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1.
Placenta ; 155: 52-59, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39128141

RESUMO

INTRODUCTION: Abnormal placental cord insertions (APCIs) are significant risk factors for pregnancy complications, encompassing marginal cord insertion (MCI), velamentous cord insertion (VCI), and vasa previa (VP). While ultrasound is the primary imaging modality, its accuracy can be limited by factors such as maternal obesity and fetal positioning. Complementary to ultrasound, magnetic resonance imaging (MRI) offers a more precise visualization of the fetus, placenta, and umbilical cord relationships. This study aims to investigate the diagnostic value of prenatal magnetic resonance imaging (MRI) for APCIs compared with prenatal ultrasound. METHODS: We retrospectively collected data from 613 patients who underwent prenatal placental ultrasound and MRI. Of those who were confirmed as APCIs through surgery or pathology, the prenatal MRI features were compared with prenatal ultrasound. The diagnostic efficacy of prenatal MRI and ultrasound for APCIs was assessed based on the clinicopathological findings. RESULTS: Fifty-six patients were confirmed as APCIs by surgery or pathology, comprising 31 marginal cord insertions (MCIs), 18 velamentous cord insertions (VCIs), 5 vasa previa (VP) cases, and 2 VCI cases combined with VP. Ultrasound examination showed 55.36 % sensitivity (31/56) and 98.38 % specificity (486/494) in diagnosing APCIs, whereas MRI demonstrated 87.50 % sensitivity (49/56) and 98.88 % specificity (531/537). CONCLUSION: For APCIs complicated by placental location or morphological abnormalities, MRI demonstrates superior diagnostic efficacy compared to ultrasound in late pregnancy.

2.
ACS Omega ; 9(17): 18893-18900, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38708236

RESUMO

During long-term storage of the liquid propellant N2O4, it absorbs H2O to form the N2O4(H2O)n system, and this in turn generates HNO3, HNO2, and other substances in the storage tank because of corrosion, which seriously affects the performance of weaponry. In this work, we carried out computational simulations of N2O4 with different masses of water based on ReaxFF, analyzed the reaction intermediates and products, and investigated the mechanism of the reaction of N2O4 with H2O and of N2O4(H2O)n. The results show that the reaction product ω(HNO3+HNO2) undergoes a rapid growth in the early stage of the reaction and then tends toward dynamic equilibrium; the potential energy of the system decreases with the increase of ω(H2O), the reaction rate increases, and the rate of decomposition of HNO2 to form HNO3 increases. When ω(H2O) is 0.2 or 1.0%, the intermediate products are N2O4H2O or N2O4(H2O)2, respectively, and the reaction proceeds along two paths; when ω(H2O) ≥ 2.0%, N2O4(H2O)3 appears as the intermediate product, HNO3 and HNO2 are directly produced in one step, and a stable current loop can be formed within the whole system.

3.
Langmuir ; 40(21): 10947-10956, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38752855

RESUMO

Many experimental and theoretical studies have shown that the mechanical properties of cells and the extracellular matrix can significantly affect the lifetime and strength of the adhesion clusters of molecular bonds. However, there are few studies on how the shape of the contact surface affects the lifetime and strength of the adhesion clusters of molecular bonds, especially theoretical studies in this area. An idealized model of focal adhesion is adopted, in which two rigid media are bonded together by an array of receptor-ligand bonds modeled as Hookean springs on a complex surface topography, which is described by three parameters: the surface shape factor ß, the length of a single identical surface shape L, and the amplitude of surface shapes w. In this study, systematic Monte Carlo simulations of this model are conducted to study the lifetime of the molecular bond cluster under linear incremental force loading and the strength of the molecular bond cluster under linear incremental displacement loading. We find that both small surface shape amplitudes and large surface shape factors will increase the lifetime and strength of the adhesion cluster, whereas the length of a single surface shape causes oscillations in the lifetime and strength of the cluster, and this oscillation amplitude is affected by the surface shape amplitude and the factor. At the same time, we also find that the pretension in the cluster will play a dominant role in the adhesion strength under large amplitudes and small factors of surface shapes. The physical mechanisms behind these phenomena are that the changes of the length of a single surface shape, the amplitude of surface shapes, and the surface shape factor cause the changes of stress concentration in the adhesion region, bond affinity, and the number of similar affinity bonds.

