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81.
TLRs, including TLR4, play a crucial role in inflammatory-based diseases, and TLR4 has been identified as a therapeutic target for pharmacological intervention. In previous studies, we investigated the potential of FP7, a novel synthetic glycolipid active as a TLR4 antagonist, to inhibit haematopoietic and non-haematopoietic MyD88-dependent TLR4 pro-inflammatory signalling. The main aim of this study was to investigate the action of FP7 and its derivative FP12 on MyD88-independent TLR4 signalling in THP-1 derived macrophages. Western blotting, Ab array and ELISA approaches were used to explore the effect of FP7 and FP12 on TRIF-dependent TLR4 functional activity in response to LPS and other endogenous TLR4 ligands in THP-1 macrophages. A different kinetic in the inhibition of endotoxin-driven TBK1, IRF3 and STAT1 phosphorylation was observed using different LPS chemotypes. Following activation of TLR4 by LPS, data revealed that FP7 and FP12 inhibited TBK1, IRF3 and STAT1 phosphorylation which was associated with down-regulation IFN-β and IP-10. Specific blockage of the IFN type one receptor showed that these novel molecules inhibited TRIF-dependent TLR4 signalling via IFN-β pathways. These results add novel information on the mechanism of action of monosaccharide FP derivatives. The inhibition of the TRIF-dependent pathway in human macrophages suggests potential therapeutic uses for these novel TLR4 antagonists in pharmacological interventions on inflammatory diseases.  相似文献   
82.
This report describes the length–weight relationships (LWRs) of 22 freshwater fish species from freshwater western Caribbean drainages in Venezuela. Fishes were collected in dry seasons between 2005 and 2007 with standardized electrofishing from coastal streams of Aroa, Yaracuy and Urama drainages. Results include the first LWR information for ten endemic and threatened species. Novel data on these freshwater fish faunas are important for monitoring their populations, as well as the condition of fluvial habitats to promote strategies for their conservation.  相似文献   
83.
Cleavage of eukaryotic translation initiation factor 4GI (eIF4GI) is required for shutoff of host cell translation during poliovirus (PV) infection of HeLa cells. Reports published by several groups have led to confusion whether this cleavage is mediated by viral 2A protease (2A(pro)) or a putative cellular enzyme (termed eIF4Gase) which is activated by 2A(pro) or other aspects of viral infection. Here we have further investigated eIF4Gase activities in PV-infected cells. Column purification of eIF4GI cleavage activity separated two activities which generated N-terminal cleavage products of different lengths. Both activities were detected using either native eIF4G or radiolabeled recombinant eIF4G as the substrate. Analysis of cleavage products formed by each activity on native and mutant substrates suggests that one activity cleaves eIF4G1 at or very near the 2A(pro) cleavage site and the other activity cleaves approximately 40 residues upstream of the 2A(pro) cleavage site. When PV infections in HeLa cells were supplemented with 2 mM guanidine, which indirectly limits expression of 2A(pro), two distinct C-terminal cleavage fragments of eIF4GI were detected. These C-terminal cleavage fragments of eIF4GI were purified from infected cells, and a new eIF4GI cleavage site was mapped to a unique site 43 amino acids upstream of the known 2A(pro) cleavage site. Further, eIF4GI cleavage in vivo could be blocked by addition of zVAD to PV-guanidine infections. zVAD is a broad-spectrum caspase inhibitor which had no effect on 2A(pro) cleavage activity or PV polyprotein processing. Lastly, similar types of eIF4Gase cleavage activities were also detected in uninfected cells under various conditions, including early apoptosis or during cell cycle transit. The data suggest that the same types of eIF4GI cleavage activities which are generated in PV-infected cells can also be generated in the absence of virus. Taken together, the data support a model in which multiple cellular activities process eIF4GI in PV-infected cells, in addition to 2A(pro).  相似文献   
84.
In this study, the viability of the kenaf fibre use, alone or combined with cereal straw, vine shoots and olive mill dried waste, in the elaboration of specific substrates for the cultivation of Pleurotus ostreatus (Jacq. ex Fr.) Kummer, second mushroom in importance cultivated in Spain, is described. Furthermore, three different methods of preparation of the substrate have been considered in order to obtain selectivity for the growth and later fruiting of Pleurotus sporophore. As for the production parameters, the best results have been provided by the substrates that combined kenaf with straw and with vine shoots, being unfavourable the substrates based in just kenaf or combined with olive mill dried waste. As for the treatment applied to the materials, the immersion in water alone and subsequent pasteurization and thermophilic conditioning, together with the semi-anaerobic fermentation, has been favoured in front of the immersion in water with fungicide and later pasteurization.  相似文献   
85.
We have developed a magnetic resonance imaging (MRI) method for improved detection of cancer with a new class of cancer-specific contrast agents, containing vanadyl (VO2+)-chelated organic ligands, specifically bis(acetylacetonato)oxovanadium(IV) [VO(acac)2]. Vanadyl compounds have been found to accumulate within cells, where they interact with intracellular glycolytic enzymes. Aggressive cancers are metabolically active and highly glycolytic; an MRI contrast agent that enters cells with high glycolytic activity could provide high-resolution functional images of tumor boundaries and internal structure, which cannot be achieved by conventional contrast agents. The present work demonstrates properties of VO(acac)2 that may give it excellent specificity for cancer detection. A high dose of VO(acac)2 did not cause any acute or short-term adverse reactions in murine subjects. Calorimetry and spectrofluorometric methods demonstrate that VO(acac)2 is a blood pool agent that binds to serum albumin with a dissociation constant K d ~ 2.5 ± 0.7 × 10−7 M and a binding stoichiometry n = 1.03 ± 0.04. Owing to its prolonged blood half-life and selective leakage from hyperpermeable tumor vasculature, a low dose of VO(acac)2 (0.15 mmol/kg) selectively enhanced in vivo magnetic resonance images of tumors, providing high-resolution images of their interior structure. The kinetics of uptake and washout are consistent with the hypothesis that VO(acac)2 preferentially accumulates in cancer cells. Although VO(acac)2 has a lower relaxivity than gadolinium-based MRI contrast agents, its specificity for highly glycolytic cells may lead to an innovative approach to cancer detection since it has the potential to produce MRI contrast agents that are nontoxic and highly sensitive to cancer metabolism.  相似文献   
86.

