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91.
Fernanda Valentini Murilo Souza Luz Noéli Boscato Tatiana Pereira-Cenci 《Journal of dentistry》2013,41(5):420-427
ObjectivesThis randomised clinical trial assessed how biofilm development and composition is affected by time and denture material type in denture wearers with and without denture stomatitis.MethodsSpecimens of acrylic resin (control) and denture liners (silicone-based or acrylic resin based, depending on the experimental phase) were inserted into the surface intaglio of 30 denture wearers. Biofilm was formed in two phases of 21 days, and counts of viable micro-organisms in the accumulating biofilm were determined after 7, 14 and 21days of biofilm formation. Data were analysed by three-way ANOVA followed by Tukey test to assess differences among health condition (healthy or with denture stomatitis), materials and time point.ResultsNon-albicans Candida species counts were higher in diseased patients with silicone-based denture liners (p = 0.01). Denture stomatitis patients showed higher mutans streptococci counts after 7 days (p = 0.0041).ConclusionsLonger biofilm formation time periods did not result in differences on biofilm composition. The denture liners evaluated in this study accumulate greater amount of biofilm, and therefore their use should be carefully planned.Clinical significanceThe silicone-based denture liner tested should be used cautiously in patients with denture stomatitis as it showed increased non-albicans species counts, known to be difficult to treat. 相似文献
92.
Fernanda Hansen Daniela Fraga de Souza Simone da Luz Silveira Ana Lúcia Hoefel Júlia Bijoldo Fontoura Ana Carolina Tramontina Larissa Daniele Bobermin Marina Concli Leite Marcos Luiz Santos Perry Carlos Alberto Gon?alves 《Metabolic brain disease》2012,27(4):531-539
Methylglyoxal is a dicarbonyl compound that is physiologically produced by enzymatic and non-enzymatic reactions. It can lead to cytotoxicity, which is mainly related to Advanced Glycation End Products (AGEs) formation. Methylglyoxal and AGEs are involved in the pathogenesis of Neurodegenerative Diseases (ND) and, in these situations, can cause the impairment of energetic metabolism. Astroglial cells play critical roles in brain metabolism and the appropriate functioning of astrocytes is essential for the survival and function of neurons. However, there are only a few studies evaluating the effect of methylglyoxal on astroglial cells. The aim of this study was to evaluate the effect of methylglyoxal exposure, over short (1 and 3?h) and long term (24?h) periods, on glucose, glycine and lactate metabolism in C6 glioma cells, as well as investigate the glyoxalase system and AGEs formation. Glucose uptake and glucose oxidation to CO2 increased in 1?h and the conversion of glucose to lipids increased at 3?h. In addition, glycine oxidation to CO2 and conversion of glycine to lipids increased at 1?h, whereas the incorporation of glycine in proteins decreased at 1 and 3?h. Methylglyoxal decreased glyoxalase I and II activities and increased AGEs content within 24?h. Lactate oxidation and lactate levels were not modified by methylglyoxal exposure. These data provide evidence that methylglyoxal may impair glucose metabolism and can affect glyoxalase activity. In periods of increased methylglyoxal exposure, such alterations could be exacerbated, leading to further increases in intracellular methylglyoxal and AGEs, and therefore triggering and/or worsening ND. 相似文献
93.
Berti SL Nasi GM Garcia C Castro FL Nunes ML Rojas DB Moraes TB Dutra-Filho CS Wannmacher CM 《Metabolic brain disease》2012,27(1):79-89
Phenylketonuria is characterized by a variable degree of mental retardation and other neurological features whose mechanisms
are not fully understood. In the present study we investigated the effect of intrahippocampal administration of phenylalanine,
isolated or associated with pyruvate or creatine, on rat behavior and on oxidative stress. Sixty-day-old male Wistar rats
were randomly divided into 6 groups: saline; phenylalanine; pyruvate; creatine; phenylalanine + pyruvate; phenylalanine +
creatine. Phenylalanine was administered bilaterally in the hippocampus one hour before training; pyruvate, at the same doses,
was administered in the hippocampus one hour before phenylalanine; creatine was administered intraperitoneally twice a day
for 5 days before training; controls received saline solution at same volumes than the other substances. Parameters of exploratory
behavior and of emotionality were assessed in both training and test sessions in the open field task. Rats receiving phenylalanine
did not habituate to the open field along the sessions, indicating deficit of learning/memory, but parameters of emotionality
were normal, not interfering in the habituation process. Pyruvate or creatine administration prevented the lack of habituation
caused by phenylalanine. Pyruvate and creatine also prevented alterations provoked by phenylalanine on lipid peroxidation,
total content of sulfhydryls, total radical-trapping antioxidant potential and total antioxidant reactivity. The results suggest
that the behavioral alterations provoked by intra-hippocampal administration of phenylalanine may be caused, at least in part,
by oxidative stress and/or energy deficit. If this also occurs in PKU, it is possible that pyruvate and creatine supplementation
to the phenylalanine-restricted diet might be beneficial to phenylketonuric patients. 相似文献
94.