4.
J Colloid Interface Sci ; 660: 869-884, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38277843

RESUMO

Infiltration and activation of intratumoral T lymphocytes are critical for immune checkpoint blockade (ICB) therapy. Unfortunately, the low tumor immunogenicity and immunosuppressive tumor microenvironment (TME) induced by tumor metabolic reprogramming cooperatively hinder the ICB efficacy. Herein, we engineered a lactate-depleting MOF-based catalytic nanoplatform (LOX@ZIF-8@MPN), encapsulating lactate oxidase (LOX) within zeolitic imidazolate framework-8 (ZIF-8) coupled with a coating of metal polyphenol network (MPN) to reinforce T cell response based on a "two birds with one stone" strategy. LOX could catalyze the degradation of the immunosuppressive lactate to promote vascular normalization, facilitating T cell infiltration. On the other hand, hydrogen peroxide (H2O2) produced during lactate depletion can be transformed into anti-tumor hydroxyl radical (•OH) by the autocatalytic MPN-based Fenton nanosystem to trigger immunogenic cell death (ICD), which largely improved the tumor immunogenicity. The combination of ICD and vascular normalization presents a better synergistic immunopotentiation with anti-PD1, inducing robust anti-tumor immunity in primary tumors and recurrent malignancies. Collectively, our results demonstrate that the concurrent depletion of lactate to reverse the immunosuppressive TME and utilization of the by-product from lactate degradation via cascade catalysis promotes T cell response and thus improves the effectiveness of ICB therapy.


Assuntos
Estruturas Metalorgânicas , Neoplasias , Humanos , Ácido Láctico/farmacologia , Estruturas Metalorgânicas/farmacologia , Peróxido de Hidrogênio/farmacologia , Linfócitos T , Imunoterapia , Linhagem Celular Tumoral , Microambiente Tumoral
5.
ACS Nano ; 18(5): 4189-4204, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38193384

RESUMO

cGAS-STING signaling plays a critical role in radiotherapy (RT)-mediated immunomodulation. However, RT alone is insufficient to sustain STING activation in tumors under a safe X-ray dose. Here, we propose a radiosensitization cooperated with cGAS stimulation strategy by engineering a core-shell structured nanosized radiosensitizer-based cGAS-STING agonist, which is constituted with the hafnium oxide (HfO2) core and the manganese oxide (MnO2) shell. HfO2-mediated radiosensitization enhances immunogenic cell death to afford tumor associated antigens and adequate cytosolic dsDNA, while the GSH-degradable MnO2 sustainably releases Mn2+ in tumors to improve the recognition sensitization of cGAS. The synchronization of sustained Mn2+ supply with cumulative cytosolic dsDNA damage synergistically augments the cGAS-STING activation in irradiated tumors, thereby enhancing RT-triggered local and system effects when combined with an immune checkpoint inhibitor. Therefore, the synchronous radiosensitization with sustained STING activation is demonstrated as a potent immunostimulation strategy to optimize cancer radio-immuotherapy.


Assuntos
Háfnio , Compostos de Manganês , Neoplasias , Humanos , Compostos de Manganês/farmacologia , Óxidos/farmacologia , Óxidos/uso terapêutico , Imunoterapia , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Nucleotidiltransferases
6.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1026577

RESUMO

The construction of urban medical groups is an important supply-side reform and exploration of Chinese urban health service system.It analyzes and discusses the interest generation mechanism,the dialectical relationship between public interests and economic interests and the balancing strategy of urban medical group construction,and proposes that the construction of urban medical groups mainly generates new value through comprehensive medical care,large-scale development,homogeneous services,digital construction and technology innovation,which can bring about optimizing the allocation of medical treatment resources,improving the homogeneity level and innovation ability of regional medical services,and strengthening regional primary medical services and other public interests.It can also bring about improvements in service efficiency,capacity and volume,which in turn generate economic benefits.The pursuit of public and economic interests in the construction of urban medical groups has potential value conflicts in terms of service positioning,cost and accessibility,effectiveness and rationality,and at the same time,there is a synergy mechanism in fulfilling social responsibilities,optimizing the utilization of medical resources,and promoting medical innovation and high-quality development.In the pilot construction of urban medical groups,public interests and economic interests should be viewed dialectically,the role of local governments in policy guidance,supervision and incentives should be explored,a focus on resource optimization,innovation-driven or high-quality development to promote the synergy of public interests and economic interests should be emphasized,and public participation should be strengthened and a performance evaluation mechanism should be established.

