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1.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3591-3599, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39041131

RESUMO

This study investigated the immunological mechanisms of Ermiao powder in the treatment of rheumatoid arthritis rats through the alpha 7 nicotinic acetylcholine receptor(α7nAChR)-Janus kinases 2(JAK2)/signal transducer and activator of transcription 3(STAT3) signaling pathway. A total of 56 female Wistar rats were randomly divided into the normal group(HG, n=8), collagen-induced arthritis(CIA) model group(CM, n=8), vagotomy group(VA, n=8), sham group(SH, n=8), Ermiao Powder treatment model group(EM, n=8), Ermiao Powder treatment for vagotomy group(EV, n=8) and Ermiao Powder treatment for sham group(ES, n=8). Following the establishment of CIA models in all groups except the HG group, the rats underwent unilateral vagotomy and sham operation(only the vagus nerve was separated). Drug treatment was started 7 days after surgery and continued for 35 days. The body weight and joints of rats were recorded, the pathological changes of the spleen of rats were observed, the contents of interleukin-6(IL-6), interleukin-1ß(IL-1ß) and tumor necrosis factor-α(TNF-α) in serum were detected by enzyme-linked immunosorbent assay(ELISA), and the mRNA and protein expression of α7nAChR-JAK2/STAT3 pathway core genes in spleen were detected by qRT-PCR, Western blot and immunohistochemistry. RESULTS:: showed that CM group(compared with HG group) and VA group(compared with CM group and SH group) had significantly decreased body weight(P<0.05, P<0.01), increased arthritis score(P<0.05, P<0.01), swollen ankle joints with deformity, and increased and enlarged lymph nodes in the spleen. There were also notable increases in the serum levels of IL-6, IL-1ß and TNF-α(P<0.05, P<0.01), and in the mRNA expressions of JAK2 and STAT3 in the spleen(P<0.05, P<0.01). The protein levels of phosphorylated JAK2(p-JAK2)/JAK2 and phospho-STAT3(p-STAT3)/STAT3 were significantly increased(P<0.05, P<0.01), and the number of JAK2, p-JAK2, STAT3 and p-STAT3 cells increased(P<0.05, P<0.01). EM group(compared with CM group) and ES group(compared with SH group) exhibited significantly increased body weight(P<0.01), decreased arthritis scores(P<0.05, P<0.01), reduced swelling of ankle joint, and decreased number and volume of lymph nodes in the spleen. Furthermore, serum levels of IL-6, IL-1ß, and TNF-α decreased(P<0.05, P<0.01), the mRNA expression of JAK2 and STAT3 in spleen decreased(P<0.05, P<0.01), the protein levels of p-JAK2/JAK2 and p-STAT3/STAT3 decreased(P<0.05, P<0.01), and the number of JAK2, p-JAK2, STAT3 and p-STAT3 cells decreased(P<0.05, P<0.01), whereas the mRNA and protein expressions of α7nAChR were significantly increased(P<0.01). Compared with the VA group, there was no significant differences in weight gain and arthritis scores in the EV group. The number of lymph nodes in the spleen was not significantly reduced and the volume was still large, suggesting the inflammation was not significantly improved. The serum levels of IL-6, IL-1ß and TNF-α were not significantly different, and there were no significant differences in α7nAChR, JAK2, and STAT3 mRNA expression in the spleen. The protein expression levels of p-JAK2/JAK2 and α7nAChR in spleen were lower(P<0.05, P<0.01), while p-STAT3/STAT3 protein expression was not significantly different. Besides, the two groups had no significant difference in the number of JAK2, p-JAK2, STAT3, and p-STAT3 cells. The results suggested that unilateral vagotomy promoted the increase of phosphorylated JAK2 and STAT3 expressions and exacerbated inflammation. In contrast, Ermiao Powder alleviated the inflammation in rheumatoid arthritis rats by activating the α7nAChR-mediated JAK2/STAT3 pathway through the vagus nerve, suggesting that the α7nAchR-JAK2/STAT3 pathway may be a potential target for the treatment of rheumatoid arthritis.


