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71.
Characterization of Human Respiratory Syncytial Virus (HRSV) protein interactions with host cell components is crucial to devise antiviral strategies. Viral nucleoprotein, phosphoprotein and matrix protein genes were optimized for human codon usage and cloned into expression vectors. HEK-293T cells were transfected with these vectors, viral proteins were immunoprecipitated, and co-immunoprecipitated cellular proteins were identified through mass spectrometry. Cell proteins identified with higher confidence scores were probed in the immunoprecipitation using specific antibodies. The results indicate that nucleoprotein interacts with arginine methyl-transferase, methylosome protein and Hsp70. Phosphoprotein interacts with Hsp70 and tropomysin, and matrix with tropomysin and nucleophosmin. Additionally, we performed immunoprecipitation of these cellular proteins in cells infected with HRSV, followed by detection of co-immunoprecipitated viral proteins. The results indicate that these interactions also occur in the context of viral infection, and their potential contribution for a HRSV replication model is discussed.  相似文献   
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Default mode network resting state activity in posterior cingulate cortex is abnormally reduced in Alzheimer disease (AD) patients. Fluctuating cognition and electroencephalogram abnormalities are established core and supportive elements respectively for the diagnosis of dementia with Lewy bodies (DLB). Our aim was to assess whether patients with DLB with both of these features have different default mode network patterns during resting state functional magnetic resonance imaging compared with AD. Eighteen patients with DLB, 18 AD patients without fluctuating cognition, and 15 control subjects were selected after appropriate matching and followed for 2–5 years to confirm diagnosis. Independent component analysis with functional connectivity (FC) and Granger causality approaches were applied to isolate and characterize resting state networks. FC was reduced in AD and DLB patients compared with control subjects. Posterior cingulate cortex activity was lower in AD than in control subjects and DLB patients (p < 0.05). Right hemisphere FC was reduced in DLB patients in comparison with control subjects but not in patients with AD, and was correlated with severity of fluctuations (ρ = −0.69; p < 0.01). Causal flow analysis showed differences between patients with DLB and AD and control subjects.  相似文献   
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Mycobacterium smegmati s (Ms) is a nonpathogenic mycobacteria of rapid growth, which shares many characteristics with Mycobacterium tuberculosis (MTB), the major causative agent of tuberculosis. MTB has several cell wall glycolipids in common with Ms, which play an important role in the pathogenesis of tuberculosis and the induction of a protective immune response against MTB infection in some animal models. In this study, the humoral immune response and cross reactivity against MTB, of liposomes containing a mixture of cell wall glycolipids of Ms and commercial lipids was evaluated, in order to study its possible use as a component of a vaccine candidate against tuberculosis. Liposomes containing total lipids extracted from Ms, distearoyl phosphatidyl choline and cholesterol were prepared by the dehydration-rehydration technique. Balb/c mice were immunized with the liposomes obtained and the antibody response and cross reactivity against MTB were tested by ELISA. Total lipids extract from Ms showed the presence of several polar glycolipids in common with MTB, such as phosphatidylinositol mannosides. Liposomes that contained glycolipids of Ms were capable of inducing a specific IgG antibody response that allowed the recognition of surface antigens of MTB. The results of this study demonstrated the presence of immunogenic glycolipids in Ms, which could be included to enhance the protective effects of subunit vaccine formulations against tuberculosis.  相似文献   
76.
The development of a new tuberculosis (TB) vaccine has become one of the main objectives of the scientific community. Protein antigens have been widely explored as subunit TB vaccines, however lipid antigens could be equally important to be used or included in such a vaccine. The aim of this study was to demonstrate the potential of a liposome formulation composed of an extract of lipids from Mycobacterium smegmatis (Ms) as a TB vaccine candidate. We evaluated the immunogenicity of this formulation as well as the cross reactive response against antigens from Mycobacterium tuberculosis (MTb) in BALB/c mice. We determined the anti-liposome IgG response in sera from TB patients and from healthy subjects who displayed a positive (PPD+) or negative (PPD-) tuberculin skin test. A significant increase in anti-liposome IgG (p<0.05) was detected in animals immunized with Bacille Calmette-Guérin (BCG) compared with all groups, and in the group immunized with liposomes from Ms (LMs) compared to animals immunized with either LMs adjuvanted with aluminium (LMs-A) or the negative control group (phosphate buffered saline, PBS) respectively. With respect to the cross reactive response against a cocktail of cell wall antigens (CWA) from MTb, significantly higher IgG levels were observed in animals immunized with BCG and LMs compared to negative controls and either, aluminium-adjuvanted liposomes (LMs-A) or montanide (LMs-M) (p<0.05). Furthermore, the anti-liposome IgG response was significantly superior in sera from pulmonary TB patients compared to PPD+ and PPD- healthy subjects (p<0.001) suggesting the expression of these antigens in vivo during active MTb infection. The results obtained provide some evidence for the potential use of liposomes containing total lipid extracts of Ms as a TB vaccine candidate.  相似文献   
77.