7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1029030

RESUMO

After kidney transplantation , timely detection of changes in transplanted kidney function may guide clinical managements and prevent or delay irreversible damage to transplanted kidney. Functional magnetic resonance imaging (fMRI) of transplanted kidney is a promising non-invasive technique of acquiring microstructural and microfunctional profiles of transplanted kidney. In recent years, various diffusion imaging modalities, arterial spin labeling (ASL) and blood oxygen level dependent-magnetic resonance imaging (BOLD-MRI) have gradually been applied for transplant kidneys. Transplant kidney function may be evaluated non-invasively from such microscopic perspectives as water molecule diffusion, blood flow perfusion and blood oxygen level. This review focused upon evaluating the renal function and identifying the causes of the renal function decline of transplanted kidney through various fMRI techniques and provide new rationales for clinical diagnosis.

8.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1002581

RESUMO

BACKGROUND/OBJECTIVES@#Tibetan tea is a kind of dark tea, due to the inherent complexity of natural products, the chemical composition and beneficial effects of Tibetan tea are not fully understood. The objective of this study was to unravel the composition of Tibetan tea using knowledge-guided multilayer network (KGMN) techniques and explore its potential antioxidant and hypolipidemic mechanisms in mice.MATERIALS/METHODS: The C57BL/6J mice were continuously gavaged with Tibetan tea extract (T group), green tea extract (G group) and ddH 2 O (H group) for 15 days. The activity of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) in mice was detected.Transcriptome sequencing technology was used to investigate the molecular mechanisms underlying the antioxidant and lipid-lowering effects of Tibetan tea in mice. Furthermore, the expression levels of liver antioxidant and lipid metabolism related genes in various groups were detected by the real-time quantitative polymerase chain reaction (qPCR) method. @*RESULTS@#The results showed that a total of 42 flavonoids are provisionally annotated in Tibetan tea using KGMN strategies. Tibetan tea significantly reduced body weight gain and increased T-AOC and SOD activities in mice compared with the H group. Based on the results of transcriptome and qPCR, it was confirmed that Tibetan tea could play a key role in antioxidant and lipid lowering by regulating oxidative stress and lipid metabolism related pathways such as insulin resistance, P53 signaling pathway, insulin signaling pathway, fatty acid elongation and fatty acid metabolism. @*CONCLUSIONS@#This study was the first to use computational tools to deeply explore the composition of Tibetan tea and revealed its potential antioxidant and hypolipidemic mechanisms, and it provides new insights into the composition and bioactivity of Tibetan tea.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1028602

RESUMO

Objective:To investigate the mediating effect of inflammatory factors in the association between low density lipoprotein-cholesterol(LDL-C) and thyroid associated ophthalmopathy(TAO).Methods:This study was a prospective study, which icluded a total of 86 patients with Graves′ disease who attended the Department of Endocrinology of the First Affiliated Hospital of Zhengzhou University from January 2021 to June 2022. Among them, there were 56 patients with Graves′ disease accompanied by TAO, including 30 cases in the inactive group and 26 in the active group. Additionally, there were 30 cases having Graves′ disease alone. The relationship between LDL-C, inflammatory factors, and the onset and activity of TAO were analyzed using binary logistic regression. Mediation analysis was used to explore the mediating effect of inflammatory factors in the association between LDL-C and TAO onset and activity.Results:Interleukin(IL) -6 was a potential mediator that linking the association between LDL-C and TAO onset: LDL-C had a direct effect on TAO(Total effect value=0.274, 95% CI 0.161-0.386), while IL-6(mediated effect=0.067, 95% CI 0.011-0.123) and IL-17(mediated effect=0.042, 95% CI 0.007-0.077) partially mediated the effect of LDL-C on TAO, accounting for 24.45% and 15.33% of the total effect, respectively. IL-6 was a potential mediator of the association between LDL-C and TAO activity: LDL-C had a direct effect on TAO activity(Total effect value=0.320, 95% CI 0.204-0.435), and IL-6(mediated effect=0.103, 95% CI 0.021-0.185) partially mediated the effect of LDL-C on TAO activity, with a mediation effect of 32.19%. Conclusion:IL-6 plays a partiall mediating role in the association of LDL-C with TAO onset and activity.

