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1.
Ultrason Sonochem ; 107: 106946, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38852536

RESUMO

Low sensitivity octahydro-1,3,4,7-tetranitro-1,3,5,7-tetrazocine (HMX) has garnered significant attention from researchers due to its reduced shock sensitivity. However, the crystallization process poses challenges due to the high solidity and viscosity of the metastable α phase. Despite efforts to address this with additional energy sources like ultrasonic irradiation, prolonged exposure duration often results in small particle sizes, hindering the production of HMX with a consistent particle size distribution, thus limiting its applicability. To overcome these challenges, a method combining ultrasonic irradiation and trace H+ additive was proposed and investigated for their impact on the polymorphic transformation of HMX. The H+ additive was found to modify barriers, thus there was a lack of competitive driving force for the nucleation or growth of the metastable α form, thereby shortening the transformation pathway and duration. Moreover, the H+ additive significantly accelerated the nucleation rate of the ß form (67.7 orders of magnitude faster with 0.10 wt ‰ H+) and the growth rate of ß form HMX (5.8 orders of magnitude faster with 0.10 wt ‰ H+). While H+ additive alone was insufficient to induce spontaneous nucleation of the ß form, combining it with short-duration ultrasonic irradiation further promoted ß nucleation and shortened the polymorphic transformation duration (almost 20 orders of magnitude shorter). This rational approach led to effective control of the transformation process. The resulting low sensitivity HMX crystals exhibited varying mean sizes ranging from 20 to 340 µm, with purity exceeding 99.6 %, an apparent density greater than 1.8994 g/cm3, and few internal defects, fully meeting the requirements of low-sensitivity HMX, thus significantly expanding its potential applications. Our study sheds light on the mechanisms governing HMX polymorphic transformation in the presence of additives and ultrasonic irradiation, offering guidance for the rational control of this complex transformation.

2.
Appl Opt ; 63(10): 2710-2718, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568556

RESUMO

Aimed at the regional open-path detection of benzene (C 6 H 6) in the atmosphere, a power-modulated integrated path differential absorption (PM-IPDA) lidar is introduced and demonstrated. Two tunable interband cascade lasers (ICLs) with about 3.2 µm wavelength are utilized to generate the required PM optical signal. These two operation central wavelengths (CWs) of the PM-IPDA lidar are, respectively, 3236.6 and 3187.1 nm, which can mitigate the influence of significant gases such as H 2 O, C H 4, and HCl on the detection performance. In this work, the fast Fourier transform algorithm is used to retrieve the measured values with the time resolution of 0.1 s corresponding to 104 sampling bins at the sampling rate of 100 kSps/s. The modulated frequency of the PM-IPDA lidar is selected as 10 kHz by laboratory experiments. The slow fluctuation characteristic of the benzene absorption spectrum within the vicinity region of 3.2 µm reduces the impact of small wavelength fluctuations on the performance of PM-IPDA lidar, although a scheme modulated only the driving current causes wavelength fluctuations of ∼±0.2n m. These laboratory experiments also indicate the PM-IPDA lidar can reduce the error resulting from 1/f noise. Open-path observation experiments show that the detection limit is about 0.60m g⋅m -3 and that the PM-IPDA lidar can be used for the regional open-path real-time detection of benzene.

3.
ACS Appl Mater Interfaces ; 16(17): 22580-22592, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38634565

RESUMO

The application of high-performance rubber nanocomposites has attracted wide attention, but its development is limited by the imbalance of interface and network effects caused by fillers. Herein, an ultrastrong polymer nanocomposite is successfully designed by introducing a superhydrophobic and mesoporous silica aerogel (HSA) as the filler to poly(methyl vinyl phenyl) siloxane (PVMQ), which increased the PVMQ elongation at break (∼690.1%) by ∼9.3 times and the strength at break (∼6.6 MPa) by ∼24.3 times. Furthermore, HSA/PVMQ with a high dynamic storage modulus (G'0) of ∼12.2 MPa and high Payne effect (ΔG') of ∼9.4 MPa is simultaneously achieved, which is equivalent to 2-3 times that of commercial fumed silica reinforced PVMQ. The superior performance is attributed to the filler-rubber interfacial interaction and the robust filler-rubber entanglement network which is observed by scanning electron microscopy. When the HSA-PVMQ entanglement network is subjected to external stress, both the HSA and bound-PVMQ chains are synergistically involved in resisting structural evolution, resulting in the maximized energy dissipation and deformation resistance through the desorption of the polymer chain and the slip/interpenetrating of the exchange hydrogen bond pairs. Hence, highly aggregated nanoporous silica aerogels may soon be widely used in the application of reinforced silicone rubber or other polymers shortly.

