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51.
Reinaldo de Menezes Martins Cristina de Albuquerque Possas Akira Homma 《Memórias do Instituto Oswaldo Cruz》2015,110(1):114-124
This paper presents, from the perspective of technological development and
production, the results of an investigation examining 61 clinical studies with
vaccines conducted in Brazil between 1938-2013, with the participation of the Oswaldo
Cruz Institute (IOC) and the Oswaldo Cruz Foundation (Fiocruz). These studies have
been identified and reviewed according to criteria, such as the kind of vaccine
(viral, bacterial, parasitic), their rationale, design and methodological strategies.
The results indicate that IOC and Fiocruz have accumulated along this time
significant knowledge and experience for the performance of studies in all clinical
phases and are prepared for the development of new vaccines products and processes.
We recommend national policy strategies to overcome existing regulatory and financing
constraints. 相似文献
52.
53.
54.
Arends S Brouwer E van der Veer E Groen H Leijsma MK Houtman PM Th A Jansen TL Kallenberg CG Spoorenberg A 《Arthritis research & therapy》2011,13(3):R94
Introduction
Identifying ankylosing spondylitis (AS) patients who are likely to benefit from tumor necrosis factor-alpha (TNF-α) blocking therapy is important, especially in view of the costs and potential side effects of these agents. Recently, the AS Disease Activity Score (ASDAS) has been developed to assess both subjective and objective aspects of AS disease activity. However, data about the predictive value of the ASDAS with respect to clinical response to TNF-α blocking therapy are lacking. The aim of the present study was to identify baseline predictors of response and discontinuation of TNF-α blocking therapy in AS patients in daily clinical practice. 相似文献55.
de Groot L Hinkema H Westra J Smit AJ Kallenberg CG Bijl M Posthumus MD 《Arthritis research & therapy》2011,13(6):R205
Introduction
Advanced glycation end products (AGEs) are produced and can accumulate during chronic inflammation, as might be present in patients with rheumatoid arthritis (RA). AGEs are involved in the development of cardiovascular disease. The aim of this study is to evaluate whether AGEs are increased in patients with long-standing RA and whether AGE accumulation is related to disease activity, disease severity and measures of (premature) atherosclerosis, such as endothelial activation, endothelial dysfunction and intima media thickness (IMT). 相似文献56.
Background
A recent study on expression and function of the ortholog of the Drosophila collier (col) gene in various arthropods including insects, crustaceans and chelicerates suggested a de novo function of col in the development of the appendage-less intercalary segment of insects. However, this assumption was made on the background of the now widely-accepted Pancrustacea hypothesis that hexapods represent an in-group of the crustaceans. It was therefore assumed that the expression of col in myriapods would reflect the ancestral state like in crustaceans and chelicerates, i.e. absence from the premandibular/intercalary segment and hence no function in its formation. 相似文献57.
Prema Menezes William C. Miller David A. Wohl Adaora A. Adimora Peter A. Leone William C. Miller Joseph J. Eron Jr. 《PloS one》2011,6(7)
Background
Patients who participate in clinical trials may experience better clinical outcomes than patients who initiate similar therapy within clinical care (trial effect), but no published studies have evaluated a trial effect in HIV clinical trials.Methods
To examine a trial effect we compared virologic suppression (VS) among patients who initiated HAART in a clinical trial versus in routine clinical care. VS was defined as a plasma HIV RNA ≤400 copies/ml at six months after HAART initiation and was assessed within strata of early (1996–99) or current (2000–06) HAART periods. Risk ratios (RR) were estimated using binomial models.Results
Of 738 persons initiating HAART, 30.6% were women, 61.7% were black, 30% initiated therapy in a clinical trial and 67% (n = 496) had an evaluable six month HIV RNA result. HAART regimens differed between the early and current periods (p<0.001); unboosted PI regimens (55.6%) were more common in the early and NNRTI regimens (46.4%) were more common in the current period. Overall, 78% (95%CI 74, 82%) of patients achieved VS and trial participants were 16% more likely to achieve VS (unadjusted RR 1.16, 95%CI 1.06, 1.27). Comparing trial to non-trial participants, VS differed by study period. In the early period, trial participants initiating HAART were significantly more likely to achieve VS than non-trial participants (adjusted RR 1.33; 95%CI 1.15, 1.54), but not in the current period (adjusted RR 0.98; 95%CI 0.87, 1.11).Conclusions
A clear clinical trial effect on suppression of HIV replication was observed in the early HAART period but not in the current period. 相似文献58.
