transabdominal ultrasonography in the diagnosis of gastric cancer were (82.40% and 83.72%, respectively), colon cancer (77.78% and 88.35%, respectively), gastric stromal tumor (95.45% and 93.65%, respectively), gastric lymphoma (72.22% and 94.66%, respectively), colorectal lymphoma (80.00% and 95.42%, respectively), gastric mucosal hypertrophy (85.71% and 96.69%, respectively), and pyloric hypertrophy (92.59% and 97.79%, respectively). Among the 284 patients included, 152 patients had malignant tumors, including 34 patients with stage I, 30 patients with stage II, 51 patients with stage III, and 37 patients with stage IV. The accuracy of transabdominal ultrasonography for TNM staging of gastrointestinal malignancies was 85.53% (130/152). Conclusion: Transabdominal ultrasonography shows promise as a diagnostic tool for gastrointestinal malignant tumors; however, it is recommended to be used in conjunction with other detection methods such as fibrous gastrointestinal tract examination to minimize the risk of missed diagnoses and misdiagnoses. The study highlights the potential of transabdominal ultrasonography as a non-invasive and accessible diagnostic method for gastrointestinal malignancies. Further research and advancements in imaging technologies are crucial for enhancing diagnostic capabilities and improving patient outcomes in the future.

15.
Sci Total Environ ; : 172503, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38631628

RESUMO

The aquatic ecosystem, a repository for various pollutants, has been identified as a crucial zone where microplastics (MPs) serve as vectors for antibiotics, facilitating their spread. Despite this, the influence of MPs on the toxicity of antibiotics remains a topic of debate. In this study, we conduct a global meta-analysis, examining 730 datasets from 29 laboratory studies. Our findings reveal that the impact of MPs on antibiotic toxicity is highly dependent on biological response pathways, microplastic concentration, antibiotic properties, and exposure time. We observed that MPs amplify the accumulation of antibiotics in aquatic organisms, significantly heightening their adverse effects on growth, development, and immune functions. Intriguingly, MPs appear to mitigate the reproductive toxicity caused by antibiotics. A notable inverse relationship was identified between antibiotic toxicity and microplastic concentration and exposure time. Furthermore, antibiotic concentration predominantly affects growth, development, and reproductive health, whereas exposure time is critical in determining antibiotic accumulation and immune-related toxicity. These insights underscore that microplastic co-exposure can modify the toxicological profile of antibiotics. The outcomes of this research enhance our comprehensive understanding of the intricate combined effects of MPs and antibiotics on aquatic life, emphasizing the necessity for informed scientific management of these emerging contaminants.

16.
RSC Adv ; 14(18): 12294-12302, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38633491

RESUMO

The excited-state energy transfer widely exists in mixed-material systems and devices. The modulation of an electric field on the energy transfer in photoluminescence has been demonstrated. However, to date, no studies on the electric-field modulation of the excited-state energy transfer in organic optoelectronic devices have been reported. Herein, we investigate the effect of an electric field on the energy transfer in the poly(N-vinylcarbazole) (PVK) thin films doped with iridium(iii)[bis(4,6-difluorophenyl)pyridinato-N,C2']-tetrakis(1-pyrazolyl)borate (Fir6) and 5,6,11,12-tetraphenylnaphthacene (rubrene) (PVK:Fir6:rubrene) and the corresponding light-emitting diodes. Combined with the Onsager model describing electric-field enhanced exciton dissociation, we find that the electric field increases the rate of Dexter energy transfer from Fir6 to rubrene in the films and the diodes. The voltage-dependent color shift in the PVK:Fir6:rubrene light-emitting diodes can be explained by the electric-field enhanced Dexter energy transfer from Fir6 to rubrene. Our findings are important for the control of energy transfer process in organic optoelectronic devices by an electric field for desirable applications.

