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291.
292.
Pedra JH Tao J Sutterwala FS Sukumaran B Berliner N Bockenstedt LK Flavell RA Yin Z Fikrig E 《FEMS immunology and medical microbiology》2007,50(3):401-410
Human anaplasmosis is an emerging infectious disease transmitted by ticks that can be potentially fatal in the immunocompromised and the elderly. The mechanisms of defense against the causative agent, Anaplasma phagocytophilum, are not completely understood; however, interferon (IFN)-gamma plays an important role in pathogen clearance. Here, we show that IFN-gamma is regulated through an early IL-12/23p40-dependent mechanism. Interleukin (IL)-12/23p40 is regulated in macrophages and dendritic cells after activation by microbial agonists and cytokines and constitutes a subunit of IL-12 and IL-23. IL-12/23p40-deficient mice displayed an increased A. phagocytophilum burden, accelerated thrombocytopenia and increased neutrophil numbers in the spleen at day 6 postinfection. Infection of MyD88- and mitogen-activated kinase kinase 3 (MKK3)-deficient mice suggested that the early susceptibility due to IL-12/23p40 deficiency was not dependent on signaling through MyD88 or MKK3. The lack of IL-12/23p40 reduced IFN-gamma production in both CD4(+) and CD8(+) T cells although the effect was more pronounced in CD4(+) T cells. Our data suggest that the immune response against A. phagocytophilum is a multifactorial and cooperative process. The IL-12/23p40 subunit drives the CD4(+) Th1 immune response in the early phase of infection and IL-12/23p40-independent mechanisms ultimately contribute to pathogen elimination from the host. 相似文献
293.
Yoshioka Katsuji Furuya Hirokazu Sasaki Hiroyuki Saraiva Maria Joao Mascarenhas Costa Pedro P. Sakaki Yoshiyuki 《Human genetics》1989,82(1):9-13
Summary Familial amyloidotic polyneuropathy (FAP) is an autosomal dominant genetic disease characterized by systemic accumulation of amyloid fibrils. A major component of FAP anyloid has been identified as variant transthyretin (TTR, also called prealbumin). In particular, a variant with the substitution 30ValMet has been commonly found in FAP of various ethnic groups. To understand the origin and spread of the ValMet mutation, we analyzed DNA polymorphisms associated with the TTR gene in six Japanese FAP families and several Portuguese FAP patients. Three distinct haplotypes associated with the ValMet mutation were identified in Japanese FAP families, one of which was also found in Portuguese patients. On the other hand, it was found that the ValMet mutation can be explained by a C-T transition at the CpG dinucleotide sequence of a mutation hot spot. Thus, our findings indicate that the ValMet mutation has probably recurred in the human population, to generate FAP families of independent origin. 相似文献
294.
Rotllant J Ruane NM Dinis MT Canario AV Power DM 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2006,143(3):375-381
The effect of the catecholamines, adrenaline and noradrenaline, on sea bass (Dicentrarchus labrax) and sea bream (Sparus auratus) interrenal cortisol production was studied in vitro using a dynamic superfusion system technique. Increasing concentrations of catecholamines (10(-6), 10(-8) and 10(-10) M) stimulated cortisol production in a dose-dependent manner, in sea bass only. The increase in cortisol production stimulated by adrenaline (10(-6) M) and noradrenaline (10(-6) M) was inhibited by sotalol (2 x 10(-5) M), but not by prazosin suggesting that catecholamines stimulate cortisol release through the beta-receptor subtype. To evaluate catecholamine-induced signal transduction in head kidney cells, measurements of cAMP production and [H3]myo-inositol incorporation were determined in head kidney cell suspensions. Adrenaline and noradrenaline (10(-6) M) increased cAMP production, but had no effect on total inositol phosphate accumulation. These results indicate that catecholamines released from the chromaffin cells within the interrenal tissue may act as a paracrine factor to stimulate interrenal steroidogenesis in the sea bass. 相似文献
295.