Assuntos
Artrite Experimental , Medicamentos de Ervas Chinesas , Janus Quinase 2 , Ratos Wistar , Fator de Transcrição STAT3 , Transdução de Sinais , Receptor Nicotínico de Acetilcolina alfa7 , Animais , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , Janus Quinase 2/metabolismo , Janus Quinase 2/genética , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Ratos , Feminino , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Artrite Experimental/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Pós , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Humanos , Interleucina-6/genética
2.
Phytochemistry ; 225: 114196, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38936529

RESUMO

One previously undescribed xanthanolide sesquiterpene dimer pungiolide P (1), possessing an unprecedented scaffold with a 5/7/5/7/5 ring system skeleton and its intermediate pungiolide Q (2), ten xanthanolide sesquiterpenes (3-12), two eudesmene sesquiterpene derivatives (13-14), one phenylpropionic acid derivative (15), together with eleven known compounds (16-26) were obtained from the fruits of Xanthium italicum Moretti. A possible biosynthetic pathway for pungiolide P (1) was also proposed, which was supported by its bio-synthetic intermediate (2). Compounds 1, 4-5, 18-21, and 25 exhibited cytotoxic activity against a variety of human cancer cell lines. Furthermore, compounds 1, 4-5, could cause blockage of the cell cycle in the G2/M phase and induce apoptosis in H460 cells. Notably, pungiolide P (1) exhibited significantly superior cytotoxicity compared to previously reported compounds, providing valuable insights for natural anti-tumor sources.


Assuntos
Antineoplásicos Fitogênicos , Apoptose , Ensaios de Seleção de Medicamentos Antitumorais , Frutas , Sesquiterpenos , Xanthium , Xanthium/química , Humanos , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Frutas/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos
3.
Phys Rev E ; 109(1-2): 015208, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38366504

RESUMO

Quasimonoenergetic GeV-scale protons are predicted to be efficiently generated via radiation pressure acceleration (RPA) when the foil thickness is matched with the laser intensity, e.g., L_{mat} of several nm to 100 nm for 10^{19}-10^{22}Wcm^{-2} available in laboratory. However, nonmonoenergetic protons with much lower energies than predicted were usually observed in RPA experiments because of too small foil thickness which cannot support insufficient laser contrast and foil surface roughness. Besides the technical problems, we here find that there is an upper-limit thickness L_{up} derived from the requirement that the laser energy should dominate over the ion source energy in the effective laser-proton interaction zone, and L_{up} is lower than L_{mat} with the intensity below 10^{22}Wcm^{-2}, which causes inefficient or unsteady RPA. As the intensity is enhanced to ≥10^{23}Wcm^{-2} provided by 10-100 PW laser facilities, L_{up} can significantly exceed L_{mat}, and therefore RPA becomes efficient. In this regime, L_{mat} acts as a lower-limit thickness for efficient RPA, so the matching thickness can be extended to a continuous range from L_{mat} to L_{up}; the range can reach micrometers, within which foil thickness is adjustable. This makes RPA steady and meanwhile the above technical problems can be overcome. Particle-in-cell simulation shows that multi-GeV quasimonoenergetic proton beams can be steadily generated and the fluctuation of the energy peaks and the energy conversation efficiency remains stable although the thickness is taken in a larger range with increasing intensity. This work predicts that near future RPA experiments with 10-100 PW facilities will enter a new regime with a large range of usable foil thicknesses that can be adjusted to the interaction conditions for steady acceleration.

