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1.
J Mol Model ; 30(9): 303, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39115702

RESUMEN

CONTEXT: The DNAN/DNB eutectic is a high-energy explosive eutectic with superior safety and thermal stability compared to traditional melt-cast explosives. However, the addition of polymer binders can effectively enhance its mechanical properties, allowing for continued production demands without the need for changes to existing factory equipment. In this paper, a model of the DNAN/DNB eutectic explosive was established, and five different types of polymers-cis-1,4-polybutadiene (BR), ethylene-vinyl acetate copolymer (EVA), polyethylene glycol (PEG), fluorinated polymer (F2603), and polyvinylidene fluoride (PVDF)-were added to the (1 0 - 1), (1 0 1), and (0 1 1) cleavage planes, respectively, to form polymer-bonded explosives (PBXs). The stability, trigger bond length, mechanical properties, and detonation performance of the various polymer-bound PBXs were predicted retrogressively. Among the five PBX models, the DNAN/DNB/PEG model exhibited the highest binding energy and the shortest trigger bond length, indicating a significant improvement in stability, compatibility, and sensitivity compared to the original eutectic. Additionally, although the detonation performance of DNAN/DNB decreased after the addition of binders, the final results were still satisfactory. Overall, the DNAN/DNB/PEG model demonstrated excellent comprehensive performance, proving that among the many polymer binders, PEG is the optimal choice for DNAN/DNB. METHODS: Within the Materials Studio software, molecular dynamics (MD) simulations were employed to predict the properties of the DNAN/DNB eutectic PBX. The MD simulation timestep was set to 1 fs, with a cumulative simulation duration of 2 ns. A 2 ns MD simulation was conducted using the isothermal-isobaric ensemble (NPT). The COMPASS force field was applied, and the temperature was fixed at 295 K.

2.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3540-3547, 2024 Jul.
Artículo en Chino | MEDLINE | ID: mdl-39041125

RESUMEN

The chemical constituents from the stems and leaves of Artocarpus tonkinensis in Artocarpus of Moraceae were systematically studied by means of silica gel, octadecylsilyl(ODS), and Sephadex LH-20 gel column chromatographies, as well as preparative high-performance liquid chromatography(Pre-HPLC) and a variety of chromatographic separation techniques. The spectral data and physicochemical properties of the compounds were obtained from separation and compared with those of the compounds reported in the literature. As a result, 11 compounds isolated from the 90% ethanol extract of the stems and leaves of A. tonkinensis were identified as artocatonkine(1), 5,6,7,4'-tetramethoxyflavone(2), apigenin-4'-O-ß-D-glucoside(3), rayalinol(4), psorachalcone A(5), 4-ketopinoresinol(6), ficusesquilignan B(7), pinnatifidanin AI(8), pinnatifidanin A(9), O-methylmellein(10), and trans-4-hydroxymellein(11). Among these compounds, compound 1 was a new prenylated flavone, and compounds 2-11 were isolated from the plants belonging to the genus Artocarpus for the first time. Furthermore, all compounds 1-11 were evaluated for their anti-rheumatoid arthritis activities, and the MTS method was used to measure their inhibitory effects on the proliferation of synovioblasts in vitro. The results of activity evaluation showed that flavonoid compounds 1-3, 5, and lignan compounds 8 and 9 displayed significant anti-rheumatoid arthritis activities, showing the IC_(50) values in inhibiting the proliferation of synovioblasts MH7A from(6.38±0.06) µmol·L~(-1) to(168.58±0.28)µmol·L~(-1).


Asunto(s)
Artocarpus , Proliferación Celular , Hojas de la Planta , Tallos de la Planta , Artocarpus/química , Hojas de la Planta/química , Tallos de la Planta/química , Proliferación Celular/efectos de los fármacos , Humanos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Línea Celular , Estructura Molecular , Cromatografía Líquida de Alta Presión
3.
J Am Heart Assoc ; 13(14): e035337, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-38979802