Bianca Harris Ronald Klein Michael Jerosch-Herold Eric A. Hoffman Firas S. Ahmed David R. Jacobs Jr Barbara E. K. Klein Tien Y. Wong Joao A. C. Lima Mary Frances Cotch R. Graham Barr 《PloS one》2012,7(12)
Smoking causes endothelial dysfunction and systemic microvascular disease with resultant end-organ damage in the kidneys, eyes and heart. Little is known about microvascular changes in smoking-related lung disease. We tested if microvascular changes in the retina, kidneys and heart were associated with obstructive spirometry and low lung density on computed tomography. The Multi-Ethnic Study of Atherosclerosis recruited participants age 45–84 years without clinical cardiovascular disease. Measures of microvascular function included retinal arteriolar and venular caliber, urine albumin-to-creatinine ratio and, in a subset, myocardial blood flow on magnetic resonance imaging. Spirometry was measured following ATS/ERS guidelines. Low attenuation areas (LAA) were measured on lung fields of cardiac computed tomograms. Regression models adjusted for pulmonary and cardiac risk factors, medications and body size. Among 3,397 participants, retinal venular caliber was inversely associated with forced expiratory volume in one second (FEV1) (P<0.001) and FEV1/forced vital capacity (FVC) ratio (P = 0.04). Albumin-to-creatinine ratio was inversely associated with FEV1 (P = 0.002) but not FEV1/FVC. Myocardial blood flow (n = 126) was associated with lower FEV1 (P = 0.02), lower FEV1/FVC (P = 0.001) and greater percentage LAA (P = 0.04). Associations were of greater magnitude among smokers. Low lung function was associated with microvascular changes in the retina, kidneys and heart, and low lung density was associated with impaired myocardial microvascular perfusion. These cross-sectional results suggest that microvascular damage with end-organ dysfunction in all circulations may pertain to the lung, that lung dysfunction may contribute to systemic microvascular disease, or that there may be a shared predisposition. 相似文献
296.
Delphine Pessoa Caetano Souto-Maior Erida Gjini Joao S. Lopes Bruno Ce?a Cláudia T. Code?o M. Gabriela M. Gomes 《PLoS computational biology》2014,10(8)
The biological effects of interventions to control infectious diseases typically depend on the intensity of pathogen challenge. As much as the levels of natural pathogen circulation vary over time and geographical location, the development of invariant efficacy measures is of major importance, even if only indirectly inferrable. Here a method is introduced to assess host susceptibility to pathogens, and applied to a detailed dataset generated by challenging groups of insect hosts (Drosophila melanogaster) with a range of pathogen (Drosophila C Virus) doses and recording survival over time. The experiment was replicated for flies carrying the Wolbachia symbiont, which is known to reduce host susceptibility to viral infections. The entire dataset is fitted by a novel quantitative framework that significantly extends classical methods for microbial risk assessment and provides accurate distributions of symbiont-induced protection. More generally, our data-driven modeling procedure provides novel insights for study design and analyses to assess interventions. 相似文献
297.
Berto A Baker JA Mesquita JR Nascimento MS Banks M Martelli F Ostanello F Angeloni G Ruggeri FM di Bartolo I Vasickova P Diez-Valcarce M Hernandez M Rodriguez-Lazaro D van der Poel WH 《BMC research notes》2012,5(1):190
ABSTRACT: BACKGROUND: Hepatitis E virus (HEV) genotype 3 and 4 can cause liver disease in human and has its main reservoir in pigs. HEV investigations in pigs worldwide have been performed but there is still a lack of information on the infection dynamics in pig populations. FINDINGS: The HEV transmission dynamics in commercial pig farms in six different European countries was studied. The data collected show prevalence in weaners ranging from 8% to 30%. The average HEV prevalence in growers was between 20% and 44%. The fatteners prevalence ranged between 8% and 73%. Sows prevalence was similar in all countries. Boar faeces were tested for HEV only in Spain and Czech Republic, and the prevalence was 4.3% and 3.5% respectively. The collected data sets were analyzed using a recently developed model to estimate the transmission dynamics of HEV in the different countries confirming that HEV is endemic in pig farms. CONCLUSIONS: This study has been performed using similar detection methods (real time RT-PCR) for all samples and the same model (SIR model) to analyse the data. Furthermore, it describes HEV prevalence and within-herd transmission dynamics in European Countries (EU): Czech Republic, Italy, Portugal, Spain, The Netherlands and United Kingdom, confirming that HEV is circulating in pig farms from weaners to fatteners and that the reproductive number mathematical defined as R0 is in the same range for all countries studied. 相似文献
298.
