105 research outputs found
as a molecule from the pole counting rule
A comprehensive study on the nature of the resonant structure is
carried out in this work. By constructing the pertinent effective Lagrangians
and considering the important final-state-interaction effects, we first give a
unified description to all the relevant experimental data available, including
the and invariant mass distributions from the process, the distribution from and
also the spectrum in the process.
After fitting the unknown parameters to the previous data, we search the pole
in the complex energy plane and find only one pole in the nearby energy region
in different Riemann sheets. Therefore we conclude that is of
molecular nature, according to the pole counting rule
method~[Nucl.~Phys.~A543, 632 (1992); Phys.~Rev.~D 35,~1633 (1987)]. We
emphasize that the conclusion based upon the pole counting method is not
trivial, since both the contact interactions and the explicit
exchanges are introduced in our analyses and they lead to the same
conclusion.Comment: 21 pages, 9 figures. To match the published version in PRD.
Additional discussion on the spectral density function is include
Physiological responses of Porphyra haitanesis to different copper and zinc concentrations
No presente estudo foram investigadas as respostas fisiolΓ³gicas da alga vermelha Porphyra haitanesis Γ s elevadas concentraçáes de cobre (acima de 50 μM) e de zinco (acima de 100 μM). Os resultados mostram que os efeitos de Cu2+ e Zn2+ sobre o crescimento, pigmentos fotossintΓ©ticos (clorofilas e carotenΓ³ides), ficobiliproteΓna e metabolismo (o espectro de emissΓ£o de fluorescΓͺncia e as atividades do fotossistema) nΓ£o seguem o mesmo padrΓ£o. A taxa de crescimento relativo foi inibida por diferentes concentraçáes de Cu2+ e, em presenΓ§a de Zn2+, aumentou ligeiramente em baixas concentraçáes (abaixo de 10 μM) e foi inibida em altas concentraçáes. Por outro lado, os teores de ficoeritrina apresentaram leve aumento em concentraçáes relativamente baixas de Cu2+ e Zn2+ (atΓ© 1 μM Cu2+ e atΓ© 20 μM Zn2+, respectivamente) e foram inibidas por altas concentraçáes. AlΓ©m disso, tanto a fotossΓntese quanto a respiração mostraram aumento nas trocas de oxigΓͺnio em resposta Γ s concentraçáes relativamente baixas de Cu2+ (atΓ© 1 μM) e de Zn2+ (atΓ© 10 μM), alΓ©m da redução em concentraçáes relativamente altas desses metais. Adicionalmente, as atividades fotoredutoras e as emissΓ΅es de fluorescΓͺncia do fotossistema II (PSII) foram incrementadas em baixas concentraçáes de Cu2+ (atΓ© 0,1 μM) e de Zn2+ (atΓ© 10 μM) e inibidas por altas concentraçáes. Desta forma, a intensidade da fluorescΓͺncia da clorofila-a e dos centros de reação ativa PSII seguiram um padrΓ£o semelhante em resposta Γ s elevadas concentraçáes de Cu2+ e Zn2+. Esses resultados sugerem que baixas concentraçáes de Cu2+ e Zn2+ afetam o metabolismo de P. haitanesis, que se torna inibido por altas concentraçáes desses metais.In the present study, several physiological responses of the red marine alga Porphyra haitanesis to elevated concentrations of copper (up to 50 μM) and zinc (up to 100 μM) were investigated. Our results showed that the effects of Cu2+ and Zn2+ on growth, photosynthetic pigments (chlorophylls and carotenoids), phycobiliprotein and metabolism (the fluorescence emission spectra and the activities of photosystemII) did not follow the same pattern. The relative growth rate was inhibited by different concentrations of Cu2+, and was slightly increased at lower concentrations (up to 10 μM) and inhibited at higher Zn2+concentrations. On the other hand, the phycoerythrin contents were slightly increased at relatively low concentrations (up to 1 μM Cu2+ or 20 μM Zn2+) and inhibited by high Cu2+ and Zn2+ concentrations. Moreover, photosynthesis and respiration showed an increase in the amount of oxygen exchange in response to relatively low Cu2+ (up to 1 μM) and Zn2+ concentrations (up to 10 μM), and a reduction to relatively high Cu2+ and Zn2+ concentrations. Oxygen evolution was more sensitive than oxygen uptake to Cu2+ and Zn2+. In addition, the photoreductive activities and fluorescence emission of photosystem II (PS II) were enhanced by lower concentrations of Cu2+ (up to 0.1 μM) and Zn2+ (up to 10 μM) and inhibited by higher concentrations. Furthermore, the intensity of chlorophyll a fluorescence and the active PSII reaction centers followed a similar pattern in response to elevated concentrations of Cu2+ and Zn2+. These results suggest that lower concentrations of Cu2+ and Zn2+ affected the metabolism of P. haitanesis, which was inhibited by higher concentrations of these metals
Physalis pubescens L. branch and leaf extracts inhibit lymphoma proliferation by inducing apoptosis and cell cycle arrest
Physalis pubescens L. is an annual or perennial plant in the family Solanaceae It is used in traditional medicine for treating sore throats, coughs, urinary discomfort, and astringent pain, and externally for pemphigus and eczema in northern China. The proliferation inhibitory activity and mechanisms of the ethyl acetate extract (PHY-EA) from the leaves of Physalis pubescens were investigated. High performance liquid chromatography was used to identify the chemical composition of PHY-EA; sulforhodamine B was used to detect the proliferation inhibitory effect of PHY-EA on MCF-7, CA-46, Hela, HepG2, B16, and other tumor cells; flow cytometry was used to detect the effect of PHY-EA on the lymphoma cell cycle and apoptosis; Western blot was used to detect the expression of the cycle- and apoptosis-related proteins. The expression of Ki-67 and cleaved caspase 3 was detected by immunohistochemistry. The results showed that PHY-EA contained physalin B, physalin O, and physalin L. PHY-EA blocked the cell cycle of G2/MβG0/G1 in lymphoma cells and induced apoptosis in tumor cells. Mouse transplantation tumor experiments showed that PHY-EA had a significant inhibitory effect on mouse transplantation tumors, and the tumor volume and weight were significantly reduced. In conclusion, PHY-EA has a good antiproliferative effect on Burkkit lymphoma, indicating its potential medicinal value
