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101.
Xinqiong Huang Yujie Qian Hainan Wu Xiaoxue Xie Qin Zhou Ying Wang Weilu Kuang Lin Shen Kai Li Juan Su Liangfang Shen Xiang Chen 《The journal of histochemistry and cytochemistry》2015,63(2):88-98
Radiotherapy is the first-line treatment for all stages of cervical cancer, whether it is used for radical or palliative therapy. However, radioresistance of cervical cancer remains a major therapeutic problem. Consequently, we explored if E-cadherin (a marker of epithelial-mesenchymal transition) and osteopontin could predict radioresistance in patients with locally advanced cervical squamous cell carcinoma (LACSCC). Patients were retrospectively reviewed and 111 patients divided into two groups (radiation-resistant and radiation-sensitive groups) according to progression-free survival (PFS). In pretreated paraffin-embedded tissues, we evaluated E-cadherin and osteopontin expression using immunohistochemical staining. The percentage of patients with high osteopontin but low E-cadherin expression in the radiation-resistant group was significantly higher than those in the radiation-sensitive group (p<0.001). These patients also had a lower 5-year PFS rate (p<0.001). Our research suggests that high osteopontin but low E-cadherin expression can be considered as a negative, independent prognostic factor in patients with LACSCC ([Hazard ratios (95% CI) 6.766 (2.940, 15.572)], p<0.001). 相似文献
102.
Lin Wei Jiuxiang Gao Shumin Zhang Sijin Wu Zeping Xie Guiying Ling Yi-Qun Kuang Yongliang Yang Haining Yu Yipeng Wang 《The Journal of biological chemistry》2015,290(27):16633-16652
Cathelicidins are a family of gene-encoded peptide effectors of innate immunity found exclusively in vertebrates. They play pivotal roles in host immune defense against microbial invasions. Dozens of cathelicidins have been identified from several vertebrate species. However, no cathelicidin from marine reptiles has been characterized previously. Here we report the identification and characterization of a novel cathelicidin (Hc-CATH) from the sea snake Hydrophis cyanocinctus. Hc-CATH is composed of 30 amino acids, and the sequence is KFFKRLLKSVRRAVKKFRKKPRLIGLSTLL. Circular dichroism spectroscopy and structure modeling analysis indicated that Hc-CATH mainly assumes an amphipathic α-helical conformation in bacterial membrane-mimetic solutions. It possesses potent broad-spectrum and rapid antimicrobial activity. Meanwhile, it is highly stable and shows low cytotoxicity toward mammalian cells. The microbial killing activity of Hc-CATH is executed through the disruption of cell membrane and lysis of bacterial cells. In addition, Hc-CATH exhibited potent anti-inflammatory activity by inhibiting the LPS-induced production of nitric oxide (NO) and pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6. Hc-CATH directly binds with LPS to neutralize its toxicity, and it also binds to Toll-like receptor 4 (TLR4/MD2 complex), which therefore inhibits the binding of LPS to TLR4/MD2 complex and the subsequent activation of LPS-induced inflammatory response pathways. Taken together, our study demonstrates that Hc-CATH, the first cathelicidin from sea snake discovered to have both antimicrobial and anti-inflammatory activity, is a potent candidate for the development of peptide antibiotics. 相似文献
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106.
Identification of Campylobacter jejuni and determination of point mutations associated with macrolide resistance using a multiplex TaqMan MGB real‐time PCR 下载免费PDF全文
107.
Kuang H Zhao S Chen W Ma W Yong Q Xu L Wang L Xu C 《Biosensors & bioelectronics》2011,26(5):2495-2499
A novel, rapid DNA detection method based on fluorescence quenching of quantum dots (QDs) by gold nanoparticles (GNPs) through polymerase chain reaction (PCR) was developed. In proof-of-concept experiments, the length of the amplicon DNA ranging from 152 to 1003 base pairs (bp) could be determined based on quenched fluorescence intensity with 136 bp as the lower limit of effective range. And the real sample detections were also achieved successfully by this developed method. Therefore, this DNA detection method has the potential to be the powerful gene diagnostic tool. 相似文献
108.
An all-electron scalar relativistic calculation was performed on Au
n
H2O (n = 1–13) clusters using density functional theory (DFT) with the generalized gradient approximation at PW91 level. The calculation
results reveal that, after adsorption, the small gold cluster would like to bond with oxygen and the H2O molecule prefers to occupy the single fold coordination site. Reflecting the strong scalar relativistic effect, Au
n
geometries are distorted slightly but still maintain a planar structure. The Au–Au bond is strengthened and the H–O bond
is weakened, as manifested by the shortening of the Au–Au bond-length and the lengthening of the H–O bond-length. The H–O–H
bond angle becomes slightly larger. The enhancement of reactivity of the H2O molecule is obvious. The Au–O bond-lengths, adsorption energies, VIPs, HLGs, HOMO (LUMO) energy levels, charge transfers
and the highest vibrational frequencies of the Au–O mode for Au
n
H2O clusters exhibit an obvious odd-even oscillation. The most favorable adsorption between small gold clusters and the H2O molecule takes place when the H2O molecule is adsorbed onto an even-numbered Au
n
cluster and becomes an Au
n
H2O cluster with an even number of valence electrons. The odd–even alteration of magnetic moments is observed in Au
n
H2O clusters and may serve as material with a tunable code capacity of “0” and “1” by adsorbing a H2O molecule onto an odd or even-numbered small gold cluster. 相似文献
109.
During cotranslational protein targeting by the Signal Recognition Particle (SRP), the correct cargo accelerates stable complex assembly between the SRP and SRP receptor (FtsY) by several orders of magnitude, thus enabling rapid and faithful cargo delivery to the target membrane. The molecular mechanism underlying this cargo-induced rate acceleration has been unclear. Here we show that the SRP RNA allows assembly of the SRP-FtsY complex to be specifically stimulated by a correct cargo, and, reciprocally, a correct cargo enables the SRP RNA to optimize its electrostatic interactions with FtsY. These results combined with recent structural work led us to suggest a "conformational selection" model that explains the synergistic action of the SRP RNA with the cargo in accelerating complex assembly. In addition to its previously proposed role in preventing the premature dissociation of SRP and FtsY, we found that the SRP RNA also plays an active role in ensuring the formation of productive assembly intermediates, thus guiding the SRP and FtsY through the most efficient pathway of assembly. 相似文献
110.
Malaria continues to be one of the most devastating global health problems due to the high morbidity and mortality it causes in endemic regions. The search for new antimalarial targets is of high priority because of the increasing prevalence of drug resistance in malaria parasites. Malarial proteases constitute a class of promising therapeutic targets as they play important roles in the parasite life cycle and it is possible to design and screen for specific protease inhibitors. In this mini-review, we provide a phylogenomic overview of malarial proteases. An evolutionary perspective on the origin and divergence of these proteases will provide insights into the adaptive mechanisms of parasite growth, development, infection, and pathogenesis.B. 相似文献