Introduction

Gene profiling may improve prognostic accuracy in patients with early breast cancer, but this technology is not widely available. We used commercial assays for qRT-PCR to assess the performance of the gene profiles included in the 70-Gene Signature, the Recurrence Score and the Two-Gene Ratio.

Methods

153 patients with early breast cancer and a minimum follow-up of 5 years were included. All tumours were positive for hormonal receptors and 38% had positive lymph nodes; 64% of patients received adjuvant chemotherapy. RNA was extracted from formalin-fixed paraffin-embedded (FFPE) specimens using a specific kit. qRT-PCR amplifications were performed with TaqMan Gene Expression Assays products. We applied the three gene-expression-based models to our patient cohort to compare the predictions derived from these gene sets.

Results

After a median follow-up of 91 months, 22% of patients relapsed. The distant metastasis-free survival (DMFS) at 5 years was calculated for each profile. For the 70-Gene Signature, DMFS was 95% -good prognosis- versus 66% -poor prognosis. In the case of the Recurrence Score, DMFS was 98%, 81% and 69% for low, intermediate and high-risk groups, respectively. Finally, for the Two-Gene Ratio, DMFS was 86% versus 70%. The 70-Gene Signature and the Recurrence Score were highly informative in identifying patients with distant metastasis, even in multivariate analysis.

