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91.
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
92.
Permeabilization induced by lacticin 3147, lactococcins A, B and M, enterocin AS-48 and nisin, bacteriocins described as cell membrane-pore forming and lytic agents, enhanced in all cases aldehyde formation by Lactococcus lactis IFPL730. Nevertheless, the conversion of isoleucine into 2-methylbutyraldehyde depended not only on the degree of permeabilization but also on the bacteriocin that caused the cell membrane damage. The highest values of 2-methylbutyraldehyde corresponded to cell suspensions containing lacticin 3147 and lactococcins, treatments that provoked further lysis in addition to induced permeabilization. 相似文献
93.
Mutations in the fumarate hydratase gene cause hereditary leiomyomatosis and renal cell cancer in families in North America 总被引:10,自引:0,他引:10 下载免费PDF全文
Toro JR Nickerson ML Wei MH Warren MB Glenn GM Turner ML Stewart L Duray P Tourre O Sharma N Choyke P Stratton P Merino M Walther MM Linehan WM Schmidt LS Zbar B 《American journal of human genetics》2003,73(1):95-106
Hereditary leiomyomatosis and renal cell cancer (HLRCC) is an autosomal dominant disorder characterized by smooth-muscle tumors of the skin and uterus and/or renal cancer. Although the identification of germline mutations in the fumarate hydratase (FH) gene in European families supports it as the susceptibility gene for HLRCC, its role in families in North America has not been studied. We screened for germline mutations in FH in 35 families with cutaneous leiomyomas. Sequence analysis revealed mutations in FH in 31 families (89%). Twenty different mutations in FH were identified, of which 18 were novel. Of these 20 mutations, 2 were insertions, 5 were small deletions that caused frameshifts leading to premature truncation of the protein, and 13 were missense mutations. Eleven unrelated families shared a common mutation: R190H. Eighty-one individuals (47 women and 34 men) had cutaneous leiomyomas. Ninety-eight percent (46/47) of women with cutaneous leiomyomas also had uterine leiomyomas. Eighty-nine percent (41/46) of women with cutaneous and uterine leiomyomas had a total hysterectomy, 44% at age < or =30 years. We identified 13 individuals in 5 families with unilateral and solitary renal tumors. Seven individuals from four families had papillary type II renal cell carcinoma, and another individual from one of these families had collecting duct carcinoma of the kidney. The present study shows that mutations in FH are associated with HLRCC in North America. HLRCC is associated with clinically significant uterine fibroids and aggressive renal tumors. The present study also expands the histologic spectrum of renal tumors and FH mutations associated with HLRCC. 相似文献
94.
Aquino AC Jorge JA Terenzi HF Polizeli ML 《Applied microbiology and biotechnology》2003,61(4):323-328
An alpha-amylase produced by Scytalidium thermophilum was purified using DEAE-cellulose and CM-cellulose ion exchange chromatography and Sepharose 6B gel filtration. The purified protein migrated as a single band in 6% PAGE and 7% SDS-PAGE. The estimated molecular mass was 36 kDa (SDS-PAGE) and 49 kDa (Sepharose 6B). Optima of pH and temperature were 6.0 and 60 degrees C, respectively. In the absence of substrate the purified alpha-amylase was stable for 1 h at 50 degrees C and had a half-life of 12 min at 60 degrees C, but was fully stable in the presence of starch. The enzyme was not activated by several metal ions tested, including Ca(2+) (up to 10 mM), but HgCl(2 )and CuCl(2) inhibited its activity. The alpha-amylase produced by S. thermophilum preferentially hydrolyzed starch, and to a lesser extent amylopectin, maltose, amylose and glycogen in that order. The products of starch hydrolysis (up to 6 h of reaction) analyzed by thin layer chromatography, showed oligosaccharides such as maltotrioses, maltotetraoses and maltopentaoses. Maltose and traces of glucose were formed only after 3 h of reaction. These results confirm the character of the enzyme studied to be an alpha-amylase (1,4-alpha-glucan glucanohydrolase). 相似文献
95.
Barragán MJ Martínez S Marchal JA Bullejos M Díaz de la Guardia R Sánchez A 《Hereditas》2002,137(1):65-71
Repetitive DNA sequences represent a substantial component of eukaryotic genomes. These sequences have been described and characterized in many mammalian species. However, little information about repetitive DNA sequences is available in bat species. Here we describe an EcoRI family of repetitive DNA sequences present in the species Miniopterus schreibersi. These repetitive sequences are 57.85%, A-T rich, organized in tandem, and with a monomer unit length of 904 bp. Methylation analysis using the isoesquizomer pair MspI and HpaII indicates that the cytosines present in the sequences CCGG are partially methylated. Furthermore, Southern blot analysis demonstrated that these DNA sequences are absent in the genomes of four related microbat species and suggest that it could be specific to the M. schreibersi genome. 相似文献
96.