Acute Response of Peripheral Blood Cell to Autologous Hematopoietic Stem Cell Transplantation in Type 1 Diabetic Patient
Autologous nonmyeloablative hematopoietic stem cell transplantation (AHST) was the first therapeutic approach that can improve Ξ² cell function in type 1 diabetic (T1D) patients. This study was designed to investigate the potential mechanisms involved.We applied AHST to nine T1D patients diagnosed within six months and analyzed the acute responses in peripheral blood for lymphocyte subpopulation as well as for genomic expression profiling at the six-month follow-up.We found six patients obtained insulin free (IF group) and three remained insulin dependent (ID group); C-peptide production was significantly higher in IF group compared to ID group. The acute responses in lymphocytes at six-month follow-up include declined CD3(+)CD4(+), CD3(+)CD8(+) T cell population and recovered B cell, NK cell population in both groups but with no significant differences between the two groups; most immune-related genes and pathways were up-regulated in peripheral blood mononuclear cell (PBMC) of both groups while none of transcription factors for immune regulatory component were significantly changed; the IF group demonstrated more AHST-modified genetic events than the ID group and distinct pattern of top pathways, co-expression network as well as 'hub' genes (eg, TCF7 and GZMA) were associated with each group.AHST could improve the islet function in newly diagnosed T1D patients and elimination of the islet specific autoreactive T cells might be one of the mechanisms involved; T1D patients responded differently to AHST possibly due to the distinct transcriptional events occurring in PBMC.ClinicalTrials.gov NCT00807651
Exploring the Caffeine-Induced Teratogenicity on Neurodevelopment Using Early Chick Embryo
Caffeine consumption is worldwide. It has been part of our diet for many centuries; indwelled in our foods, drinks, and medicines. It is often perceived as a βlegal drugβ, and though it is known to have detrimental effects on our health, more specifically, disrupt the normal fetal development following excessive maternal intake, much ambiguity still surrounds the precise mechanisms and consequences of caffeine-induced toxicity. Here, we employed early chick embryos as a developmental model to assess the effects of caffeine on the development of the fetal nervous system. We found that administration of caffeine led to defective neural tube closures and expression of several abnormal morphological phenotypes, which included thickening of the cephalic mesenchymal tissues and scattering of somites. Immunocytochemistry of caffeine-treated embryos using neural crest cell markers also demonstrated uncharacteristic features; HNK1 labeled migratory crest cells exhibited an incontinuous dorsal-ventral migration trajectory, though Pax7 positive cells of the caffeine-treated groups were comparatively similar to the control. Furthermore, the number of neurons expressing neurofilament and the degree of neuronal branching were both significantly reduced following caffeine administration. The extent of these effects was dose-dependent. In conclusion, caffeine exposure can result in malformations of the neural tube and induce other teratogenic effects on neurodevelopment, although the exact mechanism of these effects requires further investigation
HDAC Inhibitors Act with 5-aza-2β²-Deoxycytidine to Inhibit Cell Proliferation by Suppressing Removal of Incorporated Abases in Lung Cancer Cells
5-aza-2β²-deoxycytidine (5-aza-CdR) is used extensively as a demethylating agent and acts in concert with histone deacetylase inhibitors (HDACI) to induce apoptosis or inhibition of cell proliferation in human cancer cells. Whether the action of 5-aza-CdR in this synergistic effect results from demethylation by this agent is not yet clear. In this study we found that inhibition of cell proliferation was not observed when cells with knockdown of DNA methyltransferase 1 (DNMT1), or double knock down of DNMT1-DNMT3A or DNMT1-DNMT3B were treated with HDACI, implying that the demethylating function of 5-aza-CdR may be not involved in this synergistic effect. Further study showed that there was a causal relationship between 5-aza-CdR induced DNA damage and the amount of [3H]-5-aza-CdR incorporated in DNA. However, incorporated [3H]-5-aza-CdR gradually decreased when cells were incubated in [3H]-5-aza-CdR free medium, indicating that 5-aza-CdR, which is an abnormal base, may be excluded by the cell repair system. It was of interest that HDACI significantly postponed the removal of the incorporated [3H]-5-aza-CdR from DNA. Moreover, HDAC inhibitor showed selective synergy with nucleoside analog-induced DNA damage to inhibit cell proliferation, but showed no such effect with other DNA damage stresses such as Ξ³-ray and UV, etoposide or cisplatin. This study demonstrates that HDACI synergistically inhibits cell proliferation with nucleoside analogs by suppressing removal of incorporated harmful nucleotide analogs from DNA
- β¦