RESUMEN

BACKGROUND: Statins are widely used for treating patients with ischemic stroke at risk of secondary cerebrovascular events. It is unknown whether Asian populations benefit from more intensive statin-based therapy for stroke recurrence. Therefore, in the present study we evaluated the effectiveness and safety of high-dose and moderate-dose statins for patients who had experienced mild ischemic stroke during the acute period. METHODS AND RESULTS: This multicenter prospective study included patients with mild ischemic stroke who presented within 72 hours of symptom onset. The outcomes of patients in the high-intensity and moderate-intensity statin treatment groups were compared, with the main efficacy outcome being stroke recurrence and the primary safety end point being intracranial hemorrhage. The propensity score matching method was employed to control for imbalances in baseline variables. Subgroup analyses were conducted to evaluate group differences. In total, the data of 2950 patients were analyzed at 3 months, and the data of 2764 patients were analyzed at 12 months due to loss to follow-up. According to the multivariable Cox analyses adjusted for potential confounders, stroke recurrence occurred similarly in the high-intensity statin and moderate-intensity statin groups (3 months: adjusted hazard ratio [HR], 1.12 [95% CI, 0.85-1.49]; P=0.424; 12 months: adjusted HR, 1.08 [95% CI, 0.86-1.34]; P=0.519). High-intensity statin therapy was associated with an increased risk of intracranial hemorrhage (3 months: adjusted HR, 1.81 [95% CI, 1.00-3.25]; P=0.048; 12 months: adjusted HR, 1.86 [95% CI, 1.10-3.16]; P=0.021). The results from the propensity score-matched analyses were consistent with those from the Cox proportional hazards analysis. CONCLUSIONS: Compared with moderate-intensity statin therapy, high-dose statin therapy may not decrease the risk of mild, noncardiogenic ischemic stroke recurrence but may increase the risk of intracranial hemorrhage. REGISTRATION: URL: www.chictr.org.cn/. Unique Identifier: ChiCTR1900025214.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Accidente Cerebrovascular Isquémico , Recurrencia , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Femenino , Masculino , Estudios Prospectivos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/diagnóstico , Anciano , Persona de Mediana Edad , Resultado del Tratamiento , Factores de Tiempo , Factores de Riesgo , Puntaje de Propensión , Hemorragias Intracraneales/inducido químicamente , Hemorragias Intracraneales/epidemiología , Índice de Severidad de la Enfermedad , Prevención Secundaria/métodos
4.
BMC Plant Biol ; 24(1): 453, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789944

RESUMEN

BACKGROUND: Impatiens is an important genus with rich species of garden plants, and its distribution is extremely extensive, which is reflected in its diverse ecological environment. However, the specific mechanisms of Impatiens' adaptation to various environments and the mechanism related to lignin remain unclear. RESULTS: Three representative Impatiens species,Impatiens chlorosepala (wet, low degree of lignification), Impatiens uliginosa (aquatic, moderate degree of lignification) and Impatiens rubrostriata (terrestrial, high degree of lignification), were selected and analyzed for their anatomical structures, lignin content and composition, and lignin-related gene expression. There are significant differences in anatomical parameters among the stems of three Impatiens species, and the anatomical structure is consistent with the determination results of lignin content. Furthermore, the thickness of the xylem and cell walls, as well as the ratio of cell wall thickness to stem diameter have a strong correlation with lignin content. The anatomical structure and degree of lignification in Impatiens can be attributed to the plant's growth environment, morphology, and growth rate. Our analysis of lignin-related genes revealed a negative correlation between the MYB4 gene and lignin content. The MYB4 gene may control the lignin synthesis in Impatiens by controlling the structural genes involved in the lignin synthesis pathway, such as HCT, C3H, and COMT. Nonetheless, the regulation pathway differs between species of Impatiens. CONCLUSIONS: This study demonstrated consistency between the stem anatomy of Impatiens and the results obtained from lignin content and composition analyses. It is speculated that MYB4 negatively regulates the lignin synthesis in the stems of three Impatiens species by regulating the expression of structural genes, and its regulation mechanism appears to vary across different Impatiens species. This study analyses the variations among different Impatiens plants in diverse habitats, and can guide further molecular investigations of lignin biosynthesis in Impatiens.


Asunto(s)
Impatiens , Lignina , Tallos de la Planta , Lignina/metabolismo , Tallos de la Planta/genética , Tallos de la Planta/anatomía & histología , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/metabolismo , Impatiens/genética , Impatiens/metabolismo , Impatiens/crecimiento & desarrollo , Ecosistema , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Adaptación Fisiológica/genética , Regulación de la Expresión Génica de las Plantas , Especificidad de la Especie , Genes de Plantas , Pared Celular/metabolismo , Pared Celular/genética
5.
J Transl Med ; 22(1): 488, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773576