Martínez-Avilés L Alvarez-Larrán A Besses C Navarro G Torres E Longarón R Angona A Pedro C Florensa L Serrano S Bellosillo B 《Annals of hematology》2012,91(10):1555-1562
JAK2V617F-negative essential thrombocythemia (ET) is a heterogeneous disease including clonal cases and others without evidence of clonality. However, it is unknown if the detection of myeloid clonality in JAK2V617F-negative ET patients confers a different clinical outcome than those in whom clonal hematopoiesis cannot be demonstrated. The objective of the present study was to evaluate the clinical significance of clonality assessment in patients with JAK2V617F-negative ET. Clonality investigation including mutational status of MPL, TET2, and ASXL1 genes and human androgen receptor (HUMARA) assay was performed in 73 JAK2V617F-negative cases out of 186 subjects consecutively diagnosed with ET in a single institution, at diagnosis or during follow-up. Mutations in MPL, TET2, and ASXL1 were observed in 7, 4, and 2 cases, respectively, whereas clonality by HUMARA assay was demonstrated in 21 out of 46 (46?%) female patients. With a median follow-up of 8?years, death, thrombosis, bleeding, and disease transformation were registered in 7, 10, 8, and 6 patients, respectively. No differences in thrombosis, bleeding or survival were observed according to clonality assessment. The probability of disease transformation at 10?years was higher in patients showing clonal hematopoiesis by presenting mutations in either MPL, TET2, or ASXL1 (64 versus 2?% in patients without mutations, p?0.001) and in those with HUMARA clonality (35 versus 0?% in patients with polyclonal hematopoiesis, p?0.004). In conclusion, disease transformation is associated with evidence of clonality in JAK2V617F-negative ET. 相似文献
95.
GJ Ruiz-Delgado D Gómez-Almaguer LC Tarín-Arzaga OG Cantú-Rodriguez CA Urdaneta U Rodríguez-Morales J Calderón-Garcia O Fernández-Vargas M Montes-Montiel M Sánchez-Cárdenas GJ Ruiz-Argüelles 《Hematology (Amsterdam, Netherlands)》2012,17(4):193-197
Rituximab (R) has changed the prognosis of patients with non-Hodgkin's lymphoma (NHL) in developed countries, but its role has not been analyzed in underprivileged circumstances. One hundred and two patients with NHL treated in a developing country were analyzed: 28 patients with follicular lymphoma (FL) and 74 with diffuse large B-cell lymphoma (DLCL). Patients were treated upfront with either cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or R-CHOP; the decision to employ R depending solely on the ability of patients to defray it. In DLCL, 42 were given CHOP and 32 R-CHOP, whereas in FL, 19 were given CHOP and 9 R-CHOP. The impact of the addition of R was found to be clearer in FL than in DLCL. In patients with DLCL, the overall survival (OS) was 87% at 80 months for those treated with R-CHOP and 84% at 145 months for those treated with CHOP (not significant). In patients with FL, the OS was 89% at 88 months for those treated with R-CHOP and 71% at 92 months for those treated with CHOP (P = 0··05). In a multivariate analysis, other variables which were identified to be associated with the OS were IPI and number of cycles in DLCL. It is concluded that R produced a mild positive impact in the OS of patients with FL, but not in those with DLCL. Since the addition of R results in a 36-fold increase in treatment costs, these observations may be important to decide therapeutic approaches in NHL patients living in underprivileged circumstances. 相似文献
96.
Ruiz-Delgado GJ Tarín-Arzaga LC Alarcón-Urdaneta C Calderón-García J Gómez-Almaguer D Ruiz-Argüelles GJ 《Hematology (Amsterdam, Netherlands)》2012,17(3):140-143
Twenty-nine consecutive patients with hairy cell leukemia (HCL) were treated in two institutions with interferon (IFN, n = 18) or cladribine (n = 11), between July 1987 and May 2011. Median age was 62 (range 29-83) years; there were 21 males and 8 females. Seven of the 18 patients in the IFN group (39%) achieved a complete remission (CR), whereas all the patients in the 2-CDA group entered a CR. Three patients in the 2-CDA group relapsed and needed an additional course of the drug, 2, 3 and 6 years after the initial one. The median overall survival (OS) of the whole group has not been reached, being above 217 months, the 217-month OS being 91%. The survival of patients treated with either IFN or 2-CDA was not statistically different (94% OS at 217 months versus 91% OS at 133 months, respectively). The data that we present here suggest that treatment of HCL with either 2-CDA or IFN is equally effective; treatment costs with IFN are substantially lower than those of the purine analog. 相似文献
97.
