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41.
Marc C. Tahita Halidou Tinto Annette Erhart Adama Kazienga Robert Fitzhenry Chantal VanOvermeir Anna Rosanas-Urgell Jean-Bosco Ouedraogo Robert T. Guiguemde Jean-Pierre Van geertruyden Umberto D’Alessandro 《PloS one》2015,10(9)
Background
The emergence and spread of drug resistance represents one of the biggest challenges for malaria control in endemic regions. Sulfadoxine-pyrimethamine (SP) is currently deployed as intermittent preventive treatment in pregnancy (IPTp) to prevent the adverse effects of malaria on the mother and her offspring. Nevertheless, its efficacy is threatened by SP resistance which can be estimated by the prevalence of dihydropteroate synthase (dhps) and dihydrofolate reductase (dhfr) mutations. This was measured among pregnant women in the health district of Nanoro, Burkina Faso.Methods
From June to December 2010, two hundred and fifty six pregnant women in the second and third trimester, attending antenatal care with microscopically confirmed malaria infection were invited to participate, regardless of malaria symptoms. A blood sample was collected on filter paper and analyzed by PCR-RFLP for the alleles 51, 59, 108, 164 in the pfdhfr gene and 437, 540 in the pfdhps gene.Results
The genes were successfully genotyped in all but one sample (99.6%; 255/256) for dhfr and in 90.2% (231/256) for dhps. The dhfr C59R and S108N mutations were the most common, with a prevalence of 61.2% (156/255) and 55.7% (142/255), respectively; 12.2% (31/255) samples had also the dhfr N51I mutation while the I164L mutation was absent. The dhps A437G mutation was found in 34.2% (79/231) isolates, but none of them carried the codon K540E. The prevalence of the dhfr double mutations NRNI and the triple mutations IRNI was 35.7% (91/255) and 11.4% (29/255), respectively.Conclusion
Though the mutations in the pfdhfr and pfdhps genes were relatively common, the prevalence of the triple pfdhfr mutation was very low, indicating that SP as IPTp is still efficacious in Burkina Faso. 相似文献42.
Ifedayo M. O. Adetifa Abdul Khalie Muhammad David Jeffries Simon Donkor Martien W. Borgdorff Tumani Corrah Umberto D’Alessandro 《PloS one》2015,10(10)
Background
A Tuberculin skin test (TST) survey was conducted to assess the prevalence of latent TB Infection (LTBI) and to estimate the annual risk of M. tuberculosis infection (ARTI) in Gambian school children. The results are expected to contribute to understanding of Tuberculosis epidemiology in The Gambia.Methods
This was a nationwide, multi-cluster survey in children aged 6–11 years. Districts, 20 of 37, were selected by probability proportional to size and schools by simple random sampling. All TST were performed using the Mantoux method. Height and weight measurements were obtained for all participants. We calculated prevalence of LTBI using cut-off points of 10mm, the mirror and mixture modelling methods.Results
TST readings were completed 13,386 children with median age of 9 years (interquartile range [IQR] 8–10 years). Mixture analysis yielded a cut-off point of 12 mm, and LTBI prevalence of 6.9% [95%CI 6.47–7.37] and the ARTI was 0.75% [95%CI 0.60–0.91]. LTBI was associated gender and urban residence (p <0.01). Nutritional status was not associated with non-reactive TST or sizes of TST indurations. ARTI did not differ significantly by age, gender, BCG vaccination or residence.Conclusions
This estimates for LTBI prevalence and ARTI were low but this survey provides updated data. Malnutrition did not affect estimates of LTBI and ARTI. Given the low ARTI in this survey and the overlapping distribution of indurations with mixture modelling, further surveys may require complementary tests such as interferon gamma release assays or novel diagnostic tools. 相似文献43.
Umberto Melia Montserrat Vallverdú Xavier Borrat Jose Fernando Valencia Mathieu Jospin Erik Weber Jensen Pedro Gambus Pere Caminal 《PloS one》2015,10(4)
The level of sedation in patients undergoing medical procedures evolves continuously, affected by the interaction between the effect of the anesthetic and analgesic agents and the pain stimuli. The monitors of depth of anesthesia, based on the analysis of the electroencephalogram (EEG), have been progressively introduced into the daily practice to provide additional information about the state of the patient. However, the quantification of analgesia still remains an open problem. The purpose of this work is to improve the prediction of nociceptive responses with linear and non-linear measures calculated from EEG signal filtered in frequency bands higher than the traditional bands. Power spectral density and auto-mutual information function was applied in order to predict the presence or absence of the nociceptive responses to different stimuli during sedation in endoscopy procedure. The proposed measures exhibit better performances than the bispectral index (BIS). Values of prediction probability of Pk above 0.75 and percentages of sensitivity and specificity above 70% were achieved combining EEG measures from the traditional frequency bands and higher frequency bands. 相似文献
44.