Limited overlapping roles of P15(INK4b) and P18(INK4c) cell cycle inhibitors in proliferation and tumorigenesis 总被引:11,自引:0,他引:11 下载免费PDF全文
Latres E Malumbres M Sotillo R Martín J Ortega S Martín-Caballero J Flores JM Cordón-Cardo C Barbacid M 《The EMBO journal》2000,19(13):3496-3506
Entry of quiescent cells into the cell cycle is driven by the cyclin D-dependent kinases Cdk4 and Cdk6. These kinases are negatively regulated by the INK4 cell cycle inhibitors. We report the generation of mice defective in P15(INK4b) and P18(INK4c). Ablation of these genes, either alone or in combination, does not abrogate cell contact inhibition or senescence of mouse embryo fibroblasts in culture. However, loss of P15(INK4b), but not of P18(INK4c), confers proliferative advantage to these cells and makes them more sensitive to transformation by H-ras oncogenes. In vivo, ablation of P15(INK4b) and P18(INK4c) genes results in lymphoproliferative disorders and tumor formation. Mice lacking P18(INK4c) have deregulated epithelial cell growth leading to the formation of cysts, mostly in the cortical region of the kidneys and the mammary epithelium. Loss of both P15(INK4b) and P18(INK4c) does not result in significantly distinct phenotypic manifestations except for the appearance of cysts in additional tissues. These results indicate that P15(INK4b) and P18(IKN4c) are tumor suppressor proteins that act in different cellular lineages and/or pathways with limited compensatory roles. 相似文献
97.
98.
Bessy Gutirrez Luis Osorio María Cristina M. Motta Telervo Huima-Byron Heydeie Erdjument-Bromage Christian Muoz Hernn Sagua Renato A. Mortara Alex Echeverría Jorge E. Araya Jorge Gonzlez 《Parasitology international》2009,58(4):367-374
Three different monoclonal antibodies were produced against Trypanosona cruzi proteasomes. These antibodies were shown to react with a single 27-kDa band on immunoblots of purified proteasomes. Using a 7E5 monoclonal antibody (IgG1) that recognized the α5 subunit of protozoan protease we have studied the intracellular distribution of the T. cruzi 20S proteasome. Contrary to all cell types described to date, T. cruzi 20S proteasome was found not only in the cytoplasm and nucleus but also in the kinetoplast. As revealed by confocal microscopy, the reactivity of monoclonal antibody 7E5 was highly specific for protozoan proteasome because the antibody recognized only the proteasomes from parasites and not those from the mammalian host in T. cruzi infected cells. These findings were confirmed by immunoblots or immunoprecipitations, followed by chymotrypsin-like activity detection in kinetoplasts isolated by differential centrifugation and sucrose density gradients. Proteasome 20S was present in all T. cruzi stages and only slight differences in terms of relative abundance were found. The potential role of the proteasome in kinetoplast remodeling remains to be determined. 相似文献
99.
Molecular characterization of American cockroach tropomyosin (Periplaneta americana allergen 7), a cross-reactive allergen 总被引:4,自引:0,他引:4
Asturias JA Gómez-Bayón N Arilla MC Martínez A Palacios R Sánchez-Gascón F Martínez J 《Journal of immunology (Baltimore, Md. : 1950)》1999,162(7):4342-4348
Inhalation of allergens produced by the American cockroach (Periplaneta americana) induces IgE Ab production and the development of asthma in genetically predisposed individuals. The cloning and expression in Escherichia coli of P. americana tropomyosin allergen have been achieved. The protein shares high homology with other arthropod tropomyosins (80% identity) but less homology with vertebrate ones (50% identity). The recombinant allergen was produced in E. coli as a nonfusion protein with a yield of 9 mg/l of bacterial culture. Both natural and recombinant tropomyosins were purified by isoelectric precipitation. P. americana allergen 1 (Per a 1) and Per a 7 (tropomyosin) are to date the only cross-reacting allergens found in cockroaches. ELISA and Western blot inhibition experiments, using natural and recombinant purified tropomyosins from shrimp and cockroach, showed that tropomyosin induced cross-reactivity of IgE from patients allergic to these allergens, suggesting that this molecule could be a common allergen among invertebrates. 相似文献
100.
Hernández-Montiel HL Meléndez-Herrera E Cepeda-Nieto AC Mejía-Viggiano C Larriva-Sahd J Guthrie S Varela-Echavarría A 《Developmental biology》2003,255(1):99-112
We have addressed the control of longitudinal axon pathfinding in the developing hindbrain, including the caudal projections of reticular and raphe neurons. To test potential sources of guidance signals, we assessed axon outgrowth from embryonic rat hindbrain explants cultured in collagen gels at a distance from explants of midbrain-hindbrain boundary (isthmus), caudal hindbrain, or cervical spinal cord. Our results showed that the isthmus inhibited caudally directed axon outgrowth by 80% relative to controls, whereas rostrally directed axon outgrowth was unaffected. Moreover, caudal hindbrain or cervical spinal cord explants did not inhibit caudal axons. Immunohistochemistry for reticular and raphe neuronal markers indicated that the caudal, but not the rostral projections of these neuronal subpopulations were inhibited by isthmic explants. Companion studies in chick embryos showed that, when the hindbrain was surgically separated from the isthmus, caudal reticulospinal axon projections failed to form and that descending pioneer axons of the medial longitudinal fasciculus (MLF) play an important role in the caudal reticulospinal projection. Taken together, these results suggest that diffusible chemorepellent or nonpermissive signals from the isthmus and substrate-anchored signals on the pioneer MLF axons are involved in the caudal direction of reticulospinal projections and might influence other longitudinal axon projections in the brainstem. 相似文献