Maria do Rosário Pinto Pedro Miguel Dinis Santos Parreira Marta Lima Basto Lisete dos Santos Mendes Mónico 《BMC endocrine disorders》2017,17(1):77
Background
Diabetes is one of the most common metabolic disorders, with a high prevalence of patients with poor metabolic control. Worldwide, evidence highlights the importance of developing and implementing educational interventions that can reduce this burden. The main objective of this study was to analyse the impact of a lifestyle centred intervention on glycaemic control of poorly controlled type 2 diabetic patients, followed in a Community Care Centre.Methods
A type 2 experimental design was conducted over 6 months, including 122 adults with HbA1c?≥?7.5%, randomly allocated into Experimental group (EG) or Control Group (CG). EG patients attended a specific Educational Program while CG patients frequented usual care. Personal and health characterization variables, clinical metrics and self-care activities were measured before and after the implementation of the intervention. Analysis was done by comparing gains between groups (CG vs EG) through differential calculations (post minus pre-test results) and Longitudinal analysis.Results
Statistical differences were obtained between groups for HbA1c and BMI: EG had a decrease in 11% more (effect-size r2?=?.11) than CG for HbA1c (p?<?.001) and 4% more (effect-size r2?=?.04) in BMI (p?<?.05). When controlling for socioeconomic characteristics and comorbidities that showed to be associated to each parameter in pre-test, from pre to post-test only EG participants significantly decreased HbA1c [Wilks’ ??=?.702; F(1,57)?=?24.16; p?<?.001; ηp2?=?.298; observed power?=?.998]; BMI values [Wilks’ ??=?.900; F(1,59)?=?6.57; p?=?.013; ηp2?=?.100; observed power?=?.713]; systolic Blood pressure [Wilks’ ??=?.735; F(1,61)?=?21.94; p?<?.001; ηp2?=?.265; observed power?=?.996] and diastolic Blood pressure [Wilks’ ??=?.795; F(1,59)?=?15.20; p?<?.001; ηp2?=?.205; observed power?=?.970].Conclusions
The impact of a structured multicomponent educational intervention program by itself, beyond standard educational approach alone, supported in a Longitudinal analysis that controlled variables statistically associated with clinical metrics in pre-test measures, has demonstrated its effectiveness in improving HbA1c, BMI and Blood pressure values.Trial registration
RBR-8ns8pb. (Retrospectively registered: October 30,2017).299.
Joao Tomé-Carneiro M. Carmen Crespo Emma Burgos-Ramos Cristina Tomas-Zapico Alba García-Serrano Pilar Castro-Gómez Cesar Venero Inmaculada Pereda-Pérez Shishir Baliyan Azucena Valencia Javier Fontecha Alberto Dávalos Francesco Visioli 《Molecular neurobiology》2018,55(9):7285-7296
Impaired glucose metabolism and mitochondrial decay greatly increase with age, when cognitive decline becomes rampant. No pharmacological or dietary intervention has proven effective, but proper diet and lifestyle do postpone the onset of neurodegeneration and some nutrients are being investigated. We studied insulin signaling, mitochondrial activity and biogenesis, and synaptic signaling in the hippocampus and cortex following dietary supplementation with bioactive phospholipid concentrates of krill oil (KOC), buttermilk fat globule membranes (BMFC), and a combination of both in aged rats. After 3 months of supplementation, although all groups of animals showed clear signs of peripheral insulin resistance, the combination of KOC and BMFC was able to improve peripheral insulin sensitivity. We also explored brain energy balance. Interestingly, the hippocampus of supplemented rats—mainly when supplemented with BMFC or the combination of KOC and BMFC—showed an increase in intracellular adenosine triphosphate (ATP) levels, whereas no difference was observed in the cerebral cortex. Moreover, we found a significant increase of brain-derived neurotrophic factor (BDNF) in the hippocampus of BMFC+KO animals. In summary, dietary supplementation with KOC and/or BMFC improves peripheral and central insulin resistance, suggesting that their administration could delay the onset of these phenomena. Moreover, n-3 fatty acids (FAs) ingested as phospholipids increase BDNF levels favoring an improvement in energy state within neurons and facilitating both mitochondrial and protein synthesis, which are necessary for synaptic plasticity. Thus, dietary supplementation with n-3 FAs could protect local protein synthesis and energy balance within dendrites, favoring neuronal health and delaying cognitive decline associated to age-related disrepair. 相似文献
300.
Raquel dos Santos Inês Iria Ana M. Manuel Ana P. Leandro Catarina A. C. Madeira Joao Goncalves Ana Luísa Carvalho Ana Cecília A. Roque 《Biotechnology journal》2020,15(9)
One of the trends in downstream processing comprises the use of “anything‐but‐chromatography” methods to overcome the current downfalls of standard packed‐bed chromatography. Precipitation and magnetic separation are two techniques already proven to accomplish protein purification from complex media, yet never used in synergy. With the aim to capture antibodies directly from crude extracts, a new approach combining precipitation and magnetic separation is developed and named as affinity magnetic precipitation. A precipitation screening, based on the Hofmeister series, and a commercial precipitation kit are tested with affinity magnetic particles to assess the best condition for antibody capture from human serum plasma and clarified cell supernatant. The best conditions are obtained when using PEG3350 as precipitant at 4 °C for 1 h, reaching 80% purity and 50% recovery of polyclonal antibodies from plasma, and 99% purity with 97% recovery yield of anti‐TNFα mAb from cell supernatants. These results show that the synergetic use of precipitation and magnetic separation can represent an alternative for the efficient capture of antibodies. 相似文献