Mario Cappiello Roberta MoschiniFrancesco Balestri Umberto MuraAntonella Del-Corso 《Biochemical and biophysical research communications》2014
The possible preferential action exerted by an inhibitor on the transformation of one of two agonist substrates catalyzed by the same enzyme has recently been reported in studies on aldose reductase inhibition. This event was defined as “intra-site differential inhibition” and the molecules able to exert this action as “differential inhibitors”. This work presents some basic kinetic models describing differential inhibition. Using a simple analytic approach, the results show that differential inhibition can occur through either competitive or mixed type inhibition in which the inhibitor prevalently targets the free enzyme. The results may help in selecting molecules whose differential inhibitory action could be advantageous in controlling the activity of enzymes acting on more than one substrate. 相似文献
45.
Giuseppe Cannazza Marina M. Carrozzo Umberto Battisti Daniela Braghiroli Carlo Parenti Alessandro Troisi Luigino Troisi 《Chirality》2010,22(9):789-797
Benzothiadiazines differently substituted at the sulfonamidic nitrogen atom, at the stereogenic carbon atom and at the anilinic nitrogen atom have been synthesized and fully characterized. Enantioseparation of these compounds has revealed rapid on‐column enantiomerization. The recently developed software DCXplorer has been successfully applied to calculate enantiomerization kinetic parameters. Enantiomerization barriers of 3‐phenyl substituted benzothiadiazines, calculated in this work, have indicated a higher enantiomerization rate suggesting that the aromatic substituent exerts a strong effect on the enantiomerization process. Methyl substitution on N2 position led to higher free energy barriers of enantiomerization, suggesting negative influence of methyl in the N2 position on enantiomerization kinetics. However, methylation on N4 position increases the enantiomerization rates significantly. The results obtained have been employed to postulate an enantiomerization mechanism for chiral benzothiadiazine type compounds. Chirality 2010. © 2010 Wiley‐Liss, Inc. 相似文献
46.
Mariapaola Nitti Anna Lisa Furfaro Claudia Cevasco Nicola Traverso Umberto Maria Marinari Maria Adelaide Pronzato Cinzia Domenicotti 《Cellular signalling》2010,22(5):828-835
The role of reactive oxygen species (ROS) in the regulation of signal transduction processes has been well established in many cell types and recently the fine tuning of redox signalling in neurons received increasing attention. With regard to this, the involvement of NADPH oxidase (NOX) in neuronal pathophysiology has been proposed but deserves more investigation. In the present study, we used SH-SY5Y neuroblastoma cells to analyse the role of NADPH oxidase in retinoic acid (RA)-induced differentiation, pointing out the involvement of protein kinase C (PKC) delta in the activation of NOX. Retinoic acid induces neuronal differentiation as revealed by the increased expression of MAP2, the decreased cell doubling rate, and the gain in neuronal morphological features and these events are accompanied by the increased expression level of PKC delta and p67phox, one of the components of NADPH oxidase. Using DPI to inhibit NOX activity we show that retinoic acid acts through this enzyme to induce morphological changes linked to the differentiation. Moreover, using rottlerin to inhibit PKC delta or transfection experiments to overexpress it, we show that retinoic acid acts through this enzyme to induce MAP2 expression and to increase p67phox membrane translocation leading to NADPH oxidase activation. These findings identify the activation of PKC delta and NADPH oxidase as crucial steps in RA-induced neuroblastoma cell differentiation. 相似文献
47.
Magda Gioia Giovanni Francesco Fasciglione Susanna Monaco Riccardo Iundusi Diego Sbardella Stefano Marini Umberto Tarantino Massimo Coletta 《Journal of biological inorganic chemistry》2010,15(8):1219-1232
The proteolytic processing of collagen I by three matrix metalloproteinases (MMPs), a collagenase (MMP-1), a gelatinase (MMP-2),
and the ectodomain of a membrane-type metalloproteinase (MMP-14), has been investigated at 37 °C between pH 6.0 and 9.2, a
pH range reflecting conditions found in different body compartments under various physiopathological processes. In the proteolytic
degradation the native collagen triple helix must be partially unwound to allow the binding of α chains to the protease’s
active-site cleft. We have found that MMP-1 interacts with the two types of collagen I α chains in a similar fashion, whereas
both MMP-2 and MMP-14 bind the two α chains in a different way. The overall enzymatic activity is higher on the α-2 chain
for both MMP-1 and MMP-2, whereas the MMP-14 ectodomain preferentially cleaves the α-1 chain. In MMP-2 a marked difference
for substrate affinity (higher for the α-1 chain) is overwhelmed by an even more marked propensity to cleave the α-2 chain.
As a whole, the three classes of MMPs investigated appear to process collagen I in a significantly different fashion, so various
MMPs play different roles in the collagen homeostasis in various compartments (such as bloodstream, synovial fluid, normal
and tumoral tissues), where different pH values are observed. 相似文献
48.