4.
Orthop Surg ; 14(8): 1873-1883, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35819089

RESUMO

OBJECTIVE: To assess a safe surgical approach for intertransverse process lower thoracic intervertebral body fusion (ITIF) based on measurements from enhanced three-dimensional CT reconstruction, cadaver simulated operation, and patient operation. METHODS: Enhanced three-dimensional CT image reconstruction was performed for 20 healthy volunteers on thoracic segments T8-T12. The length of the transverse process (LTP), distance between the upper and lower transverse processes (DULTP), remote distance of the transverse process (RDTP), height of the extraforaminal intervertebral space (HEIS), and oblique diameter of the intervertebral space (ODIS) were measured and recorded. The blood vessels of the intertransverse lower thoracic region were observed, and their internal diameters were measured. The rib-intervertebral space relationship for T10/11 and T11/12 was measured in 104 patients of the thoracic skeleton. Then, based on the data from the CT measurements, simulated surgery was performed on six human cadavers at the T11/12 level. An ankylosing spondylitis (AS) patient with a fracture of the T10/11 level was eventually operated on with the ITIF technique. RESULTS: No significant difference was found between the lengths of the left and right thoracic transverse processes. The relationship of the values of the LTP and RDTP for the measured vertebrae were found to be as follows:T8 > T9 > T10 > T11 > T12. For HEIS and DULTP, T8-9 < T9-10 < T10-11 < T11-12. The results for the ODIS were as follows: T8-T9 < T9-T10 < T10-T11 < T11-T12. The blood vessel inner diameter of T11-12 was less than that of T10-11, while there was no significant difference between the diameters for T8-9 and T11-12. Almost half of the volunteer's T10/11 intervertebral spaces were covered posteriorly by the 11th rib (45.19% on left and 41.35% on right), while for most patients, the T11/12 intervertebral space was not covered by the 12th rib (98.08%). According to the cadaver experiments, intervertebral bone grafting and ipsilateral pedicle screw fixation were performed to simulate the operation. One patient with a combined AS and T10/11 fracture was then operated on with the ITIF technique and followed up for 3 years with satisfactory results. CONCLUSION: As verified by 3D CT reconstruction measurements, cadaver simulation surgery and patient operation with follow-up, the intertransverse process approach for some T10/T11 and almost all T11/T12 segments is a safe surgical pathway for operations such as ITIF, fracture bone grafting, clearance of focal lesions.


Assuntos
Parafusos Pediculares , Espondilite Anquilosante , Transplante Ósseo , Cadáver , Humanos , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia
5.
Transl Androl Urol ; 9(3): 1244-1251, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32676407

RESUMO

BACKGROUND: The treatment of ketamine-induced bladder contractures remains poorly studied. We therefore evaluated the efficacy of cystectasia with a sodium hyaluronate balanced solution in this kind of bladder contracture. METHODS: Eighteen patients presenting with ketamine-induced bladder contracture between July 2010 and February 2018 were selected and analysed. Ketamine was discontinued in all patients, who were then treated with weekly cystectasia (0.09% sodium hyaluronate balanced solution) 3 times. The volume of the first perfusion was twice the preoperatively measured bladder capacity, and the volume of the subsequent two perfusions was increased by 100 mL each time. The Pelvic Pain and Urgency/Frequency (PUF) symptom score, O'Leary-Sant Interstitial Cystitis (IC) Symptom Index (ICSI), IC Problem Index (ICPI), Quality of Life (QOL) score, and bladder capacity were recorded before surgery and 3 and 12 months after the 3rd expansion. RESULTS: No significant complications were observed during the 3 expansions. Fourteen patients completed the full follow-up schedule. Preoperatively and at the 3- and 12-month follow-up evaluations performed after the 3rd expansion, the PUF symptom scores were 20.4±3.6, 11.5±3.1, and 13.2±3.3, respectively; the mean ICSI was 13.6±2.8, 7.7±2.3, and 8.2±2.5, respectively; the mean ICPI was 10.6±2.6, 7.3±2.1, and 7.7±2.5, respectively; and the mean QOL scores were 6.0±0, 2.1±0.5, and 2.7±0.8, respectively; and the mean bladder catheter volume was 83±27, 234±56, and 228±52 mL, respectively. There were significant differences between all preoperative and postoperative values. CONCLUSIONS: Cystectasia with a sodium hyaluronate balanced solution is an effective treatment modality for ketamine-induced bladder contracture.

