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21.
Nasser Fardousi Everton Nunes da Silva Roxanne Kovacs Josephine Borghi Jorge O. M. Barreto Sren Rud Kristensen Juliana Sampaio Helena Eri Shimizu Luciano B. Gomes Letícia Xander Russo Garibaldi D. Gurgel Timothy Powell-Jackson 《PLoS medicine》2022,19(7)
BackgroundPay-for-performance (P4P) programmes to incentivise health providers to improve quality of care have been widely implemented globally. Despite intuitive appeal, evidence on the effectiveness of P4P is mixed, potentially due to differences in how schemes are designed. We exploited municipality variation in the design features of Brazil’s National Programme for Improving Primary Care Access and Quality (PMAQ) to examine whether performance bonuses given to family health team workers were associated with changes in the quality of care and whether the size of bonus mattered.Methods and findingsFor this quasi-experimental study, we used a difference-in-differences approach combined with matching. We compared changes over time in the quality of care delivered by family health teams between (bonus) municipalities that chose to use some or all of the PMAQ money to provide performance-related bonuses to team workers with (nonbonus) municipalities that invested the funds using traditional input-based budgets. The primary outcome was the PMAQ score, a quality of care index on a scale of 0 to 100, based on several hundred indicators (ranging from 598 to 660) of health care delivery. We did one-to-one matching of bonus municipalities to nonbonus municipalities based on baseline demographic and economic characteristics. On the matched sample, we used ordinary least squares regression to estimate the association of any bonus and size of bonus with the prepost change over time (between November 2011 and October 2015) in the PMAQ score. We performed subgroup analyses with respect to the local area income of the family health team. The matched analytical sample comprised 2,346 municipalities (1,173 nonbonus municipalities; 1,173 bonus municipalities), containing 10,275 family health teams that participated in PMAQ from the outset. Bonus municipalities were associated with a 4.6 (95% CI: 2.7 to 6.4; p < 0.001) percentage point increase in the PMAQ score compared with nonbonus municipalities. The association with quality of care increased with the size of bonus: the largest bonus group saw an improvement of 8.2 percentage points (95% CI: 6.2 to 10.2; p < 0.001) compared with the control. The subgroup analysis showed that the observed improvement in performance was most pronounced in the poorest two-fifths of localities. The limitations of the study include the potential for bias from unmeasured time-varying confounding and the fact that the PMAQ score has not been validated as a measure of quality of care.ConclusionsPerformance bonuses to family health team workers compared with traditional input-based budgets were associated with an improvement in the quality of care.Nasser Fardousi and colleagues investigate the association between performance bonuses and the quality of primary health care delivered by family health teams in Brazil. 相似文献
22.
Regulation of AMPA Receptor Activity, Synaptic Targeting and Recycling: Role in Synaptic Plasticity 总被引:7,自引:0,他引:7
The alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors for the neurotransmitter glutamate are oligomeric structures responsible for most fast excitatory responses in the central nervous system. The activity of AMPA receptors can be directly regulated by protein phosphorylation, which may also affect the interaction with intracellular proteins and, consequently, their recycling and localization to defined postsynaptic sites. This review focuses on recent advances in understanding the dynamic regulation of AMPA receptors, on a short- and long-term basis, and its implications in synaptic plasticity. 相似文献
23.
Chitin was functionalized with hexamethylenediamine followed by glutaraldehyde activation, and its capacity to bind Candida rugosa lipase was investigated. The loading of 250 units g(-1) support showed to be effective, resulting in a uniform enzyme fixation with high catalytic activity. Both free and immobilized lipases were characterized by determining the activity profile as a function of pH, temperature, and thermal stability. For the immobilized lipase, the influence of the reaction temperature and substrate polarity in nonconventional biocatalysis was also analyzed. Production of butyl esters was found to be dependent on the substrate partition coefficient, which accounts the greatest value for the system butanol and butyric acid. The highest enzyme activity was found for the system butanol and caprylic acid at a reaction temperature of 40 degrees C. Under such conditions, the operational stability tests indicated that a small enzyme deactivation occurs after 12 batches, revealing a biocatalyst half-life of 426.7 h. 相似文献
24.
