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121.
Our previous studies showed that recombinant high-density lipoprotein (rHDL) rHDL74 exhibited higher anti-inflammatory capabilities compared to wild-type rHDL (rHDLwt), while rHDL228 showed hyper-proinflammation. In this paper, we further investigated the potential mechanisms involved in their different inflammatory functions using two models: endotoxemic mice and the RAW264.7 inflammation model. Our results showed that 24 h after the injection of lipopolysaccharide (LPS), mice treated with rHDL74 had a significant decrease in plasma CRP (P<0.01 vs. rHDLwt; P<0.01 vs. LPS), MCP-1 (P<0.05 vs. rHDLwt; P<0.01 vs. LPS) and CD14 (P<0.01 vs. LPS) compared with the mice treated with rHDLwt or the controls that received LPS only. Similar to our previous study, rHDL228 increased the plasma level of CRP (P<0.05 vs. LPS) and MCP-1 (P<0.01 vs. LPS). Our immunohistochemistry and western blot analysis showed that rHDL74 inhibited the activation of NF-κB in endotoxemic mice and JNK and p38 in the RAW264.7 inflammation model, while rHDL228 exacerbated the activation of NF-κB and ERK. In summary, our data suggest that rHDL74 exhibits higher anti-inflammatory activity by decreasing inflammatory factors and inhibiting the activation of NF-κB, JNK and p38, while rHDL228 appears to be hyper-proinflammation by increasing these inflammatory factors and aggravating the activation of NF-κB and ERK.  相似文献   
122.
Cassettes harboring luciferase reporter driven by Bombyx mori cytoplasmic actin gene promoter (A3) (671 bp) and B. mori nuclear polyhedrosis virus immediate-early promoter (IE-1) (580 bp) were transferred to the bacmid AcΔEGT to generate the recombinant Autographa californica nuclear polyhedrosis viruses, AcNPVA3Luc and AcNPVIELuc, respectively. Recombinant baculoviruses were injected into the hemocoele of newly ecdysed 5th instar larvae. The activities of the A3 and IE-1 promoters in various tissues were measured by luciferase activity assay and normalized by the copy number of recombinant virus. Results showed that the activity of the A3 promoter was approximately 10-fold higher than the IE-1 promoter. The promoter activities of A3 and IE-1 were highest in the silk gland, followed by fat body, middle gut, Malpighian tubule, and hemocyte. In silk gland, activity of the two promoters was highest in posterior silk gland, followed by middle and anterior silk glands. The difference in promoter activities reflects the growth speed of tissue in silkworm larvae. The activity of the A3 promoter remained unchanged and was not inhibited significantly by viral factors at least 3–4 d post injection of rAcNPV.  相似文献   
123.
Because of the recent observation of the toxic side effects of Gd(III) based MRI contrast agents in patients with impaired renal function, there is strong interest on developing alternative contrast agents for MRI. In this study, macrocyclic Mn(II) chelates were conjugated to nanoglobular carriers, lysine dendrimers with a silsesquioxane core, to synthesize non-Gd(III) based MRI contrast agents. A generation 3 nanoglobular conjugate of Mn(II)-1,4,7-triaazacyclononane-1,4,7-triacetate-GA amide (G3-NOTA-Mn) was also synthesized and evaluated. The per ion T(1) and T(2) relaxivities of G2, G3, G4 nanoglobular Mn(II)-DOTA monoamide conjugates decreased with increasing generation of the carriers. The T(1) relaxivities of G2, G3, and G4 nanoglobular Mn(II)-DOTA conjugates were 3.3, 2.8, and 2.4 mM(-1) s(-1) per Mn(II) chelate at 3 T, respectively. The T(1) relaxivity of G3-NOTA-Mn was 3.80 mM(-1) s(-1) per Mn(II) chelate at 3 T. The nanoglobular macrocyclic Mn(II) chelate conjugates showed good in vivo stability and were readily excreted via renal filtration. The conjugates resulted in much less nonspecific liver enhancement than MnCl(2) and were effective for contrast-enhanced tumor imaging in nude mice bearing MDA-MB-231 breast tumor xenografts at a dose of 0.03 mmol Mn/kg. The nanoglobular macrocyclic Mn(II) chelate conjugates are promising nongadolinium based MRI contrast agents.  相似文献   
124.
Both the Taihang Mountain area in north-central China and Chaoshan area in the southeastern littoral of China are areas with high risk of esophageal cancer (EC). Our previous study confirmed that populations from the two areas might share similar matrilineal backgrounds and found that mitochondrial DNA (mtDNA) haplogroup D, especially subhaplogroups D4a and D5a, might be genetic background markers of EC in Chaoshan area. Here, to further determine whether D4a, D5a, and D might be susceptibility markers for EC in the two high-risk areas, we performed a case–control study with larger samples and analyzed the distributions of these three haplogroups in subjects (controls [n = 898] and patients [n = 768]) from the two areas. D4a haplogroup was significantly associated with increased risk of EC in Taihang Mountain subjects, especially women. D5 haplogroup was associated with EC at the general population level in the Taihang Mountain area and in subjects ≤ 60 years, especially women ≤ 60 years, in the Chaoshan area. D haplogroup was associated with EC only in subjects ≤ 60 years, especially men ≤ 60 years, in the Chaoshan area. D4a and D5 showing positive association with EC in the Taihang Mountain area became the predominant subhaplogroups of D in Chaoshan controls. In conclusion, D, D4a, and D5 haplogroups might be susceptibility markers for EC in the two high-risk areas in China, particularly D4a and D5 for the Taihang Mountain area and D and D5 for the Chaoshan area.  相似文献   
125.