6.
Zhongguo Zhong Yao Za Zhi ; 45(3): 683-688, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237529

RESUMO

It is reported that dihydroartemisinin could reduce the expression of phosphorylated adhesion kinase and matrix metalloproteinase-2, inhibit the growth, migration and invasion of ovarian cancer cells, promote the formation of Treg cells through TGF-beta/Smad signaling pathway, and play an immunosuppressive role; dihydroartemisinin could also inhibit the growth of lung cancer cells by inhibiting the expression of vascular endothelial growth factor(VEGF) receptor KDR. However, there are few studies on dihydroartemisinin in hepatocellular carcinoma cells. In order to preliminarily explore the effect of dihydroartemisinin on invasion and metastasis of hepatocellular carcinoma cells, CCK-8 method and crystal violet staining were used to detect the effect of dihydroartemisinin on the growth of hepatocellular carcinoma cell 7402 and highly metastatic hepatocellular carcinoma cell MHCC97 H. The effects of dihydroartemisinin on the invasion and metastasis of hepatocellular carcinoma cell 7402 and highly metastatic hepatocellular carcinoma cell MHCC97 H were studied by using cell wound healing and Transwell. Western blot was used to detect the protein expression of epidermal growth factor receptor(EGFR) and its downstream signaling pathway in cells treated with dihydroartemisinin for 48 hours. The results showed that dihydroartemisinin could inhibit the growth of hepatocellular carcinoma cell 7402 and highly metastatic hepatocellular carcinoma cell MHCC97 H at 25 µmol·L~(-1). As compared with the control group, the number of cell clones was significantly reduced, and the ability of cell migration and invasion was weakened. Western blot results showed that as compared with the control group, dihydroartemisinin group could down-regulate the protein expression of EGFR and its downstream signaling pathways p-AKT, p-ERK, N-cadherin, Snail and Slug, and up-regulate the expression of E-cadherin protein, thus affecting the migration, invasion and metastasis of hepatocellular carcinoma cells 7402 and MHCC97 H.


Assuntos
Artemisininas/farmacologia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Invasividade Neoplásica , Metástase Neoplásica , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular , Receptores ErbB/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Transdução de Sinais
7.
Huan Jing Ke Xue ; 40(12): 5524-5530, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854625

RESUMO

The selenium in the soil of Enshi, Hubei Province, is very rich, but there is also a certain degree of cadmium pollution risk. To scientifically utilize selenium-rich resources, a typical high-selenium and high-cadmium area in Shashi Township, Enshi City was selected as the research object. Combined with the corn cadmium selenium absorption model, a land safety zoning method was proposed. Comparing the health effects of selenium with the results of land safety zoning, it was found that the antagonism of selenium on cadmium can reduce the area of strict control of agricultural areas, and improve land use efficiency. Combined with the characteristics of cadmium and selenium in various crops in the study area, it is recommended for priority protection areas and safe-use areas to vigorously develop selenium-enriched agricultural products, and grow corn and tea in the structural adjustment area.


Assuntos
Agricultura , Cádmio , Selênio , Solo , Zea mays
8.
Proc Natl Acad Sci U S A ; 115(40): 9911-9916, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30224456

RESUMO

Even though high-quality X- and gamma rays with photon energy below mega-electron volt (MeV) are available from large-scale X-ray free electron lasers and synchrotron radiation facilities, it remains a great challenge to generate bright gamma rays over 10 MeV. Recently, gamma rays with energies up to the MeV level were observed in Compton scattering experiments based on laser wakefield accelerators, but the yield efficiency was as low as [Formula: see text], owing to low charge of the electron beam. Here, we propose a scheme to efficiently generate gamma rays of hundreds of MeV from submicrometer wires irradiated by petawatt lasers, where electron accelerating and wiggling are achieved simultaneously. The wiggling is caused by the quasistatic electric and magnetic fields induced around the wire surface, and these are so high that even quantum electrodynamics (QED) effects become significant for gamma-ray generation, although the driving lasers are only at the petawatt level. Our full 3D simulations show that directional, ultrabright gamma rays are generated, containing [Formula: see text] photons between 5 and 500 MeV within a 10-fs duration. The brilliance, up to [Formula: see text] photons [Formula: see text] per 0.1% bandwidth at an average photon energy of 20 MeV, is second only to X-ray free electron lasers, while the photon energy is 3 orders of magnitude higher than the latter. In addition, the gamma ray yield efficiency approaches 10%-that is, 5 orders of magnitude higher than the Compton scattering based on laser wakefield accelerators. Such high-energy, ultrabright, femtosecond-duration gamma rays may find applications in nuclear photonics, radiotherapy, and laboratory astrophysics.