17.
Water Res ; 256: 121652, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38657313

RESUMO

The safety of municipal sewage sludge has raised great concerns because of the accumulation of large-scale endocrine disrupting chemicals in the sludge during wastewater treatment. The presence of contaminants in sludge can cause secondary pollution owing to inappropriate disposal mechanisms, posing potential risks to the environment and human health. Effect-directed analysis (EDA), involving an androgen receptor (AR) reporter gene bioassay, fractionation, and suspect and nontarget chemical analysis, were applied to identify causal AR agonists in sludge; 20 of the 30 sludge extracts exhibited significant androgenic activity. Among these, the extracts from Yinchuan, Kunming, and Shijiazhuang, which held the most polluted AR agonistic activities were prepared for extensive EDA, with the dihydrotestosterone (DHT)-equivalency of 2.5 - 4.5 ng DHT/g of sludge. Seven androgens, namely boldione, androstenedione, testosterone, megestrol, progesterone, and testosterone isocaproate, were identified in these strongest sludges together, along with testosterone cypionate, first reported in sludge media. These identified androgens together accounted for 55 %, 87 %, and 52 % of the effects on the sludge from Yinchuan, Shijiazhuang, and Kunming, respectively. This study elucidates the causative androgenic compounds in sewage sludge and provides a valuable reference for monitoring and managing androgens in wastewater treatment.

18.
Int Wound J ; 21(4): e14834, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38650426

RESUMO

A meta-analysis was conducted comprehensively to investigate the impact of evidence-based nursing (EBN) interventions on pressure injury (PI) in the intensive care unit (ICU) patients. Computer searches were performed, from databases inception to November 2023, in Wanfang, PubMed, China National Knowledge Infrastructure, Google Scholar, Embase, and Cochrane Library for randomized controlled trials (RCTs) on the application of EBN interventions in ICU patients. Two independent researchers conducted screenings of the literature, extracted data, and carried out quality evaluations. Stata 17.0 software was employed for data analysis. Overall, 25 RCTs, involving 2494 ICU patients, were included. It was found that compared to conventional care methods, the implementation of EBN interventions in ICU patients markedly decreased the occurrence of PI (odds ratio [OR]: 0.22, 95% confidence interval [CI]: 0.17-0.30, p < 0.001), delayed the onset time of pressure ulcers (standardized mean difference [SMD]: -1.61, 95% CI: -2.00 to -1.22, p < 0.001), and also improved nursing satisfaction (OR: 1.18, 95% CI: 1.14-1.23, p < 0.001). Our findings suggest the implementation of EBN interventions in the care of PI in ICU patients is highly valuable, can reduce the occurrence of PI, can delay the time of appearance, and is associated with relatively higher nursing satisfaction, making it worthy of promotion.

19.
Front Oncol ; 14: 1376498, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38651151

RESUMO

Objectives: This study aimed to examine Ki-67's correlation with clinicopathological characteristics of head and neck squamous cell carcinoma (HNSCC), evaluate its prognostic significance, and develop a Ki-67 integrated prognostic model. Methods: The retrospective study included 764 HNSCC patients hospitalized from 2012 to 2022. Data were sourced from medical records and immunohistochemical analysis of surgical specimens. Results: Ki-67 expression was significantly associated with sex, pathological grade, clinical stage, and metastasis, but not with age or recurrence. Higher Ki-67 levels were linked to poorer prognosis, as indicated by Kaplan-Meier survival analysis. Utilizing a Cox proportional hazards model, four prognostic factors were identified: age, recurrence, metastasis, and Ki-67 expression. These factors were used to construct a prognostic model and a nomogram. The model's predictive accuracy was confirmed by a high concordance index and a reliable calibration curve. Conclusion: Ki-67 expression in HNSCC patients correlates with several clinicopathological features and serves as a negative prognostic marker. A prognostic model incorporating Ki-67 was successfully developed, offering a new tool for patient prognosis assessment in HNSCC.

20.
Heart Fail Rev ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38498262

RESUMO

Heart failure (HF) can be caused by a variety of causes characterized by abnormal myocardial systole and diastole. Ca2+ current through the L-type calcium channel (LTCC) on the membrane is the initial trigger signal for a cardiac cycle. Declined systole and diastole in HF are associated with dysfunction of myocardial Ca2+ function. This disorder can be correlated with unbalanced levels of phosphorylation / dephosphorylation of LTCC, endoplasmic reticulum (ER), and myofilament. Kinase and phosphatase activity changes along with HF progress, resulting in phased changes in the degree of phosphorylation / dephosphorylation. It is important to realize the phosphorylation / dephosphorylation differences between a normal and a failing heart. This review focuses on phosphorylation / dephosphorylation changes in the progression of HF and summarizes the effects of phosphorylation / dephosphorylation of LTCC, ER function, and myofilament function in normal conditions and HF based on previous experiments and clinical research. Also, we summarize current therapeutic methods based on abnormal phosphorylation / dephosphorylation and clarify potential therapeutic directions.

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