4.
J Mol Biol ; : 168530, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38462130

RESUMO

Through an extensive literature survey, we have upgraded the Leaf Senescence Database (LSD v5.0; https://ngdc.cncb.ac.cn/lsd/), a curated repository of comprehensive senescence-associated genes (SAGs) and their corresponding mutants. Since its inception in 2010, LSD undergoes frequent updates to encompass the latest advances in leaf senescence research and its current version comprises a high-quality collection of 31,740 SAGs and 1,209 mutants from 148 species, which were manually searched based on robust experimental evidence and further categorized according to their functions in leaf senescence. Furthermore, LSD was greatly enriched with comprehensive annotations for the SAGs through meticulous curation using both manual and computational methods. In addition, it was equipped with user-friendly web interfaces that facilitate text queries, BLAST searches, and convenient download of SAG sequences for localized analysis. Users can effortlessly navigate the database to access a plethora of information, including literature references, mutants, phenotypes, multi-omics data, miRNA interactions, homologs in other plants, and cross-links to various databases. Taken together, the upgraded version of LSD stands as the most comprehensive and informative plant senescence-related database to date, incorporating the largest collection of SAGs and thus bearing great utility for a wide range of studies related to plant senescence.

5.
Bioact Mater ; 35: 564-576, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38469201

RESUMO

Rheumatoid arthritis (RA) is a severe autoimmune disease with symptoms including synovial inflammation, cartilage erosion, and bone loss in RA lesions, which eventually lead to joint deformity and function loss. Most current treatments fail to achieve satisfying therapeutic outcomes with some adverse effects. Extracellular vesicles derived from apoptotic cells (apoEVs) have emerged as important mediators in intercellular communication regulating diverse physiological and pathological processes. In this study, we investigated the therapeutic efficacy of macrophage-derived and osteoclast-derived apoEVs (Mφ-apoEVs and OC-apoEVs) on RA. The in vitro results showed that both Mφ-apoEVs and OC-apoEVs induced macrophage repolarization toward the anti-inflammatory M2 phenotype, promoted chondrocyte functions and chondrogenesis, and inhibited osteoclast formation and maturation. In addition, OC-apoEVs promoted osteogenic differentiation. The in vivo study on the CIA mouse model further demonstrated that apoEVs could couple various functions and exert synergistic effects on the joint with RA, as evidenced by the regression of synovial inflammation, the reversal of cartilage damage and bone erosion, and the preservation of joint structure. These findings demonstrated that Mφ-apoEVs and OC-apoEVs contributed to restoring the homeostasis of the overall microenvironment in the RA joint and highlighted their potential application as a promising alternative to treat RA.

6.
Appl Opt ; 63(5): 1210-1216, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38437299

RESUMO

Aimed at the stability of calibration coefficients in a general non-orthogonal retrieval algorithm (NRA) of pure rotational Raman lidars (PRRLs), an orthogonal retrieval algorithm (ORA) of atmospheric temperature profiles based on the orthogonal basis function is proposed. This algorithm eliminates the correlation between the calibration coefficients in the NRA to reduce the influence of the number of calibration points and the selection scheme on the calibration coefficients. In this paper, the stabilities of calibration coefficients in the NRA and ORA are compared and analyzed, and the data analysis for atmospheric temperature profiles with a time resolution of minute-level are given, based on the developed Cloud Precipitation Potential Evaluation (CPPV) lidar data and the parallel radiosonde temperature data. The analysis results show that coefficients of variation (CVs) of ORA calibration coefficients are one order of magnitude smaller than those of NRA coefficients. The mean deviation of the ORA retrieval results is roughly reduced by 16.1% compared with the NRA, and the root-mean-square deviation is roughly reduced by 15.0% compared with the NRA. Therefore, the temperature retrieval performance of the ORA is better than that of the NRA.