Background
To determine the prevalence and associated factors with chronic kidney disease (CKD) in a cohort of HIV-positive individuals with undetectable viral load on HAART.Methods
From March, 2009 to September 2009, 213 individuals between 18-70 years, period on HAART ≥12 months, viral load < 50 copies/mm3, and CD4 ≥ 200 cells/mm3, were consecutively enrolled at the outpatient clinic of Hospital de Clínicas, Porto Alegre, Brazil. Exclusion criteria were obesity, malnourishment, amputee, paraplegic, previous history of renal disease, pregnancy and hepatic insufficiency. Renal function was determined by estimated glomerular filtration rate (eGFR) assessed by the modification of diet in renal disease. CKD was defined as an eGFR less or equal than 60 ml/min/1.73 m2, for a period of at least 3 months. Poisson regression was used to determine factors associated with CKD.Results
CKD was diagnosed in 8.4% of the population, and after adjustment, the risk factors were hypertension (RR = 3.88, 95%CI, 1.84 - 8.16), time on HAART (RR = 1.15, 95%CI,1.03–1.27) and tenofovir exposure (RR = 2.25, 95%CI, 1.04–4.95). Higher weight (RR = ,0.88 95%CI, 0.82–0.96) was associated to normal function.Conclusions
CKD was a common finding in this cohort of patients and was related to hypertension, time on HAART and tenofovir exposure. We suggest a more frequent monitoring of renal function, especially for those with risk factors to early identify renal impairment. 相似文献59.
Esbérard CE Martins-Hatano F Bittencourt EB Bossi DE Fontes A Lareschi M Menezes V Bergallo HG Gettinger D 《Memórias do Instituto Oswaldo Cruz》2005,100(7):761-764
Host-choice experiments were carried out with rodent and bat ectoparasites on Ilha Grande, state of Rio de Janeiro, Brazil. We constructed experimental chambers that enclosed three different rodent or bat host species, and then introduced a selected set of ectoparasitic arthropods. When given the opportunity to choose among host species, the ectoparasites showed a strong tendency to select their primary hosts, and reject novel host species. These kinds of simple experiments can be valuable tools for assessing the ability of ectoparasites to locate and discern differences between host species, and make choices about which hosts to infest, and which hosts to avoid. 相似文献
60.
Oliveira MF Kycia SW Gomez A Kosar AJ Bohle DS Hempelmann E Menezes D Vannier-Santos MA Oliveira PL Ferreira ST 《FEBS letters》2005,579(27):6010-6016
Hemozoin (Hz) is a heme crystal produced upon the digestion of hemoglobin (Hb) by blood-feeding organisms as a main mechanism of heme disposal. The structure of Hz consists of heme dimers bound by reciprocal iron-carboxylate interactions and stabilized by hydrogen bonds. We have recently described heme crystals in the blood fluke, Schistosoma mansoni, and in the kissing bug, Rhodnius prolixus. Here, we characterized the structures and morphologies of the heme crystals from those two organisms and compared them to synthetic β-hematin (βH). Synchrotron radiation X-ray powder diffraction showed that all heme crystals share the same unit cell and structure. The heme crystals isolated from S. mansoni and R. prolixus consisted of very regular units assembled in multicrystalline spherical structures exhibiting remarkably distinct surface morphologies compared to βH. In both organisms, Hz formation occurs inside lipid droplet-like particles or in close association to phospholipid membranes. These results show, for the first time, the structural and morphological characterization of natural Hz samples obtained from these two blood-feeding organisms. Moreover, Hz formation occurring in close association to a hydrophobic environment seems to be a common trend for these organisms and may be crucial to produce very regular shaped phases, allowing the formation of multicrystalline assemblies in the guts of S. mansoni and R. prolixus. 相似文献