10.
Acta Physiologica Sinica ; (6): 333-352, 2022.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-939569

RESUMO

The mechanisms underlying exercise-induced neuroprotective effects after traumatic brain injury (TBI) remained elusive, and there is a lack of effective treatments for TBI. In this study, we investigated the effects of an integrative approach of exercise and Yisaipu (TNFR-IgG fusion protein, TNF inhibitor) in a mouse TBI model. Male C57BL/6J mice were randomly assigned to a sedentary group or a group that followed a voluntary exercise regimen. The effects of 6-week prophylactic preconditioning exercise (PE) alone or in combination with post-TBI Yisaipu treatment on moderate TBI associated deficits were examined. The results showed that combined treatments of PE and post-TBI Yisaipu were superior to single treatments on reducing sensorimotor and gait dysfunctions in mice. These functional improvements were accompanied by reduced systemic inflammation largely via decreased serum TNF-α, boosted autophagic flux, and mitigated lesion volume after TBI. Given these neuroprotective effects, composite approaches such as a combination of exercise and TNF inhibitor may be a promising strategy for facilitating functional recovery from TBI and are worth further investigation.


Assuntos
Animais , Masculino , Camundongos , Lesões Encefálicas Traumáticas/patologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Recuperação de Função Fisiológica , Inibidores do Fator de Necrose Tumoral
11.
Chinese Circulation Journal ; (12): 952-955, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-657464

RESUMO

Objective: To conduct a knowledge survey on heart failure (HF) guidelines for HF diagnosis and treatment in physicians in China. Methods: A questionnaire including15 multiple-choice and 10 blank-filling questions was developed based on Chinese HF diagnosis and treatment guidelines 2014. The survey was conducted in physicians who registered at Chinese HF study from 88 hospitals in China and the knowledge level was presented by the correction rate of questionnaire survey. Results: A total of 2146 physicians finished the survey including 56.2% female and 43.8% male with the mean age of (35.6±7.6) years. The ratios of resident, attending physician, associate chief physician and chief physician were 28.2%, 43.6%, 20.3% and 7.9% respectively; the ratios of cardiovascular specialists, physician and general practitioners were 62.1%, 28.8%and 9.1% respectively. Physicians from community hospital, 2nd grade hospital and 3rd grade hospital were 5.4%, 26.5%, and 68.2% respectively. The correct answer for 15 multiple-choice questions was only 32.6% and for 10 blank-filling questions regarding the target doses of anti-HF drugs was 42.5%. Physicians with the higher professional title had greater awareness of HF guidelines than those with the lower title, P<0.001. The compliance and command to HF guidelines were different among hospital levels, P<0.001; the command to HF prevention and treatment were different among physicians in different practice scopes, P<0.001. Conclusion: The knowledge for HF diagnosis and treatment had deficiency in physicians in China, further systemically study should be enforced.

12.
Chinese Circulation Journal ; (12): 952-955, 2017.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-659578

RESUMO

Objective: To conduct a knowledge survey on heart failure (HF) guidelines for HF diagnosis and treatment in physicians in China. Methods: A questionnaire including15 multiple-choice and 10 blank-filling questions was developed based on Chinese HF diagnosis and treatment guidelines 2014. The survey was conducted in physicians who registered at Chinese HF study from 88 hospitals in China and the knowledge level was presented by the correction rate of questionnaire survey. Results: A total of 2146 physicians finished the survey including 56.2% female and 43.8% male with the mean age of (35.6±7.6) years. The ratios of resident, attending physician, associate chief physician and chief physician were 28.2%, 43.6%, 20.3% and 7.9% respectively; the ratios of cardiovascular specialists, physician and general practitioners were 62.1%, 28.8%and 9.1% respectively. Physicians from community hospital, 2nd grade hospital and 3rd grade hospital were 5.4%, 26.5%, and 68.2% respectively. The correct answer for 15 multiple-choice questions was only 32.6% and for 10 blank-filling questions regarding the target doses of anti-HF drugs was 42.5%. Physicians with the higher professional title had greater awareness of HF guidelines than those with the lower title, P<0.001. The compliance and command to HF guidelines were different among hospital levels, P<0.001; the command to HF prevention and treatment were different among physicians in different practice scopes, P<0.001. Conclusion: The knowledge for HF diagnosis and treatment had deficiency in physicians in China, further systemically study should be enforced.