98.
Nuno Gomes Horácio Zenha Luís Azevedo Leonor Rios Hugo Sequeira Gustavo Coelho João Martins Cristina Pinto Diana Santos Maria da Luz Barroso Horácio Costa 《European journal of plastic surgery》2013,36(10):619-626
Introduction
The defect complexity and reconstructive options make the maxillary reconstruction a controversial theme and in a constant debate. The maxilla is a fundamental aesthetic and functional structure of the face. Microsurgical vascularized flaps replaced the usage of prosthetic material and pedicled flaps as a “gold standard” for the reconstruction of complex defects following maxillectomy.Methods
The authors report their experience of 24 maxillectomies with immediate microsurgical reconstruction, performed by the senior author (H.C.) between 1998 and 2011. They evaluate and classify the defects and the reconstructive options according to the classification system as proposed by Cordeiro and Santamaria in 2000, by a patient questionnaire and post-operative surgeon follow-up for the functional (diet, speech, and vision) and aesthetic end results.Results
There were no flap failures. The main etiology was squamous cell carcinoma and the most used flap was rectus abdominis free flap. Classes I and II were responsible for the cases in which the reconstructive algorithm was not followed. Most patients responded as having a normal diet, a nearly normal speech and unaffected vision. In a score of 1 to 5, the mean score in esthetic given by the patient was 3.62, while the mean score given by the surgeons was 4.13.Conclusions
Microsurgical reconstruction of maxillectomy defects with free flaps is the best reconstructive option, being the osteomyocutaneous flaps as the gold standard. Although with limited rehabilitation, good functional and aesthetic results are to be expected with myocutaneous flaps. The existence of an algorithm facilitates the classification and systematization of maxillary reconstruction. However, due to defect complexity and large number of reconstructive options, a perfect solution does not exist. The individual assessment of the patient and the defect always provides the best method for the reconstructive planning, mainly when choosing free flaps. Level of Evidence: Level IV, therapeutic study. 相似文献99.
Rita Nely Vilar Furtado Daniele Freitas Pereira Karine Rodrigues da Luz Marla Francisca dos Santos Monique Sayuri Konai Sonia de Aguiar Vilela Mitraud Andre Rosenfeld Artur da Rocha Correa Fernandes Jamil Natour 《REV BRAS REUMATOL》2013,53(6):476-482
ObjectiveCompare the effectiveness of ultrasound and fluoroscopy to guide intra-articular injections (IAI) in selected cases.Material and methodsA prospective study in our outpatient clinics at the Rheumatology Division at Universidade Federal de São Paulo (UNIFESP), Brazil, was conducted to compare the short-term (4 weeks) effectiveness of ultrasound and fluoroscopy-guided IAI in patients with rheumatic diseases. Inclusion criteria were: adults with refractory synovitis undergo- ing IAI with glucocorticoid. All patients had IAI performed with triamcinolone hexaceton- ide (20 mg/ml) with varying doses according to the joint injected.ResultsA total of 71 rheumatic patients were evaluated (52 women, 44 whites). Mean age was 51.9 ± 13 years and 47 of them (66.2%) were on regular DMARD use. Analysis of the whole sample (71 patients) and hip sub-analysis (23 patients) showed that significant im- provement was observed for both groups in terms of pain (P < 0.001). Global analysis also demonstrated better outcomes for patients in the FCG in terms of joint flexion (P < 0.001) and percentage change in joint flexion as compared to the USG. Likert scale score analyses demonstrated better results for the patients in the USG as compared to the FCG at the end of the study (P < 0.05). No statistically significant difference between groups was observed for any other study variable.Discussion and conclusionImaging-guided IAI improves regional pain in patients with vari- ous types of synovitis in the short term. For the vast majority of variables, no significant difference in terms of effectiveness was observed between fluoroscopy and ultrasound- guided IAI. 相似文献
100.
Georg R. Linke Stephanie Luz Joanna Janczak Andreas Zerz Bruno M. Schmied Ikbale Siercks René Warschkow Ulrich Beutner Ignazio Tarantino 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2013,398(1):139-145