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21.
Caio Nery Cibele Réssio Gerson de Azevedo Santa Cruz Rafael Silva Remor de Oliveira Carla Chertman 《Foot and Ankle Surgery》2013,19(4):276-282
BackgroundTo present the results of the treatment of hallux valgus with the proximal metatarsal opening wedge (PMOW) osteotomy using two different screw and plate systems.MethodsForty-one patients with moderate and severe hallux valgus were treated with the PMOW osteotomy between 2005 and 2009. The fixation was obtained by the Darco® BOW or by the Arthrex® LPS plate. Biplanar chevron and/or Akin osteotomy were associated according to the magnitude of distal angles. Each patient was evaluated with weight-bearing radiographs and AOFAS score.ResultsThe HV, IM, DMA and IP angles improved by a mean of 14°, 8°, 11°, 7° respectively. The sesamoid position improved in 79% of the feet. AOFAS score improved from a mean of 50 to 82.ConclusionThe PMOW osteotomy is effective to correct high-level hallux valgus deformities. Both systems guarantee the stability and correction of the osteotomy site. The combination with distal procedures is advisable to correct distal angles. 相似文献
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The invasion of erythrocytes by Plasmodium falciparum occurs through multiple pathways that can be studied in vitro by examining the invasion of erythrocytes treated with enzymes such as neuraminidase, trypsin, and chymotrypsin. We have studied the invasion pathways used by 31 Kenyan P. falciparum isolates from children with uncomplicated or severe malaria. Six distinct invasion profiles were detected, out of eight possible profiles. The majority of isolates (23 of 31) showed neuraminidase-resistant, trypsin-sensitive invasion, characteristic of the pathway mediated by an unknown parasite ligand and erythrocyte receptor "X." The neuraminidase-sensitive, trypsin-sensitive phenotype consistent with invasion mediated by the binding of parasite ligand erythrocyte binding antigen 175 to glycophorin A, the most common invasion profile in a previous study of Gambian field isolates, was seen in only 3 of 31 Kenyan isolates. No particular invasion profile was associated with severe P. falciparum malaria, and there was no significant difference in the levels of inhibition by the various enzyme treatments between isolates from children with severe malaria and those from children with uncomplicated malaria (P, >0.1 for all enzymes; Mann-Whitney U test). These results do not support the hypothesis that differences in invasion phenotypes play an important role in malaria virulence and indicate that considerable gaps remain in our knowledge of the molecular basis of invasion pathways in natural P. falciparum infections. 相似文献
24.
Barquinero J; Kiem HP; von Kalle C; Darovsky B; Goehle S; Graham T; Seidel K; Storb R; Schuening FG 《Blood》1995,85(5):1195-1201
We have studied the role of different conditioning regimens for engraftment of genetically marked hematopoietic repopulating cells in dogs. Peripheral blood (PB) and/or marrow cells collected after treatment with recombinant canine stem cell factor (rcSCF) or cyclophosphamide were transduced in a vector-containing long-term culture system. Three different vector-producing cell lines with similar viral titers were used. In two of them, the neo-containing LN vector was packaged either in the PA317 cell line with an amphotropic murine retrovirus envelope or the PG13 cell line with the gibbon ape leukemia virus (GALV) envelope. The MFG/GC vector produced in PA317 cells contained the human glucocerebrosidase gene. Nineteen dogs received either no conditioning (group A, n = 5), irradiation to both humeri with 1,000 cGy (group B, n = 5), a sublethal dose of cyclophosphamide 40 mg/kg (group C, n = 4), a sublethal dose of 200 or 300 cGy total body irradiation (TBI) (group D, n = 3), or an otherwise lethal dose of 920 cGy TBI (group E, n = 3) before intravenous (groups A, C, D, E) or intramedullary (group B) infusion of the transduced autologous hematopoietic cells. Transduction efficiency of hematopoietic cells at the time of infusion into the animals was similar among the different conditioning groups. Dogs were observed for at least 6 months. PB granulocytes were obtained at least every 3 weeks after transplant and analyzed by polymerase chain reaction for the presence of the transduced genes. The percentages of positive results in dogs more than 4 weeks after transplantation were 0% without conditioning, 5% with local irradiation, 18% with sublethal cyclophosphamide, 33% with sublethal TBI, and 17% with otherwise lethal TBI. Analyzing the influence of conditioning regimens by a generalized estimating equation (GEE) technique, which considered the use of different retrovirus vectors and the number of mononuclear cells infused as potential confounding variables, we found that engraftment of genetically marked repopulating cells was significantly improved (P < .001) in dogs receiving systemic conditioning with either otherwise lethal TBI, sublethal TBI, or sublethal cyclophosphamide compared to dogs with local irradiation only or no conditioning. Within the limitation of the experimental design, these data suggest that myeloablative or myelosuppressive conditioning improves engraftment of genetically marked hematopoietic repopulating cells. 相似文献
25.