Background

Health-related Quality of Life (HrQoL) is a multidimensional measure, which has gained clinical and social relevance. Implementation of a patient-centred approach to both clinical research and care settings, has increased the recognition of patient and/or observer reported outcome measures (PROMs or ObsROMs) as informative and reliable tools for HrQoL assessment. Inherited Metabolic Diseases (IMDs) are a group of heterogeneous conditions with phenotypes ranging from mild to severe and mostly lacking effective therapies. Consequently, HrQoL evaluation is particularly relevant.

Objectives

We aimed to: (1) identify patient and/or caregiver-reported HrQoL instruments used among IMDs; (2) identify the main results of the application of each HrQoL tool and (3) evaluate the main limitations of HrQoL instruments and study design/methodology in IMDs.

Methods

A scoping review was conducted using methods outlined by Arksey and O’Malley. Additionally, we critically analysed each article to identify the HrQoL study drawbacks.

Results

Of the 1954 studies identified, 131 addressed HrQoL of IMDs patients using PROMs and/or ObsROMs, both in observational or interventional studies. In total, we identified 32 HrQoL instruments destined to self- or proxy-completion; only 2% were disease-specific. Multiple tools (both generic and disease-specific) proved to be responsive to changes in HrQoL; the SF-36 and PedsQL questionnaires were the most frequently used in the adult and pediatric populations, respectively. Furthermore, proxy data often demonstrated to be a reliable approach complementing self-reported HrQoL scores. Nevertheless, numerous limitations were identified especially due to the rarity of these conditions.