Gomes CM Goto H Magnanelli AC Monteiro HP Soares RP Corbett CE Gidlund M 《Experimental parasitology》2001,99(4):190-197
Insulin-like growth factor (IGF)-I constitutively present in the skin is one of the first growth factors that Leishmania parasites encounter after transmission to the vertebrate host. We have previously shown that IGF-I is a potent growth-promoting factor for Leishmania parasites. IGF-I binds specifically to a single-site putative receptor at the parasite membrane, triggering a cascade of phosphorylation reactions. In the present article we characterize the receptor for IGF-I on Leishmania (Leishmania) mexicana promastigotes. The receptor is a monomeric glycoprotein with a molecular mass of 65 kDa and is antigenically related to the alpha chain of human type 1 IGF-I receptor. Upon IGF-I stimulation the receptor undergoes autophosphorylation on tyrosine residues with activation of its signaling pathway. Activation of the IGF-I receptor also leads to phosphorylation of an 185-kDa molecule that is homologous to the substrate of the insulin receptor present in human cells, the insulin receptor substrate 1 (IRS-1). 相似文献
25.
Hepatitis B and C in the hemodialysis unit of Tocantins,Brazil: serological and molecular profiles 总被引:1,自引:0,他引:1
Souza KP Luz JA Teles SA Carneiro MA Oliveira LA Gomes AS Dias MA Gomes SA Yoshida CF Martins RM 《Memórias do Instituto Oswaldo Cruz》2003,98(5):599-603
A survey was conducted in the hemodialysis population of the state of Tocantins, Brazil, aiming to assess the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, to analyze associated risk factors, and also to investigate these viruses genotypes distribution. During January and March 2001, all patients (n = 100) were interviewed at the unique dialysis unit in Tocantins. Blood samples were collected and serum samples were screened for HBV serological markers. Hepatitis B surface antigen positive samples were tested for HBV DNA. All samples were also tested for anti-HCV antibodies and HCV RNA. An overall prevalence of 45% was found for HBV infection (4% were HBsAg/anti-HBc positive, 2% were anti-HBc only and 39% had anti-HBc/anti-HBs markers). Concerning HCV infection, anti-HCV and HCV RNA were detected in 13% and 14% of the subjects, respectively. Three patients were HCV RNA positive and anti-HCV negative, resulting in an overall HCV prevalence of 16%. Univariate analysis of risk factors showed that only shift and length of tile on hemodialysis were associated with HBV and HCV positivity respectively. Among the four HBsAg-positive samples, HBV DNA was detected in three of them, which were identified as genotype A by restriction fragment length polymorphism (RFLP) analysis. All 14HCV RNA-positive samples were genotyped by INNO-LiPA. Genotypes la and 3a were found in 85% and 15%, respectively. The present data show low HBsAg and HCV prevalence rates. The risk factors associated with HBV and HCV positivity suggest that nosocomial transmission may influence in spreading these viruses in the dialysis unit studied. 相似文献
26.
Maria I. B. de Oliveira Lorena V. de Matos Lídia A. da Silva Edsandra C. Chagas Grazyelle S. da Silva Ana L. S. Gomes 《Journal of fish biology》2019,94(4):648-659
The objective of the present study was to describe the histology and histochemistry of the mucosal layer of the digestive tube of Piaractus brachypomus, and the histopathology associated with parasitism by Neoechinorhynchus sp. The digestive tube of P. brachypomus consists of three macroscopically distinct portions: short, rectilinear and elastic-walled ooesophagus, J-shaped siphon stomach and a long intestine with rectilinear and curved portions, defined by patterns of villi as foregut, midgut, and hindgut. Histological and histochemical differences were observed in the mucosal layers of the different digestive tube regions, such as intense production of neutral and acidic mucous substances in the pseudostratified mucosal epithelium of the oesophagus; positive periodic acid Schiff reagent (PAS)reactions at the apex of the columnar epithelial cells of the stomach and increased intensity of histochemical reactions in the hindgut region. Neoechinorhynchus sp. was present in 85.7% of specimens examined, with a mean intensity of 7.4 ± 6.2 (±) and abundance of 6.33. Good health of the fish indicated by high relative condition factor values ( Kn) and occurrence of only mild to moderate alteration in the mucosal layer indicated that Neoechinorhynchus sp. exhibits low pathogenicity towards P. brachypomus hosts in farming environments, with low levels of infection. 相似文献
27.