RESUMEN

Ulcerative colitis (UC) is an idiopathic, chronic inflammatory condition of the colon, characterized by repeated attacks, a lack of effective treatment options, and significant physical and mental health complications for patients. The endoplasmic reticulum (ER) is a vital intracellular organelle in maintaining cellular homeostasis. Endoplasmic reticulum stress (ERS) is induced when the body is exposed to adverse external stimuli. Numerous studies have shown that ERS-induced apoptosis plays a vital role in the pathogenesis of UC. Mogroside V (MV), an active ingredient of Monk fruit, has demonstrated excellent anti-inflammatory and antioxidant effects. In this study, we investigated the therapeutic effects of MV on dextran sulfate sodium (DSS)-induced UC and its potential mechanisms based on ERS. The results showed that MV exerted a protective effect against DSS-induced UC in mice as reflected by reduced DAI scores, increased colon length, reduced histological scores of the colon, and levels of pro-inflammatory cytokines, as well as decreased intestinal permeability. In addition, the expression of ERS pathway including BIP, PERK, eIF2α, ATF4, CHOP, as well as the apoptosis-related protein including Caspase-12, Bcl-2 and Bax, was found to be elevated in UC. However, MV treatment significantly inhibited the UC and reversed the expression of inflammation signaling pathway including ERS and ERS-induced apoptosis. Additionally, the addition of tunicamycin (Tm), an ERS activator, significantly weakened the therapeutic effect of MV on UC in mice. These findings suggest that MV may be a therapeutic agent for the treatment of DSS-induced UC by inhibiting the activation of the ERS-apoptosis pathway, and may provide a novel avenue for the treatment of UC.


Asunto(s)
Apoptosis , Colitis Ulcerosa , Sulfato de Dextran , Estrés del Retículo Endoplásmico , Animales , Estrés del Retículo Endoplásmico/efectos de los fármacos , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/metabolismo , Apoptosis/efectos de los fármacos , Masculino , Ratones Endogámicos C57BL , Colon/patología , Colon/efectos de los fármacos , Triterpenos/farmacología , Triterpenos/uso terapéutico , Ratones , Citocinas/metabolismo , Permeabilidad/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
6.
Clin Hemorheol Microcirc ; 87(2): 171-185, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38607754

RESUMEN

OBJECTIVE: To investigate predictors of anticoagulation efficacy in deep venous thrombosis (DVT) by ultrasound elastography (UE). METHODS: The basic clinical, laboratory and ultrasound treatment data of fifty-eight patients with DVT were collected and analyzed. Then the results of ultrasound after 3-month anticoagulation treatment were compared among different groups. Multiple logistic regression analysis was used to identify independent risk factors that affected anticoagulation efficacy. The predictive efficacy of each independent risk factor was accessed by drawing operating characteristic (ROC) curves. RESULTS: According to the regression analysis, the elastic modulus (OR = 0.631, P = 0.001) and strain rate ratio (OR = 0.332, P = 0.006) were identified as independent risk factors for the effectiveness of anticoagulation therapy in patients with DVT. According to the ROC curves, elastic modulus and strain rate ratio could predict effective anticoagulation therapy for DVT, and the optimal threshold values were 22.10 kPa and 1.80 respectively. The corresponding AUC values were 0.879 and 0.854, with a sensitivity of 71.4% and 59.5%, a specificity of 93.7%, and a Youden index of 65.1% and 62.7%, respectively. CONCLUSIONS: The elastic modulus (≤22.10 kPa) or strain rate ratio (≤1.80) of the thrombus were independent predictors for the effectiveness of anticoagulation therapy.


Asunto(s)
Anticoagulantes , Diagnóstico por Imagen de Elasticidad , Extremidad Inferior , Trombosis de la Vena , Humanos , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/tratamiento farmacológico , Diagnóstico por Imagen de Elasticidad/métodos , Masculino , Anticoagulantes/uso terapéutico , Femenino , Persona de Mediana Edad , Extremidad Inferior/irrigación sanguínea , Extremidad Inferior/diagnóstico por imagen , Adulto , Anciano , Factores de Riesgo
7.
Hortic Res ; 11(3): uhae015, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38544551

RESUMEN

The nectar spur is an important feature of pollination and ecological adaptation in flowering plants, and it is a key innovation to promote species diversity in certain plant lineages. The development mechanism of spurs varies among different plant taxa. As one of the largest angiosperm genera, we have little understanding of the mechanism of spur development in Impatiens. Here, we investigated the initiation and growth process of spurs of Impatiens uliginosa based on histology and hormone levels, and the roles of AUXIN BINDING PROTEIN (ABP) and extensin (EXT) in spur development were explored. Our results indicate that the spur development of I. uliginosa is composed of cell division and anisotropic cell elongation. Imbalances in spur proximal-distal cell division lead to the formation of curved structures. Endogenous hormones, such as auxin and cytokinins, were enriched at different developmental stages of spurs. IuABP knockdown led to an increase in spur curves and distortion of morphology. IuEXT knockdown resulted in reduced spur length and loss of curve and inner epidermal papillae structures. This study provides new insights into the mechanism of spur development in core eudicots.