Conclusions

HrQoL is still not frequently assessed in IMDs. However, our results show successful examples of the use of patient-reported HrQoL instruments in this field. The importance of HrQoL measurement for clinical research and therapy development, incites to further research in HrQoL PROMs’ and ObsROMs’ creation and validation in IMDs.
  相似文献   
126.
On semiparametric transformation cure models   总被引:4,自引:0,他引:4  
Lu  Wenbin; Ying  Zhiliang 《Biometrika》2004,91(2):331-343
  相似文献   
127.
Promoter methylation of the O6-methylguanine-DNA-methyltransferase (MGMT) gene has been considered a prognostic marker and has become more important in the treatment of glioblastoma. However, reports on the correlation between MGMT and clinical outcomes in Chinese glioblastoma patients are very scarce. In this study, quantitative methylation data were obtained by the pyrosequencing of tumor tissues from 128 GBM patients. The median overall survival (OS) was 13.1 months, with a 1-year survival of 45.3%. The pyrosequencing data were reproducible based on archived samples yielding data for all glioblastomas. MGMT promoter methylation was detected in 75/128 cases (58.6%), whereas 53/128 (41.4%) cases were unmethylated. Further survival analysis also revealed that methylation was an independent prognostic factor associated with prolonged OS but not with progression-free survival (PFS) (p = 0.029 and p = 0.112, respectively); the hazard radios were 0.63 (95% CI: 0.42–0.96) and 0.72 (95% CI: 0.48–1.09), respectively. These data indicated that MGMT methylation has prognostic significance in patients with newly diagnosed high-grade glioblastoma undergoing alkylating agent-based chemotherapy after surgical resection.  相似文献   
128.
In this study, hydrogels for DNA-controlled release was prepared with konjac glucomannan (KGM), a water-soluble non-ionic polysaccharide, by means of deacetylated reaction and physically cross-linking method under mild conditions. The properties of the KGM hydrogels were analyzed by FTIR spectra and scanning electron microscopy (SEM). The integrality of the released DNA was investigated by circular dichroism (CD). The DNA release kinetics was performed using the DNA-loaded KGM gels in buffer solutions of pH 7.4 at 37+/-0.5 degrees C. Peppas model and Higuchi model were used to analysis the DNA release mechanism; the data indicated that the DNA release can be controlled by changing the preparation conditions and the structure parameters of the gels. This study suggested that the KGM hydrogels have a potential use for advanced controlled release.  相似文献   
129.
5-[76Br]Bromo-3-[[2(S)-azetidinyl]methoxy]pyridine ([76Br]BAP), a novel nicotinic acetylcholine receptor ligand, was synthesized using [76Br]bromide in an oxidative bromodestannylation of the corresponding trimethylstannyl compound. The radiochemical yield was 25%, and the specific radioactivity was on the order of 1 Ci/micromol. The binding properties of [76Br]BAP were characterized in vitro and in vivo in rat brain, and positron emission tomography (PET) experiments were performed in two rhesus monkeys. In association experiments on membranes of the cortex and thalamus, >90% of maximal specific [76Br]BAP binding was obtained after 60 min. The dissociation half-life of [76Br]BAP was 51 +/- 6 min in cortical membranes and 56 +/- 3 min in thalamic membranes. Saturation experiments with [76Br]BAP revealed one population of binding sites with dissociation constant (K(D)) values of 36 +/- 9 and 30 +/- 9 pM in membranes of cortex and thalamus, respectively. The maximal binding site density (Bmax) values were 90 +/- 17 and 207 +/- 33 fmol/mg in membranes of cortex and thalamus, respectively. Scatchard plots were nonlinear, and the Hill coefficients were <1, suggesting the presence of a lower-affinity binding site. In vitro autoradiography studies showed that binding of [76Br]BAP was high in the thalamus and presubiculum, moderate in the cortex and striatum, and low in the cerebellum and hippocampus. A similar pattern of [76Br]BAP accumulation was observed by ex vivo autoradiography. In vivo, binding of [76Br]BAP in whole rat brain was blocked by preinjection of (S)(-)-nicotine (0.3 mg/kg) by 27, 52, 68, and 91% at survival times of 10, 25, 40, 120, and 300 min, respectively. In a preliminary PET study in rhesus monkeys, the highest [76Br]BAP uptake was found in the thalamus, and radioactivity was displaceable by approximately 60% with cytisine and by 50% with (S)(-)-nicotine. The data of this study indicate that [76Br]BAP is a promising radioligand for the characterization of nicotinic acetylcholine receptors in vivo.  相似文献   
130.
A novel strategy based on carboxy group derivatization is presented for specific characterization of phosphopeptides. By tagging the carboxy group with 1‐(2‐pyrimidyl) piperazine (PP), the ion charge states of phosphopeptides can be largely enhanced, showing great advantages for sequencing phosphorylated peptides with electron‐transfer dissociation MS. Besides, after PP‐derivatization, most non‐specific bindings can be avoided by eliminating the interaction between the carboxy group and TiO2, greatly improving the specificity of TiO2‐based phosphopeptide enrichment strategy. Moreover, being tagged with a hydrophobic group, the retention time of phosphopeptides in RPLC can be prolonged, overcoming the difficulty of separating phosphopeptides in RPLC‐based approach. Together with several other advantages, such as ease of handling, rapid reaction time, broad applicability and good reproducibility, this PP‐derivatization method is promising for high‐throughput phosphoproteome research.  相似文献   
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