Nicoletta Botto Simona Vittorini Giovanna Maria Colombo Andrea Biagini Umberto Paradossi Giovanni Aquaro Maria Grazia Andreassi 《Cardiovascular ultrasound》2010,8(1):1-5
Background
To assess the reliability of fetal heart volume measurement by three-dimensional sonography (3DUS) using the eXtended Imaging Virtual Organ Computer-aided AnaLysis (XI VOCAL) method.Methods
This reliability study enrolled 30 pregnant women with singleton healthy pregnancies between 19 and 34 weeks of gestation. All volume acquirements were performed with a convex volumetric transducer (C3-7ED) coupled to an Accuvix XQ sonography device (Medison, Korea). The XI VOCAL 10 planes was the method of choice for volumetric measurement. 3D datasets were analyzed by two observers (EQSB and HJFM); fetal heart volume was measured twice by the first and once by the second observer to calculate intra and interobserver reproducibility. Statistical analysis used pareated Student's t test (p) and calculated Intraclass correlation coefficients (ICC). Bland-Altman plots were also constructed.Results
We observed an excellent intra- and interobserver reliability for fetal cardiac volume assessed by XI VOCAL. For the intraobserver the ICC was 0.998 (95% CI: 0.997; 0.999), with mean of differences of 0.12 cm3 (95% limits of agreement: -0.84; +0.84; p = 0.130). For interobserver the ICC was 0.899 (95%CI: 0.996; 0.998), mean of differences 0.05 cm3 (95% limits of agreement: -0.84; +0.84; p = 0.175).Conclusion
Fetal cardiac volume assessed by 3DUS using XI VOCAL method is highly reproducible between 19 to 34 gestational weeks. 相似文献49.
Pelaia G Gallelli L D'Agostino B Vatrella A Cuda G Fratto D Renda T Galderisi U Piegari E Crimi N Rossi F Caputi M Costanzo FS Vancheri C Maselli R Marsico SA 《Journal of cellular physiology》2007,210(2):489-497
Transforming growth factor-beta1 (TGF-beta1) is crucially involved in the fibrotic events characterizing interstitial lung diseases (ILDs), as well as in the airway remodeling process typical of asthma. Within such a context, the aim of our study was to investigate, in primary cultures of normal and fibrotic human lung fibroblasts (HLFs), the effects of TGF-beta1 on mitogen-activated protein kinase (MAPK) phosphorylation, cell proliferation, and production of interleukins 6 (IL-6) and 11 (IL-11), in the presence or absence of a pretreatment with budesonide (BUD). MAPK phosphorylation was detected by Western blotting, cell viability and proliferation were evaluated using Trypan blue staining and [(3)H]-thymidine incorporation assay, respectively, and the release of IL-6 and IL-11 into cell culture supernatants was assessed by ELISA. TGF-beta1 (10 ng/ml) significantly stimulated MAPK phosphorylation (P < 0.01), and also enhanced cell proliferation as well as the secretion of both IL-6 and IL-11, which reached the highest increases at the 72nd h of cell exposure to this growth factor. All such effects were prevented by BUD (10(-8) M) and, with the exception of IL-6 release, also by a mixture of MAPK inhibitors. Therefore, our findings suggest that the fibrotic action exerted by TGF-beta1 in the lung is mediated at least in part by MAPK activation and by an increased synthesis of the profibrogenic cytokines IL-6 and IL-11; all these effects appear to be prevented by corticosteroids via inhibition of MAPK phosphorylation. 相似文献
50.
Giovanna Lalatta-Costerbosa Maurizio Mazzoni Paolo Clavenzani Giovanni Di Guardo Gemma Mazzuoli Giuseppe Marruchella Luigi De Grossi Umberto Agrimi Roberto Chiocchetti 《The journal of histochemistry and cytochemistry》2007,55(4):387-401
Until now, significant differences in the neurochemical pattern of enteric neurons have been demonstrated in all species studied; however, some strong similarities also occur across species, such as the occurrence of nitric oxide synthase immunoreactivity (NOS-IR) in inhibitory motor neurons to muscle. In consideration of the insufficient data regarding the enteric nervous system (ENS) of sheep, we investigated the myenteric plexus and submucosal plexus of the ovine ileum. Since the pivotal role of the ENS in the early pathogenesis of sheep scrapie, the "prototype" of prion diseases, has been suggested, we have focused our observations also on the host's PrP genotype. We have studied the morphology and distribution of NOS-IR neurons and their relationships with the enteric glia in whole-mount preparations and in cryostat sections. NOS-IR neurons, always encircled by glial processes, were located in both plexuses. Many NOS-IR fibers were seen in the circular muscle layer, in the submucosa, and in the mucosa. In the submucosa they were close to the lymphoid tissue. No differences in the distribution and percentage of NOS-IR fibers and neurons were observed among sheep carrying different PrP genotype, thus making unlikely their contribution in the determinism of susceptibility/resistance to scrapie infection. 相似文献