Conclusion

Commercially available assays for qRT-PCR can be used to assess the prognostic utility of previously published gene expression profiles in FFPE material from patients with early breast cancer. Our results, with the use of a different platform and with different material, confirm the robustness of the 70-Gene Signature and represent an independent test for the Recurrence Score, using different primer/probe sets.  相似文献   
87.
Breeding quinoa (Chenopodium quinoa Willd.): potential and perspectives   总被引:1,自引:0,他引:1  
Quinoa (Chenopodium quinoa Willd.) originated in the Andean region of South America; this species is associated with exceptional grain nutritional quality and is highly valued for its ability to tolerate abiotic stresses. However, its introduction outside the Andes has yet to take off on a large scale. In the Andes, quinoa has until recently been marginally grown by small-scale Andean farmers, leading to minor interest in the crop from urban consumers and the industry. Quinoa breeding programs were not initiated until the 1960s in the Andes, and elsewhere from the 1970s onwards. New molecular tools available for the existing quinoa breeding programs, which are critically examined in this review, will enable us to tackle the limitations of allotetraploidy and genetic specificities. The recent progress, together with the declaration of “The International Year of the Quinoa” by the Food and Agriculture Organization of the United Nations, anticipates a bright future for this ancient species.  相似文献   
88.
Our objective was to determine the expression of the elements of the Lin28/Let-7 system, and related microRNAs (miRNAs), in early stages of human placentation and ectopic pregnancy, as a means to assess the potential role of this molecular hub in the pathogenesis of ectopic gestation. Seventeen patients suffering from tubal ectopic pregnancy (cases) and forty-three women with normal on-going gestation that desired voluntary termination of pregnancy (VTOP; controls) were recruited for the study. Embryonic tissues were subjected to RNA extraction and quantitative PCR analyses for LIN28B, Let-7a, miR-132, miR-145 and mir-323-3p were performed. Our results demonstrate that the expression of LIN28B mRNA was barely detectable in embryonic tissue from early stages of gestation and sharply increased thereafter to plateau between gestational weeks 7–9. In contrast, expression levels of Let-7, mir-132 and mir-145 were high in embryonic tissue from early gestations (≤6-weeks) and abruptly declined thereafter, especially for Let-7. Opposite trends were detected for mir-323-3p. Embryonic expression of LIN28B mRNA was higher in early stages (≤6-weeks) of ectopic pregnancy than in normal gestation. In contrast, Let-7a expression was significantly lower in early ectopic pregnancies, while miR-132 and miR-145 levels were not altered. Expression of mir-323-3p was also suppressed in ectopic embryonic tissue. We are the first to document reciprocal changes in the expression profiles of the gene encoding the RNA-binding protein, LIN28B, and the related miRNAs, Let-7a, mir-132 and mir-145, in early stages of human placentation. This finding suggests the potential involvement of LIN28B/Let-7 (de)regulated pathways in the pathophysiology of ectopic pregnancy in humans.  相似文献   
89.
Background:Hysterectomy, the most common gynecological operation, requires surgeons to counsel women about their operative risks. We aimed to develop and validate multivariable logistic regression models to predict major complications of laparoscopic or abdominal hysterectomy for benign conditions.Methods:We obtained routinely collected health administrative data from the English National Health Service (NHS) from 2011 to 2018. We defined major complications based on core outcomes for postoperative complications including ureteric, gastrointestinal and vascular injury, and wound complications. We specified 11 predictors a priori. We used internal–external cross-validation to evaluate discrimination and calibration across 7 NHS regions in the development cohort. We validated the final models using data from an additional NHS region.Results:We found that major complications occurred in 4.4% (3037/68 599) of laparoscopic and 4.9% (6201/125 971) of abdominal hysterectomies. Our models showed consistent discrimination in the development cohort (laparoscopic, C-statistic 0.61, 95% confidence interval [CI] 0.60 to 0.62; abdominal, C-statistic 0.67, 95% CI 0.64 to 0.70) and similar or better discrimination in the validation cohort (laparoscopic, C-statistic 0.67, 95% CI 0.65 to 0.69; abdominal, C-statistic 0.67, 95% CI 0.65 to 0.69). Adhesions were most predictive of complications in both models (laparoscopic, odds ratio [OR] 1.92, 95% CI 1.73 to 2.13; abdominal, OR 2.46, 95% CI 2.27 to 2.66). Other factors predictive of complications included adenomyosis in the laparoscopic model, and Asian ethnicity and diabetes in the abdominal model. Protective factors included age and diagnoses of menstrual disorders or benign adnexal mass in both models and diagnosis of fibroids in the abdominal model.Interpretation:Personalized risk estimates from these models, which showed moderate discrimination, can inform clinical decision-making for people with benign conditions who may require hysterectomy.

