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131.
Alexsandra R.m. Favacho Isabelle Roger Amanda K. Akemi Adonai A. Pessoa JR. Andrea G. Varon Raphael Gomes Daniela T. Godoy Sandro Pereira Elba R.s. Lemos 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(4):363-365
Bartonella henselae is associated with a wide spectrum of clinical
manifestations, including cat scratch disease, endocarditis and meningoencephalitis,
in immunocompetent and immunocompromised patients. We report the first molecularly
confirmed case of B. henselae infection in an AIDS patient in state
of Rio de Janeiro, Brazil. Although DNA sequence of B. henselae has
been detected by polymerase chain reaction in a lymph node biopsy, acute and
convalescent sera were nonreactive. 相似文献
132.
133.
Patel PR Ramakrishnan SK Kaw MK Raphael CK Ghosh S Marino JS Heinrich G Lee SJ Bourey RE Hill JW Jung DY Morgan DA Kim JK Rahmouni K Rahmouni SK Najjar SM 《Diabetologia》2012,55(3):763-772
Aims/hypothesis
The carcino-embryonic antigen-related cell adhesion molecule (CEACAM)2 is produced in many feeding control centres in the brain, but not in peripheral insulin-targeted tissues. Global Ceacam2 null mutation causes insulin resistance and obesity resulting from hyperphagia and hypometabolism in female Ceacam2 homozygous null mutant mice (Cc2 [also known as Ceacam2]?/?) mice. Because male mice are not obese, the current study examined their metabolic phenotype.Methods
The phenotype of male Cc2 ?/? mice was characterised by body fat composition, indirect calorimetry, hyperinsulinaemic?Ceuglycaemic clamp analysis and direct recording of sympathetic nerve activity.Results
Despite hyperphagia, total fat mass was reduced, owing to the hypermetabolic state in male Cc2 ?/? mice. In contrast to females, male mice also exhibited insulin sensitivity with elevated ??-oxidation in skeletal muscle, which is likely to offset the effects of increased food intake. Males and females had increased brown adipogenesis. However, only males had increased activation of sympathetic tone regulation of adipose tissue and increased spontaneous activity. The mechanisms underlying sexual dimorphism in energy balance with the loss of Ceacam2 remain unknown.Conclusions/interpretation
These studies identified a novel role for CEACAM2 in the regulation of metabolic rate and insulin sensitivity via effects on brown adipogenesis, sympathetic nervous outflow to brown adipose tissue, spontaneous activity and energy expenditure in skeletal muscle. 相似文献134.
Jacob CO Eisenstein M Dinauer MC Ming W Liu Q John S Quismorio FP Reiff A Myones BL Kaufman KM McCurdy D Harley JB Silverman E Kimberly RP Vyse TJ Gaffney PM Moser KL Klein-Gitelman M Wagner-Weiner L Langefeld CD Armstrong DL Zidovetzki R 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(2):E59-E67
Systemic lupus erythematosus (SLE), the prototypic systemic autoimmune disease, is a debilitating multisystem autoimmune disorder characterized by chronic inflammation and extensive immune dysregulation in multiple organ systems, resulting in significant morbidity and mortality. Here, we present a multidisciplinary approach resulting in the identification of neutrophil cytosolic factor 2 (NCF2) as an important risk factor for SLE and the detailed characterization of its causal variant. We show that NCF2 is strongly associated with increased SLE risk in two independent populations: childhood-onset SLE and adult-onset SLE. The association between NCF2 and SLE can be attributed to a single nonsynonymous coding mutation in exon 12, the effect of which is the substitution of histidine-389 with glutamine (H389Q) in the PB1 domain of the NCF2 protein, with glutamine being the risk allele. Computational modeling suggests that the NCF2 H389Q mutation reduces the binding efficiency of NCF2 with the guanine nucleotide exchange factor Vav1. The model predicts that NCF2/H389 residue interacts with Vav1 residues E509, N510, E556, and G559 in the ZF domain of Vav1. Furthermore, replacing H389 with Q results in 1.5 kcal/mol weaker binding. To examine the effect of the NCF2 H389Q mutation on NADPH oxidase function, site-specific mutations at the 389 position in NCF2 were tested. Results show that an H389Q mutation causes a twofold decrease in reactive oxygen species production induced by the activation of the Vav-dependent Fcγ receptor-elicited NADPH oxidase activity. Our study completes the chain of evidence from genetic association to specific molecular function. 相似文献
135.