7.
Plant Physiol Biochem ; 207: 108399, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38277833

RESUMO

Non-coding RNAs (ncRNAs) are a special class of functional RNA molecules that are not translated into proteins. ncRNAs have emerged as pivotal regulators of diverse developmental processes in plants. Recent investigations have revealed the association of ncRNAs with the regulation of leaf senescence, a complex and tightly regulated developmental process. However, a comprehensive review of the involvement of ncRNAs in the regulation of leaf senescence is still lacking. This manuscript aims to summarize the molecular mechanisms underlying ncRNAs-mediated leaf senescence and the potential applications of ncRNAs to manipulate the onset and progression of leaf senescence. Various classes of ncRNAs, including microRNAs (miRNAs), small interfering RNAs (siRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), are discussed in terms of their regulatory mechanisms in leaf senescence. Furthermore, we explore the interactions between ncRNA and the key regulators of senescence, including transcription factors as well as core components in phytohormone signaling pathways. We also discuss the possible challenges and approaches related to ncRNA-mediated leaf senescence. This review contributes to a further understanding of the intricate regulatory network involving ncRNAs in leaf senescence.


Assuntos
MicroRNAs , RNA Longo não Codificante , Senescência Vegetal , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Interferente Pequeno
9.
Nat Mater ; 22(7): 888-894, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37169976

RESUMO

Membranes with ultrahigh permeance and practical selectivity could greatly decrease the cost of difficult industrial gas separations, such as CH4/N2 separation. Advanced membranes made from porous materials, such as metal-organic frameworks, can achieve a good gas separation performance, although they are typically formed on support layers or mixed with polymeric matrices, placing limitations on gas permeance. Here an amorphous glass foam, agfZIF-62, wherein a, g and f denote amorphous, glass and foam, respectively, was synthesized by a polymer-thermal-decomposition-assisted melting strategy, starting from a crystalline zeolitic imidazolate framework, ZIF-62. The thermal decomposition of incorporated low-molecular-weight polyethyleneimine evolves CO2, NH3 and H2O gases, creating a large number and variety of pores. This greatly increases pore interconnectivity but maintains the crystalline ZIF-62 ultramicropores, allowing ultrahigh gas permeance and good selectivity. A self-supported circular agfZIF-62 with a thickness of 200-330 µm and area of 8.55 cm2 was used for membrane separation. The membranes perform well, showing a CH4 permeance of 30,000-50,000 gas permeance units, approximately two orders of magnitude higher than that of other reported membranes, with good CH4/N2 selectivity (4-6).


Assuntos
Gases , Estruturas Metalorgânicas , Peso Molecular , Polietilenoimina , Polímeros
10.
Ecotoxicol Environ Saf ; 256: 114874, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37054469

RESUMO

Lead (Pb), cadmium (Cd) and total mercury (THg) are toxic heavy metals (THMs) that are widely present in the environment and can cause substantial health problems. However, previous risk assessment studies have rarely focused on the elderly population and have usually targeted a single heavy metal, which might underestimate the long-term accumulative and synergistic effects of THMs in humans. Based on the food frequency questionnaire and inductively coupled plasma mass spectrometry, this study assessed external and internal exposures to Pb, Cd and THg in 1747 elderly people in Shanghai. Probabilistic risk assessment with the relative potential factor (RPF) model was used to assess the neurotoxicity and nephrotoxicity risks of combined THMs exposures. The mean external exposures of Pb, Cd and THg in Shanghai elderly were 46.8, 27.2 and 4.9 µg/day, respectively. Plant-based foods are the main source of Pb and THg exposure, while Cd is mainly from animal-based foods. The mean concentrations of Pb, Cd and THg were 23.3, 1.1 and 2.3 µg/L in the whole blood, and 6.2, 1.0 and 2.0 µg/L in the morning urine, respectively. Combined exposure to THMs leading to 10.0 % and 7.1 % of Shanghai elderly at risk of neurotoxicity and nephrotoxicity. The results of this study have important implications for understanding the profiles of Pb, Cd and THg exposure in the elderly living in Shanghai and provide data support for risk assessment and control of nephrotoxicity and neurotoxicity from combined THMs exposure in the elderly.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Mercúrio , Metais Pesados , Síndromes Neurotóxicas , Animais , Humanos , Idoso , Cádmio/toxicidade , Mercúrio/análise , Chumbo/análise , China , Metais Pesados/análise , Intoxicação por Metais Pesados , Medição de Risco
11.
Langmuir ; 39(9): 3391-3399, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36821086