A Basu A Gomes A Gomes S C Dasgupta S C Lahiri 《Indian journal of experimental biology》1990,28(5):451-454
Toxin-L a lethal neuromuscular blocking agent was isolated from the venom of the scorpion, Lychas laevifrons (Pocock), by the CM-cellulose ion-exchange chromatography. It was a homogenous, thermolabile and low molecular weight protein. The toxin produced irreversible blockade of indirect stimulation induced twitch responses on innervated rat phrenic nerve-diaphragm and chick biventer cervicis preparation. The toxin did not produce any contractile response on toad rectus abdominis muscle preparation. On chronically denervated rat diaphragm, the toxin failed to alter the responses induced by direct stimulation, exogenous acetylcholine, potassium chloride and caffeine. Acetylcholine and carbachol induced contractions on isolated chick biventer cervicis remained unaltered by the toxin. Neostigmine failed to alter toxin induced neuromuscular blockade on innervated rat diaphragm. The toxin released a significant amount of acetylcholine from innervated rat diaphragm. It may be concluded that the toxin acts presynaptically through the release of acetylcholine, thereby producing neuromuscular blockade. 相似文献
28.
Fungal‐host diversity among mycoheterotrophic plants increases proportionally to their fungal‐host overlap 下载免费PDF全文
Sofia I. F. Gomes Vincent S. F. T. Merckx Serguei Saavedra 《Ecology and evolution》2017,7(10):3623-3630
The vast majority of plants obtain an important proportion of vital resources from soil through mycorrhizal fungi. Generally, this happens in exchange of photosynthetically fixed carbon, but occasionally the interaction is mycoheterotrophic, and plants obtain carbon from mycorrhizal fungi. This process results in an antagonistic interaction between mycoheterotrophic plants and their fungal hosts. Importantly, the fungal‐host diversity available for plants is restricted as mycoheterotrophic interactions often involve narrow lineages of fungal hosts. Unfortunately, little is known whether fungal‐host diversity may be additionally modulated by plant–plant interactions through shared hosts. Yet, this may have important implications for plant competition and coexistence. Here, we use DNA sequencing data to investigate the interaction patterns between mycoheterotrophic plants and arbuscular mycorrhizal fungi. We find no phylogenetic signal on the number of fungal hosts nor on the fungal hosts shared among mycoheterotrophic plants. However, we observe a potential trend toward increased phylogenetic diversity of fungal hosts among mycoheterotrophic plants with increasing overlap in their fungal hosts. While these patterns remain for groups of plants regardless of location, we do find higher levels of overlap and diversity among plants from the same location. These findings suggest that species coexistence cannot be fully understood without attention to the two sides of ecological interactions. 相似文献
29.
This study compared the antinociceptive effect produced by cathodic iontophoresis of sodium diclofenac close to an arthritic knee-joint in rats with that of systemic application. Arthritic nocifensive incapacitation was induced by LPS (1 microg) injection into a knee-joint previously (72 h) primed with carrageenan (300 microg). Diclofenac (0.1, 0.25 and 0.5 mg/kg) given intraperitoneally 1 h after LPS injection caused dose-dependent inhibition of incapacitation. Diclofenac iontophoresis was performed by varying either the current density (0.1, 0.2, and 0.3 mA/cm2) or the duration of application (4, 10, 20 and 30 min) of a polyvinylpirrolydone-hydroxymethylcellulose gel containing 1% sodium diclofenac. A clear, current density-dependent effect was observed for 0.1, 0.2 and 0.3 mA/cm2 (10 min period), which was similar to the effect observed for the intraperitoneal application of 0.1, 0.25 and 0.5 mg/kg doses. Combining different application periods with different current densities, in a manner that resulted in the same total current (1.6 mA*min) application, did not produce similar therapeutic effects, but the antinociceptive effect was directly proportional to the current density. The ipsilateral iontophoresis (0.25 mA/cm2 x 10 min or 0.5 mA/cm2 x 4 min) of diclofenac produced an effect significantly greater than the same contralateral application (p<0.05). In conclusion, our results suggest that the therapeutic effect depends on the current density but not on the application time, and also that the iontophoretic, direct application to the inflamed knee-joint enhances the therapeutic effect probably as a result of the direct delivery of the drug. 相似文献