8.
World J Gastroenterol ; 30(2): 158-169, 2024 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-38312121

RESUMEN

BACKGROUND: Tumor budding (TB) has emerged as a promising independent prognostic biomarker in colorectal cancer (CRC). The prognostic role of TB has been extensively studied and currently affects clinical decision making in patients with stage I and II CRC. However, existing prognostic studies on TB in stage III CRC have been confined to small retrospective cohort studies. Consequently, this study investigated the correlation among TB categories, clinicopathological features, and prognosis in stage III-IV CRC to further enhance the precision and individualization of treatment through refined prognostic risk stratification. AIM: To analyze the relationship between TB categories and clinicopathological characteristics and assess their prognostic value in stage III-IV CRC to further refine the prognostic risk stratification of stage III-IV CRC. METHODS: The clinical data of 547 CRC patients were collected for this retrospective study. Infiltration at the front edge of the tumor buds was counted according to the 2016 International Tumor Budding Consensus Conference guidelines. RESULTS: Multivariate Cox proportional hazards regression analysis demonstrated that chemotherapy (P = 0.004), clinical stage IV (P < 0.001), ≥ 4 regional lymph node metastases (P = 0.004), left-sided colonic cancer (P = 0.040), and Bd 2-3 (P = 0.002) were independent prognostic factors in patients with stage III-IV CRC. Moreover, the density of tumor infiltrating lymphocytes was higher in Bd 1 than in Bd 2-3, both in the tumor stroma and its invasive margin. CONCLUSION: TB has an independent predictive prognostic value in patients with stage III-IV CRC. It is recommended to complete the TB report of stage III-IV CRC cases in the standardized pathological report to further refine risk stratification.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Humanos , Pronóstico , Estudios Retrospectivos , Estadificación de Neoplasias , Neoplasias Colorrectales/patología , Neoplasias del Colon/patología
9.
Adv Mater ; 36(15): e2310216, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38237136

RESUMEN

The sprayable hydrogel coatings that can establish robust adhesion onto diverse materials and devices hold enormous potential; however, a significant challenge persists due to monomer hydration, which impedes even coverage during spraying and induces inadequate adhesion post-gelation. Herein, a polycation-reinforced (PCR) surface bridging strategy is presented to achieve tough and sprayable hydrogel coatings onto diverse materials. The polycations offer superior wettability and instant electrostatic interactions with plasma-treated substrates, facilitating an effective spraying application. This PCR-based hydrogel coatings demonstrate tough adhesion performance to inert PTFE and silicone, including remarkable shear strength (161 ± 49 kPa for PTFE), interfacial toughness (198 ± 27 J m-2 for PTFE), and notable tolerance to cyclic tension (10 000 cycles, 200% strain, silicone). Meanwhile, this method can be applied to various hydrogel formulations, offering diverse functionalities, including underwater adhesion, lubrication, and drug delivery. Furthermore, the PCR concept enables the conformal construction of durable hydrogel coatings onto sophisticated medical devices like cardiovascular stents. Given its simplicity and adaptability, this approach paves an avenue for incorporating hydrogels onto solid surfaces and potentially promotes untapped applications.


Asunto(s)
Hidrogeles , Polielectrolitos , Siliconas , Politetrafluoroetileno , Reacción en Cadena de la Polimerasa
10.
Zootaxa ; 5397(1): 135-140, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38221214

RESUMEN

One new species of leaf katydids, Elimaea (Poaefoliana) kiukiangensis sp. nov. from the Himalaya-Hengduan Mountains region, is described, based on recently collected material. Illustrations of mounted specimens including male genitalia, and habitat images are provided. A distribution map is also provided. The types are deposited in Insect Collection of Institute of Zoology, Chinese Academy of Sciences, Beijing, China (IZCAS).


Asunto(s)
Ortópteros , Masculino , Animales , China , Ecosistema , Academias e Institutos , Distribución Animal
11.
Macromol Rapid Commun ; 45(5): e2300506, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38134364

RESUMEN

Condensation of 3,3'-diamino-2,2'-ethylene-bridged azobenzene with 1,2,4,5-tetrakis-(4-formylphenyl) benzene produces a visible light responsive porous 2D covalent organic framework, COF-bAzo-TFPB, with a large surface area, good crystallinity, and thermal and chemical stability. The results demonstrate that the elaborated designed linker can make azo unit on the COF-bAzo-TFPB skeleton undergo reversible photoisomerization. This work expands the application scope of covalent organic frameworks in photo-controlled release, uptake of guest molecules, dynamic photoswitching, and UV-sensitive functions.