The development of a new tuberculosis (TB) vaccine has become one of the main objectives of the scientific community. Protein antigens have been widely explored as subunit TB vaccines, however lipid antigens could be equally important to be used or included in such a vaccine. The aim of this study was to demonstrate the potential of a liposome formulation composed of an extract of lipids from Mycobacterium smegmatis (Ms) as a TB vaccine candidate. We evaluated the immunogenicity of this formulation as well as the cross reactive response against antigens from Mycobacterium tuberculosis (MTb) in BALB/c mice. We determined the anti-liposome IgG response in sera from TB patients and from healthy subjects who displayed a positive (PPD+) or negative (PPD-) tuberculin skin test. A significant increase in anti-liposome IgG (p<0.05) was detected in animals immunized with Bacille Calmette-Guérin (BCG) compared with all groups, and in the group immunized with liposomes from Ms (LMs) compared to animals immunized with either LMs adjuvanted with aluminium (LMs-A) or the negative control group (phosphate buffered saline, PBS) respectively. With respect to the cross reactive response against a cocktail of cell wall antigens (CWA) from MTb, significantly higher IgG levels were observed in animals immunized with BCG and LMs compared to negative controls and either, aluminium-adjuvanted liposomes (LMs-A) or montanide (LMs-M) (p<0.05). Furthermore, the anti-liposome IgG response was significantly superior in sera from pulmonary TB patients compared to PPD+ and PPD- healthy subjects (p<0.001) suggesting the expression of these antigens in vivo during active MTb infection. The results obtained provide some evidence for the potential use of liposomes containing total lipid extracts of Ms as a TB vaccine candidate.

  相似文献   
78.
Adherence to non-vitamin-K oral anticoagulants (NOACs) may be lower than to vitamin K antagonists because NOACs do not require routine monitoring. We assessed the impact of an educational program on adherence and persistence with apixaban in patients with non-valvular atrial fibrillation (NVAF). Patients with NVAF eligible for NOACs with one or more stroke risk factor (prior stroke/transient ischemic attack, age ≥ 75 years, hypertension, diabetes, or symptomatic heart failure) were randomized (1:1) to standard of care (SOC) or SOC with additional educational (information booklet, reminder tools, virtual clinic access). The primary outcome was adherence to apixaban (2.5 or 5 mg twice daily) at 24 weeks. Patients receiving the educational program were re-randomized (1:1) to continue the program for 24 further weeks or to switch to secondary SOC. Implementation adherence and persistence were reassessed at 48 weeks. In total, 1162 patients were randomized (SOC, 583; educational program, 579). Mean implementation adherence ± standard deviation (SD) at 24 weeks was 91.6% ± 17.1 for SOC and 91.9% ± 16.1 for the educational program arm; results did not differ significantly between groups at any time-point. At 48 weeks, implementation adherence was 90.4% ± 18.0, 90.1% ± 18.6, and 89.3% ± 18.1 for continued educational program, SOC, and secondary SOC, respectively; and corresponding persistence was 86.1% (95% confidence interval [CI] 81.3–89.7), 85.2% (95% CI 81.5–88.2), and 87.8% (95% CI 83.4–91.1). Serious adverse events were similar across groups. High implementation adherence and persistence with apixaban were observed in patients with NVAF receiving apixaban. The educational program did not show additional benefits. This study is registered at ClinicalTrials.gov [NCT01884350].  相似文献   
79.
BACKGROUND: Previous studies have shown that mechanical and electronic intracardiac echocardiography (ICE) improves ultrasound monitoring during transcatheter patent foramen ovale (PFO) interventional closure. OBJECTIVES: This study sought to compare the procedural data, clinical imaging quality, and effectiveness PFO closure by using two different ICE monitoring modalities. METHODS: Patients referred for PFO closure (n = 82) were randomly assigned to mechanical (group 1) or electronic (group 2) ICE monitoring of Amplatzer device implantation. The digital ICE images were evaluated offline by means of absolute visual grading analysis score (VGAS(abs)), and the residual shunting at follow-up were assessed by means of contrast echocardiographic studies, all blinded regarding the ICE closure monitoring modality. RESULTS: The two groups were comparable with respect to clinical baseline characteristics, intracardiac fossa ovalis measurements, and procedural data (fluoroscopy time, procedure time and measurement of the amount of radiation that the patients absorbed). The total VGAS(abs) ranked the mechanical clinical images in a higher order than the electronic ones (3.78 +/- 0.09 vs 3.58 +/- 0.12, P = 0.005); additionally, three patients (7.3%) of group 2 needed to cross over to mechanical ICE monitoring because a right-convex atrial septal aneurysm configured itself incompletely. No differences in rates of residual shunting were observed at 12 months follow-up between the two groups (97.5% vs 94.7%, P = 0.951). CONCLUSIONS: Electronic monitoring of PFO closure performed a less diagnostic impact than the mechanical one while maintaining comparable procedural data and clinical outcome. These results represent an important step in validating these new intracardiac ultrasound imaging modalities.  相似文献   
80.
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