13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-852611

RESUMO

Objective: To study the chemical constituents in the rare medicinal herb Oreorchas patens in Changbai Mountain for better utilization of the resource. Methods: The drug was used as crude material, the extract was obtained with 95% ethanol firstly, and then with ethyl acetate (EtOAc). The EtOAc extract was further isolated and purified with various chromatographic methods, including silica gel, ODS, and Sephadex LH-20 columns. Finally the isolated compounds were characterized with their physical chemical properties and based on their 1H-NMR and 13C-NMR data. Results: Eleven compounds were obtained from the EtOAc extract and identified as β-sitosterol (1), β-daucosterol (2), dioctyl phthalate (3), butyl-isobutyl-phthalate (4), diamyl phthalate (5), β-sitosterol acetate (6), dibutyl phthalate (7), dibutyl terephthalate (8), cirrhopetalanthin (9), pentacosane (10), and hexatriacontane (11). Conclusion: Compounds 3-11 are isolated from O. patens for the first time.

14.
Chongqing Medicine ; (36): 1843-1845, 2014.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-447530

RESUMO

Objective To apply nitric oxide(NO) electrochemical microsensor in the real time detection of NO released from RAW 264 .3 cells infected by E .coli ,and to explore the application value of this NO microsensor in the research area of infection im‐munity against bacterium .Methods Taking NO microsensor to detect NO released from RAW 264 .3 cells respectively stimulated by E .coli of different densities and of 1 × 107 mL -1 for different time .Results The level of NO released from RAW 264 .3 cells was enhanced obviously when incubated with E .coli as compared with that of normal cells and the extent of incersase depended on the density of E .coli (P<0 .01) .The released level of NO increased gradually from the beginning and reached its peal at the time of 12 h then decreased slowly when incubated with E .coli of 1 × 107 mL -1 .Conclusion The electrochemical microsensor was applied in the real time detection of NO released from macrophages activated by E .coli successfully .

15.
Chongqing Medicine ; (36): 3002-3003,3007, 2013.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-555861

RESUMO

Objective To explore the performance of the novel nitric oxide(NO) electrochemical microsensor based on Au nano-particles(nano-Au) modified glass-fiber .Methods With columnar glass-fiber as the substrate material ,the in-situ chemical seed-growth technology was adopted to fabricate one kind of electrochemical microsensor based on gold nanoparticles pole electrodes and the amperometric response method was used to investigate the various properties of the NO microsensor .Results This microsensor had high sensitivity response to NO ,its linear range was 7 .2 nmol/L -11 .7μmol/L(r=0 .998) with a detection limit of 3 .6 nmol/L .Conclusion A novel electrochemical microsensor based on nano-Au pole electrode was fabricated .The NO microsensor posseses high sensitivity ,wide linear range ,good reproducibility and excellent anti-interference ability .

16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-305143

RESUMO

<p><b>OBJECTIVE</b>High noise levels (>70 dB) in the neonatal intensive care unit (NICU) are common in some primary hospitals. This study aimed to investigate the noise in the NICU on auditory system and intelligence development in premature infants.</p><p><b>METHODS</b>One hundred premature infants with respiratory distress syndrome who needed mechanical ventilation therapy were randomly divided into observation and control groups according to the use of earmuffs. The duration of mechanical ventilation therapy lasted for 2 to 15 days in the two groups. After weaning from mechanical ventilator, the auditory brainstem response, cranial B-ultrasonography, and the intelligence development assessment were performed.</p><p><b>RESULTS</b>The percentage of total (23% vs 47%) and mild hearing loss (15% vs 35%) in the observation group was significantly lower than that in the control group (p<0.05) 2 to 3 days after weaning from mechanical ventilator. The incidence of periventricular hemorrhage intraventricular hemorrhage (PVH-IVH) or periventricular leukomalacia (PVL) in the observation group was significantly lower than that in the control group (21% vs 42%; p<0.05). The intelligence development assessment performed in the first 6 and 12 months of life showed that the mental development index and the psychomotor development index in the observation group were much higher than those in the control group (p<0.05).</p><p><b>CONCLUSIONS</b>The noise in the NICU can result in mild hearing loss and retardation of intelligence development and increase the incidence of PVH-IVH and PVL in premature infants. The use of earmuff may reduce the adverse events.</p>


Assuntos
Feminino , Humanos , Recém-Nascido , Masculino , Hemorragia Cerebral , Epidemiologia , Desenvolvimento Infantil , Audição , Recém-Nascido Prematuro , Inteligência , Unidades de Terapia Intensiva Neonatal , Leucomalácia Periventricular , Epidemiologia , Ruído
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