RESUMO

Ultrafine explosives show high safety and reliable initiation and have been widely used in aerospace, military, and industrial systems. The outstanding performance of ultrafine explosives is largely given by the unique void defects according to the simulation results. However, the structures and effects of internal nano-voids in ultrafine explosive particles have been rarely investigated experimentally. In this work, contrast-variation small angle X-ray scattering was verified to reliably measure the structures of internal nano-voids in ultrafine explosive 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) and 2,2',4,4',6,6'-hexanitro diphenylethylene (HNS). The size of nano-voids is around 10 nm, and the estimated number of nano-voids in a single particle is considerable. Moreover, the thermal stability of ultrafine LLM-105 was improved via changing the structures of nano-voids. This work provides a methodology for the study of nano-void defects in ultrafine organic particles and may pave the path to enhance the performance of ultrafine explosives via defect engineering.

12.
Langmuir ; 38(45): 13833-13840, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36322166

RESUMO

Metal-oxide-based chemiresistive hydrogen sensors exhibit high sensitivity, long-term stability, and low cost and have been extensively applied in safety monitoring of H2. However, the sensing performances are dramatically affected by the water vapor, resulting in reduced response value and increased response/recovery time. To improve the anti-humidity property of sensors, coating the breathable and hydrophobic membrane on the surface of the sensing film is an effective strategy. In this work, the poly[4,5-difluoro-2,2-bis(trifluoromethyl)-1,3-dioxole-co-tetrafluoroethylene] (Teflon AF-2400) was dip-coated on the surface of SnO2 in a commercial hydrogen sensor (TGS2615) as a breathable and hydrophobic membrane. For safety, He instead of H2 was used to test the gas permeability of membranes. The Teflon membrane shows a high He permeability of up to 40,700 Barrer and an excellent He/H2O selectivity of 99. Moreover, Teflon shows high processability to form a defect-free coating on the rough surface of the sensing film and high chemical stability under the operando condition of the sensor. Thus, the Teflon-modified sensor possesses excellent selectivity with a value of 5, and the resistance is stable at 10,554 ± 3% Ω for 20 days in 80% RH. The modified sensor shows an improved anti-humidity property with a 75% response to 200 ppm H2 at 80% RH and has a low coefficient of variation value of 7.23% that shows advances than other reported sensors modified by coatings. The commercially available Teflon and the simple coating technology make the strategy easily scale up and show promising applications.

13.
Int Immunopharmacol ; 113(Pt A): 109290, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36252498

RESUMO

There are two distinct phenotypes of activated microglia, pro-inflammatory M1 and anti-inflammatory M2. Accumulating evidence indicates that shifting the microglial polarization from M1 to M2 is a potential strategy for the treatment of neuroinflammation-associated brain diseases, including ischemic stroke. Cycloastragenol (CAG) is a hydrolysis product of astragaloside IV, the major active component of Astragalus radix. We have previously demonstrated that CAG has anti-inflammatory effect in a mouse model of ischemic stroke. This study investigated the effect of CAG on the phenotype polarization of microglia in lipopolysaccharide (LPS)-stimulated BV-2 mouse microglial cells and ischemic stroke mice. In LPS-treated BV-2 cells, we found that CAG significantly reduced the expression of M1 markers, including pro-inflammatory cytokines and enzymes. In contrast, CAG promoted the expression of M2 markers, including anti-inflammatory cytokines and growth factor. In addition, CAG inhibited the activation of nuclear factor-κB (NF-κB) and enhanced the activation of nuclear factor E2-related factor 2 (Nrf2) and the expression of its downstream heme oxygenase-1 (HO-1). Furthermore, CAG also inhibited levels of M1 markers, promoted those of M2 markers, and enhanced Nrf2 activation and HO-1 expression in ischemic mouse brain. Importantly, the effect of CAG on M2 markers, but not M1 markers, was reversed by Nrf2 siRNA in LPS-stimulated BV-2 cells. Together, our results suggested that CAG promoted microglial M2 and suppressed M1 polarization through activating Nrf2 and inhibiting NF-κB, respectively, in LPS-stimulated BV-2 cells and ischemic mouse brain. CAG is a promising candidate for the treatment of neuroinflammation-related diseases, including ischemic stroke.