9.
Phys Rev Lett ; 116(20): 205003, 2016 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-27258873

RESUMO

Coherent transition radiation in the terahertz (THz) region with energies of sub-mJ/pulse has been demonstrated by relativistic laser-driven electron beams crossing the solid-vacuum boundary. Targets including mass-limited foils and layered metal-plastic targets are used to verify the radiation mechanism and characterize the radiation properties. Observations of THz emissions as a function of target parameters agree well with the formation-zone and diffraction model of transition radiation. Particle-in-cell simulations also well reproduce the observed characteristics of THz emissions. The present THz transition radiation enables not only a potential tabletop brilliant THz source, but also a novel noninvasive diagnostic for fast electron generation and transport in laser-plasma interactions.

10.
Opt Express ; 24(4): 4010-21, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-26907053

RESUMO

We report a systematic study on backward terahertz (THz) radiation generation from laser-solid interactions by changing a variety of laser/plasma parameters. We demonstrate a high-energy (with an energy flux density reaching 80 µJ/sr), broadband (>10 THz) plasma-based radiation source. The radiation energy is mainly distributed either in the >10 THz or <3 THz regions. A radial surface current formed by the lateral transport of low-energy electrons (LEE) is believed to be responsible for the radiation in the high-THz region (>10 THz), while high-energy surface fast electrons (SFE) accelerated along the target surface mainly contribute to lower frequency (<3 THz) radiation. The unifying explanation could be applied to backward THz radiation generation from solid targets with presence of relative small preplasmas.

11.
Opt Express ; 22(10): 11797-803, 2014 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-24921301

RESUMO

The interaction of 100-fs laser pulses with solid targets at laser intensities 10(16)-10(18)W/cm(2) has been investigated experimentally by simultaneous measurements of terahertz (THz) and second harmonic signals. THz yield at the front side of the target, which rises from the self-organized transient electron currents along the target surface, is found scaling linearly with the laser intensity basically. Measurements of specularly reflected light spectrum show clear evidence of resonance absorption. The positive effects of resonance absorption on surface current and THz radiation generation have been confirmed by two-dimensional (2D) particle-in-cell (PIC) simulations and angular-dependent experiments, respectively.

12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 84(3 Pt 2): 036405, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22060511

RESUMO

Interactions of 100-fs laser pulses with solid targets at intensities of 10(18) W/cm(2) and resultant terahertz (THz) radiation are studied under different laser contrast ratio conditions. THz emission is measured in the specular reflection direction, which appears to decrease as the laser contrast ratio varies from 10(-8) to 10(-6). Correspondingly, the frequency spectra of the reflected light are observed changing from second harmonic dominant, three-halves harmonic dominant, to vanishing of both harmonics. Two-dimensional particle-in-cell simulation also suggests that this observation is correlated with the plasma density scale length change. The results demonstrate that the THz emission is closely related to the laser-plasma interaction processes. The emission is strong when resonance absorption is a key feature of the interaction, and becomes much weaker when parametric instabilities dominate.

13.
Opt Lett ; 36(14): 2608-10, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21765483

RESUMO

It is shown by simulations that terahertz (THz) radiation can be produced more efficiently by a mid-infrared laser pulse from a gas target. The THz amplitude is enhanced by 35 times as the laser wavelength increases from 1 µm to 4 µm; a 4 µm laser at 10(15) W cm(-2) produces 5 MV/cm THz radiation. The THz amplitude changes oscillatingly with increasing laser intensity for a given laser wavelength. In addition, the laser intensity threshold for the THz emission is lower for a longer laser wavelength.

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