Gefen G Anbar M Morag E Lamed R Bayer EA 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(26):10298-10303
The conversion of recalcitrant plant-derived cellulosic biomass into biofuels is dependent on highly efficient cellulase systems that produce near-quantitative levels of soluble saccharides. Similar to other fungal and bacterial cellulase systems, the multienzyme cellulosome system of the anaerobic, cellulolytic bacterium Clostridium thermocellum is strongly inhibited by the major end product cellobiose. Cellobiose-induced inhibition can be relieved via its cleavage to noninhibitory glucose by the addition of exogenous noncellulosomal enzyme β-glucosidase; however, because the cellulosome is adsorbed to the insoluble substrate only a fraction of β-glucosidase would be available to the cellulosome. Towards this end, we designed a chimeric cohesin-fused β-glucosidase (BglA-CohII) that binds directly to the cellulosome through an unoccupied dockerin module of its major scaffoldin subunit. The β-glucosidase activity is thus focused at the immediate site of cellobiose production by the cellulosomal enzymes. BglA-CohII was shown to retain cellobiase activity and was readily incorporated into the native cellulosome complex. Surprisingly, it was found that the native C. thermocellum cellulosome exists as a homooligomer and the high-affinity interaction of BglA-CohII with the scaffoldin moiety appears to dissociate the oligomeric state of the cellulosome. Complexation of the cellulosome and BglA-CohII resulted in higher overall degradation of microcrystalline cellulose and pretreated switchgrass compared to the native cellulosome alone or in combination with wild-type BglA in solution. These results demonstrate the effect of enzyme targeting and its potential for enhanced degradation of cellulosic biomass. 相似文献
136.
A qualitative study was undertaken to investigate the perceptions of General Practitioners regarding the management of older people with heart failure, particularly at the end of life. Semi-structured interviews were conducted with 30 General Practitioners in Auckland, New Zealand during 2008. Participants identified that the needs of older patients with heart failure could not be addressed in isolation from the wider issues which affect older people. This complexity influenced all components of patient need including the typical course of the disease, the provision of prognostic and end of life information, and how palliative care was provided, including referral to specialist services. Some participants also believed that older people??s palliative care management should be approached differently to that of younger people stating, for example, that they were concerned about the amount of information older people could take in. A model which takes into consideration the experiences of the older person and fits them into, not a ??dying model?? but a ??life model??, one that supports the natural transition to end of life is needed. A ??life planning model?? used early in the management of patients would be a useful way forward and one which would allow the integration of the different paradigms of cardiology, gerontology, palliative care and nursing. 相似文献
137.
Meune C Twerenbold R Drexler B Balmelli C Wolf C Haaf P Reichlin T Irfan A Reiter M Zellweger C Meissner J Stelzig C Freese M Capodarve I Mueller C 《The American journal of cardiology》2012,109(8):1117-1123
We hypothesized that midregional pro-A-type natriuretic peptide (MR-proANP), the stable midregional epitope of proANP, might be useful in the early diagnosis and risk stratification of patients with suspected acute myocardial infarction (AMI). In this multicenter study we measured MR-proANP, cardiac troponin T (cTnT), and high-sensitive cTnT (hs-cTnT) at presentation in 675 consecutive patients presenting to the emergency department with suspected AMI. The final diagnosis was adjudicated by 2 independent cardiologists. Patients were followed 360 days for mortality and AMI. AMI was the final diagnosis in 119 patients (18%). Median MR-proANP levels at presentation were significantly higher in patients with AMI (189 pmol/L, interquartile range 97 to 341) versus patients with another final diagnosis (83 pmol/L, 49 to 144, p <0.001). However, neither the combination of MR-proANP with cTnT nor its combination with hs-cTnT significantly improved diagnostic accuracy as quantified by area under the receiver operating characteristic curve (0.91 vs 0.89 for cTnT alone, p = 0.086; 0.95 vs 0.96 for hs-cTnT, respectively, p = 0.02). Cumulative 360-day mortality/AMI rates were 2.4% in the first, 3.6% in the second, 9.5% in the third, and 18.8% in the fourth quartiles of MR-proANP (p <0.001). MR-proANP (area under the curve 0.76) predicted mortality/AMI independently of and more accurately than cTnT (area under the curve 0.62), hs-cTnT (area under the curve 0.71), and Thrombolysis In Myocardial Infarction risk score (area under the curve 0.72). Net reclassification improvements offered by the additional use of MR-proANP were 0.388 (p <0.001), 0.425 (p <0.001), and 0.217 (p = 0.007), respectively. In conclusion, MR-proANP improves risk prediction for 360-day mortality/AMI but does not seem to help in the early diagnosis of AMI. 相似文献
138.
M Burns M Rowland R N'guessan I Carneiro A Beeche SS Ruiz S Kamara W Takken P Carnevale R Allan 《The American journal of tropical medicine and hygiene》2012,87(2):242-250
Abstract. A double-blind phase III malaria prevention trial was conducted in two refugee camps using pre-manufactured insecticide-treated plastic sheeting (ITPS) or untreated polyethylene sheeting (UPS) randomly deployed to defined sectors of each camp. In Largo camp the ITPS or UPS was attached to inner walls and ceilings of shelters, whereas in Tobanda the ITPS or UPS was used to line only the ceiling and roof. In Largo the Plasmodium falciparum incidence rate in children up to 3 years of age who were cleared of parasites and monitored for 8 months was 163/100 person-years under UPS and 63 under ITPS (adjusted odds ratio [AOR] = 0.40, 95% confidence interval [CI] = 0.33-0.47). In Tobanda incidence was 157/100 person-years under UPS and 134 under ITPS (AOR = 0.85, 95% CI = 0.75-0.95). Protective efficacy was 61% under fully lined ITPS and 15% under roof lined ITPS. Anemia rates improved under ITPS in both camps. This novel tool proved to be a convenient, safe, and long-lasting method of malaria control when used as a full shelter lining in an emergency setting. 相似文献
139.
140.