Assuntos
AVC Isquêmico , Sapogeninas , Animais , Camundongos , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Lipopolissacarídeos , Microglia , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Sapogeninas/farmacologia
14.
Materials (Basel) ; 15(19)2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36234175

RESUMO

The atomic scale local structures affect the initiation performance of ultra-fine explosives according to the stimulation results of hot spot formation. However, the experimental characterization of local structures in ultra-fine explosives has been rarely reported, due to the difficulty in application of characterization methods having both high resolution in and small damage to unstable organic explosive materials. In this work, X-ray total scattering was explored to investigate the atomic scale local distortion of two widely applicable ultra-fine explosives, LLM-105 and HNS. The experimental spectra of atomic pair distribution function (PDF) derived from scattering results were fitted by assuming rigid ring structures in molecules. The effects of grain refinement and thermal aging on the atomic scale local structure were investigated, and the changes in both the length of covalent bonds have been identified. Results indicate that by decreasing the particle size of LLM-105 and HNS from hundreds of microns to hundreds of nanometers, the crystal structures remain, whereas the molecular configuration slightly changes and the degree of structural disorder increases. For example, the average length of covalent bonds in LLM-105 reduces from 1.25 Å to 1.15 Å, whereas that in HNS increases from 1.25 Å to 1.30 Å, which is possibly related to the incomplete crystallization process and internal stress. After thermal aging of ultra-fine LLM-105 and HNS, the degree of structural disorder decreases, and the distortion in molecules formed in the synthesis process gradually healed. The average length of covalent bonds in LLM-105 increases from 1.15 Å to 1.27 Å, whereas that in HNS reduces from 1.30 Å to 1.20 Å. The possible reason is that the atomic vibration in the molecule intensifies during the heat aging treatment, and the internal stress was released through changes in molecular configuration, and thus the atomic scale distortion gradually heals. The characterization method and findings in local structures obtained in this work may pave the path to deeply understand the relationship between the defects and performance of ultra-fine explosives.

15.
Environ Pollut ; 312: 120026, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36029907

RESUMO

Mercury (Hg) is a widespread heavy metal causing various damages to health, while insufficient studies assessed its exposure risk across China. This study explored concentrations in food items and dietary exposure risks across China by comprehensively analyzing the researches on total Hg (THg) in eight food items and methylmercury (MeHg) in aquatic foods published between 1980 and 2021. According to the included 695 studies, the average THg concentration in all food items was 0.033 mg/kg (ranging from 0.004 to 0.185 mg/kg), with the highest concentration in edible fungi. The average daily dietary THg exposure from all foods was 12.9 µg/day. Plant-based foods accounted for 62.7% of the dietary THg exposure. Cereals and vegetables were the primary source of THg exposure. The MeHg concentration in aquatic foods was 0.08 mg/kg, and the average dietary exposure was 3.8 µg/day. Monte Carlo simulations of the dietary exposure risk assessment of THg and MeHg showed that approximately 6.4 and 7.0% of residents exceeded the health-based guidance value set by the European Food Safety Authority, with higher exposure risk in Southwest and South China. The nationwide target hazard quotient index of THg was greater than 1, suggesting that the non-carcinogenic risk of dietary exposure to THg needed further concern. In summary, this study has a comprehensive understanding of dietary Hg exposure risks across China, which provide a data basis for Hg exposure risk assessment and policy formulation.