Hysterectomy is one of the most frequently performed surgical procedures. Canada has one of the highest rates of hysterectomy globally, with one-third of women undergoing this procedure before 60 years of age.1 Minimal access approaches are favoured by both clinicians and patients,2 and the proportion of hysterectomies being undertaken by a laparoscopic approach has increased substantially in many countries over the last 10 years.37 The evidence-based medicine paradigm for surgical approaches to hysterectomy for benign disease advocates that the chosen surgical approach should be discussed with the patient by their surgeon and decided in light of the relative benefits and risks.2 This advice is echoed by national guidelines.8,9Most clinicians undertaking hysterectomy will intuitively identify patient characteristics that have the potential to increase the complexity and complications of surgery. A 2016 systematic review of studies that reported significant associations between patient characteristics and surgical outcomes for laparoscopic hysterectomy and a 2020 population-based prospective cohort study using data from the Danish hysterectomy database have suggested that older age, race, raised body mass index (BMI), diabetes mellitus, increased uterine weight, fibroids, endometriosis and adhesions are predictors of complications in patients undergoing hysterectomy for benign indications.10,11 However, assimilating this information to individualize and anticipate the precise risk for each patient if there are multiple factors present can be challenging. A 2020 systematic review reported that surgeons in other specialties were outperformed by risk prediction models in estimating postoperative risk and outcomes; their discriminatory ability showed greater variation (C-statistic 0.51–0.75) than other risk prediction tools.12Patients should be given information about potential risks before surgery to manage expectations.13 This is especially important when surgery is considered for benign disease because nonsurgical options are often available.Our aim was to generate prediction models that can be used in conjunction with a surgeon’s intuition to enhance preoperative patient counselling and match the advances made in the technical aspects of surgery. We sought to quantify the proportion of patients who underwent hysterectomy for benign disease and will have a major complication, and to develop and validate prognostic models to individualize this risk, using a national data set.  相似文献   
90.
Zamora M  Granell M  Mampel T  Viñas O 《FEBS letters》2004,570(1-3):155-160
Cne1p, a calnexin homologue from Saccharomyces cerevisiae, has been shown to possess a conserved P-domain and lectin site as mammalian calnexin. The effect of P-domain and lectin site on the function of Cne1p was investigated in vitro using recombinant P-domain, P-domain deletion mutant of Cne1p, and lectin site mutant of Cne1ps (E181A and E398A) The binding of monoglucosylated oligosaccharide (G1M9) with Cne1p was clearly demonstrated using lectin site mutants. The P-domain deletion mutant and the letcin site mutants partially decreased the ability to suppress the aggregation of citrate synthase (CS) and chicken egg yolk immunoglobulin at levels different from Cne1p. Furthermore, the P-domain deletion mutant and the lectin site mutants decreased the ability to enhance the refolding of CS. These results suggest that the cooperation between the P-domain and the lectin site are important for the complete function of Cne1p. Thus, we conclude that P-domain in cooperation with the lectin site of Cne1p functions as a chaperone.  相似文献   
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