Asunto(s)
Estructuras Metalorgánicas , Compuestos Azo , Benceno , Luz
12.
Zhongguo Zhong Yao Za Zhi ; 48(20): 5419-5437, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-38114136

RESUMEN

Curcuma wenyujin, as one of the eight Daodi-herbs in Zhejiang province, is widely used. It has the effects of eliminating stasis and dissipating mass, moving Qi and activating blood, and clearing heart and relieving depression. Modern studies have shown that it has anti-tumor, anti-inflammatory, anti-oxidation, anti-thrombus and liver-protecting effects and mainly contains sesquiterpenoids, monoterpenoids, diterpenoids, and curcumins. This paper reviews the research progress in the chemical constituents and pharmacological effects of C. wenyujin in the last decade, discusses the modern clinical applications combined with the traditional efficacy, and predicts its quality markers(Q-markers) from plant consanguinity, medicinal properties, efficacy, processing and measurability of chemical components based on the theory of Q-markers, so as to provide a reference for the establishment of a scientific quality evaluation system and the research and application of this herb in the future.


Asunto(s)
Curcuma , Antiinflamatorios , Curcuma/química , Hígado
13.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(6): 1058-1061, 2023 Dec 18.
Artículo en Chino | MEDLINE | ID: mdl-38101789

RESUMEN

OBJECTIVE: To investigate whether anti-phosphatidylserine/prothrombin antibodies and its IgG or IgM subtypes were correlated with unexplained recurrent miscarriages. METHODS: In our a single-center retrospective study, 283 patients with at least one unexplained miscarriage who visited the Third Hospital of Peking University between January 2021 and August 2023, aged between 18-40 years, and tested for anti-phosphatidylserine/prothrombin antibodies IgG or IgM subtypes, were included. The patients with either positive IgG or IgM anti-phosphatidylserine/prothrombin antibody were regarded as positive for anti-phosphatidylserine/prothrombin antibody. SPSS 26.0 software was used for statistical analysis. Chi-square test and Logistic regression analysis were used to study the correlation of anti-phosphatidylserine/prothrombin antibodies and its IgG or IgM subtypes with unexplained recurrent miscarriages. And the diagnostic sensitivity, specificity, the positive predictive value, the negative predictive value of anti-phosphatidylserine/prothrombin antibodies and its IgG or IgM subtypes in unexplained miscarriages was calculated with four-fold table. RESULTS: Chi-square analysis showed that anti-phosphatidylserine/prothrombin antibodies and its IgM subtypes were correlated with recurrent miscarriages (both P < 0.05), while the IgG subtype was not correlated with recurrent miscarriages (P>0.05). After adjusting with anticardiolipin antibodies, anti-ß2 glycoprotein antibodies, lupus anticoagulants, antinuclear antibodies, and age by Logistic regression analysis, anti-phosphatidylserine/prothrombin antibodies were correlated with unexplained recurrent miscarriages (OR=2.084, 95%CI 1.045-4.155, P < 0.05), and anti-phosphatidylserine/prothrombin antibody IgM subtypes were correlated with unexplained recurrent miscarriages (OR=2.368, 95%CI 1.187-4.722, P < 0.05).The sensitivity of anti-phosphatidylserine/prothrombin antibody in recurrent miscarriage was 65.43%, the specificity was 48.51%, the positive predictive value was 33.76%, and the negative predictive value was 77.78%. In the patients with recurrent miscarriages with negative classical antiphospholipid antibodies, the sensitivity of anti-phosphatidylserine/prothrombin antibody was 59.09%, the specificity was 63.23%, the positive predictive value was 40.63%, and the negative predictive value was 78.40%. The sensitivity of the anti-phosphatidylserine/prothrombin antibody IgM subtype for the diagnosis of recurrent miscarriage was 65.43%, the specificity was 50.99%, the positive predictive value was 34.87%, and the negative predictive value was 78.63%. CONCLUSION: Anti-phosphatidylserine/prothrombin antibody and IgM subtype antibody are correlated with unexplained recurrent miscarriages in patients with at least one unexplained miscarriage. Whether positive anti-phosphatidylserine/prothrombin antibody or IgM subtype could predict future unexplained recurrent miscarriages warrants a prospective study.


Asunto(s)
Aborto Habitual , Síndrome Antifosfolípido , Embarazo , Femenino , Humanos , Adolescente , Adulto Joven , Adulto , Protrombina , Estudios Retrospectivos , Fosfatidilserinas , Estudios Prospectivos , beta 2 Glicoproteína I , Anticuerpos Antifosfolípidos , Síndrome Antifosfolípido/diagnóstico , Anticuerpos Anticardiolipina , Inmunoglobulina G , Inmunoglobulina M
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