Assuntos
Mercúrio , Metais Pesados , Compostos de Metilmercúrio , China , Exposição Dietética , Monitoramento Ambiental , Contaminação de Alimentos/análise , Mercúrio/análise , Compostos de Metilmercúrio/análise , Medição de Risco
16.
J Colloid Interface Sci ; 628(Pt A): 426-436, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-35932679

RESUMO

Strongly hydrogen-bonded compounds such as 1,3,5-triamino-2,4,6­trinitrobenzene (TATB, an important insensitive high explosive) have excellent stability, but poor solubilities to limit their recrystallization, purification and recycling. In this study, core-shell clusters based on symmetrical tetra-n-alkylammonium [TTA]+ are designed to provide an inner cavity to incorporate TATB, and thus the clusters can separate TATB from original hydrogen-bonded networks to increase largely the solubility. Based on this design, deep eutectic solvents (DESs) based on [TTA]+ cations are first developed to yield self-assembled core-shell clusters for solubilizing TATB. Ninety-nine DESs based on [TTA]+ were prepared by combining with halide ions and hydrogen bond donors, and TATB's solubility increases with the formation of core-shell clusters. Tetrabutyl ammonium ([TBA]+ )-based DES (CS-1) displays excellent dissolution toward TATB. Room-temperature solubility of TATB in CS-1 with 32.88 mg/mL is about 10 times higher than recently reported ionic liquids and approximately 470 times higher than DMSO. Compared to traditional solvents, CS-1 shows economical and high dissolution ability toward TATB. The dissolution mechanism is demonstrated by experimental characterizations and theoretical calculations. After forming Zundel-type complexes between TATB and F-, the complexes as the core are surrounded by [TBA]+ as the shell to yield core-shell clusters through self-assembly of electrostatic interaction.

17.
Molecules ; 27(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35744992

RESUMO

Nano-scale crystal defects extremely affect the security and reliability of explosive charges of weapons. In this work, the nano-scale crystal defects of 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) single crystals were characterized by two-dimension SAXS. Deducing from the changes of SAXS pattern with sample stage rotating, we firstly found the parallel lamellar nano-scale defects in both RDX and HMX single crystals. Further analysis shows that the average diameter and thickness of nano-scale lamellar defects for RDX single crystal are 66.4 nm and 19.3 nm, respectively. The results of X-ray diffraction (XRD) indicate that the lamellar nano-scale defects distribute along the (001) in RDX and the (011) in HMX, which are verified to be the crystal planes with the lowest binding energy by the theoretical calculation.

18.
Cell Biochem Biophys ; 80(2): 403-414, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35171434

RESUMO

Porcine growth hormone (pGH) has many important biological functions and roles, and the biological activity of pGH is closely related with its cell behavior and characteristics. However, so far, the behavior of pGH in swine testicular cell remains unclear. For this, in the current work, the swine testicular cell line (ST) was used as an in vitro model, and CLSM (Confocal laser scanning microscope), IFA (Indirect immunofluorescence assay), FCM (Flow cytometry) and WB (Western-blotting) were used to explore the pGH's cell behivior and function, and the results showed that pGH and GHR could internalize into ST cell and transported to the nucleus. Furthermore, we studied the internalization kinetics of pGH and GHR on ST cell, and found that pGH and GHR internalizes into ST cell in a time-dependent manner. More importantly, we also investigated the potential molecular functions of pGH-GHR after it entered into the cell nuclei. The results indicated that nuclear-localized GHR could participate in cell proliferation by regulating the signal intensity of STAT5. In summary, our current research shows that the nuclear-localized pGH-GHR participates in the cell proliferation of ST cell, which lays a solid foundation for further research on the regulatory effect of pGH on testicular tissue.


Assuntos
Hormônio do Crescimento , Receptores da Somatotropina , Animais , Núcleo Celular/metabolismo , Hormônio do Crescimento/metabolismo , Hormônio do Crescimento/farmacologia , Hepatócitos/metabolismo , Receptores da Somatotropina/metabolismo , Transdução de Sinais , Suínos
19.
Int Immunopharmacol ; 105: 108569, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35091336

RESUMO

Post-ischemic peripheral immunosuppression increases vulnerability to infection which is a common complication and worsens outcome in ischemic stroke patients. Hypothalamic-pituitary-adrenal (HPA) axis plays a key role in post-ischemic immunosuppression. Astragaloside IV (ASIV), isolated from Astragalus membranaceus, possesses immunomodulatory and neuroprotective effects against cerebral ischemic injury. This study investigated the effect of ASIV on cerebral ischemia-induced peripheral immunosuppression and the underlying mechanism in a mouse model of middle cerebral artery occlusion (MCAO). Our results showed that ASIV significantly prevented the atrophy of spleen and the reduction of splenic cell count. Meanwhile, ASIV preserved cell numbers of splenic NK, T, and B cells in the spleen. ASIV also suppressed apoptosis of splenic cells and preserved their proliferation ability. In addition, ASIV robustly reduced the mRNA expression of TNF-α, IL-1ß, IL-6 and CRH in the hypothalamus, as well as the enlargement of adrenal gland and the increase of corticosterone in blood, indicating the inhibition of HPA axis by ASIV. Furthermore, ASIV did not enhance the effect of HPA inhibition on reducing splenic atrophy and preserving splenic NK, T, and B cell numbers in MCAO mice. Of note, ASIV did not attenuate splenic cell apoptosis induced by prednisolone, suggesting that ASIV may ameliorate splenic apoptosis through reducing peripheral glucocorticoid level. Our findings demonstrate that ASIV ameliorates post-ischemic peripheral immunosuppression through inhibiting the activation of HPA axis and targeting HPA activation to ameliorate peripheral immunosuppression may be a promising strategy to improve clinical outcomes of ischemic stroke.


Assuntos
Saponinas , Triterpenos , Animais , Humanos , Sistema Hipotálamo-Hipofisário , Terapia de Imunossupressão , Infarto da Artéria Cerebral Média/tratamento farmacológico , Camundongos , Sistema Hipófise-Suprarrenal , Saponinas/farmacologia , Saponinas/uso terapêutico , Triterpenos/farmacologia , Triterpenos/uso terapêutico
20.
Artigo em Inglês | MEDLINE | ID: mdl-34899952

RESUMO

OBJECTIVE: To study the clinical efficacy of integrated traditional Chinese medicine (TCM) and Western medicine (WM) in treating endometrial cancer and the influence on ultrasound, magnetic resonance imaging (MRI), tumor markers, human epididymis protein 4 (HE4) and carbohydrate antigen 125 (CA125). METHOD: A total of 152 cases of patients with endometrial carcinoma were randomly divided into two groups: the TCM + WM group and the WM group. The WM group was treated with megestrol acetate tablets, and the TCM + WM group was treated with Radix Astragali injection on the basis of the control group. The levels of inflammatory factors, HE4 and CA125 in serum, were detected using enzyme-linked immunosorbent assay (ELISA) or radioimmunoassay. The characteristics of ultrasound images and MRI images were observed and recorded. Toxicity, side effects, and the 3-year cumulative survival rate after treatment were assessed. RESULTS: After treatment, the levels of interleukin-4 (IL-4), tumor necrosis factor-alpha (TNF-α), and high-sensitivity C-reactive protein (hs-CRP) in both groups decreased, and the decrease in the TCM + WM group was more obvious than that in the WM group. There were statistically significant differences between the two groups in lesion shape, boundary, blood flow signal, lesion diameter, resistance index (RI), echo, intima thickness, and muscle layer infiltration from transvaginal ultrasound images after treatment. The diameter, echo, boundary, shape, composition, and enhancement degree of lesions between the two groups have a significant difference. Moreover, the levels of serum HE4 and CA125 in both groups decreased after treatment, and the decrease in the TCM + WM group was more obvious than that in the WM group. There were statistically significant differences between the two groups in the occurrence of myelosuppression, abnormal liver function, decreased platelet number, gastrointestinal reactions, leukopenia, and cardiotoxicity. After three years of follow-up, the cumulative survival rate of the TCM + WM group was 76.32%, and the cumulative survival rate of the WM group was 57.89%. CONCLUSION: Radix Astragali injection combined with megestrol acetate tablets has obvious therapeutic effects against endometrial cancer. Through vaginal ultrasonography and MRI, it can significantly improve the size, shape, and blood flow signals of patients' lesions, reduce the level of serum inflammatory factors and tumor markers HE4 and CA125, reduce the incidence of toxic and side reactions, improve the patient's immunity, improve the patient's condition significantly, and prolong the survival time of patients.

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