Storb R; Raff RF; Appelbaum FR; Deeg HJ; Graham TC; Schuening FG; Shulman H; Yu C; Bryant E; Burnett R 《Blood》1994,84(10):3558-3566
Previous studies found that bone marrow (BM) allografts from DLA- identical littermates resulted in survival of two thirds of recipient dogs after otherwise lethal doses of 450 to 600 cGy of total body irradiation (TBI) because of successful allografts or autologous recovery after rejection of the allografts. The current study asked whether survival could be further improved by treating allograft recipients with recombinant canine granulocyte colony-stimulating factor (G-CSF), stem cell factor (SCF), or G-CSF/SCF. Of 21 dogs, 14 (67%) receiving allografts but no growth factors survived, 10 with successful allografts (including 5 mixed chimeras) and 4 with autologous recovery; whereas 7 animals died, 5 from infections during BM aplasia and 2 from acute graft-versus-host disease. By comparison, 30 of 34 dogs (88%) receiving hematopoietic growth factors in addition to the BM graft survived, 17 with successful allografts (including 10 mixed chimeras) and 13 with autologous recovery; whereas 4 died, all with infection related to BM aplasia after rejection of the allograft. Survival was similar for recipients of G-CSF, SCF, or the combination of G-CSF and SCF. Logistic regression analyses, which accounted for possible effects of TBI dose, showed a trend for improved survival in dogs receiving growth factors (P = .09), no change in allogeneic engraftment (P = .74), and a slight increase in autologous recovery (P = .22). In agreement with previous data, we found that grafts of BM from DLA-identical littermates improved survival of recipient dogs exposed to low but otherwise lethal doses of TBI. A further improvement in survival could be achieved by additional treatment with G-CSF, SCF, or G-CSF/SCF. Results suggest that treatment by hematopoietic growth factors along with BM grafts should be considered for victims of radiation accidents. 相似文献
26.
Girish M. Nair Pablo B. Nery Calum J. Redpath Buu-Khanh Lam David H. Birnie 《The Canadian journal of cardiology》2014
The purpose of this review is to understand the epidemiology, clinical features, etiopathogenesis, and management of atrioesophageal fistula (AEF) after atrial fibrillation (AF) ablation. The incidence of AEF after AF ablation is 0.015%-0.04%. The principal clinical features include fever, dysphagia, upper gastrointestinal bleeding, sepsis, and embolic strokes. The close proximity of the esophagus to the posterior left atrial wall is responsible for esophageal injury during ablation. Prophylactic proton pump inhibitors, esophageal temperature monitoring, visualization of the esophagus during catheter ablation, esophageal protection devices, and avoidance of energy delivery in close proximity to the esophagus play an important role in preventing esophageal injury. Early surgical repair or esophageal stenting are the mainstay of treatment. Eliminating esophageal injury during AF ablation is of utmost importance in preventing AEF. A high index of suspicion and early intervention is necessary to prevent fatal outcomes. 相似文献
27.
Rafael Centuriao Brinkerhoff Eduarda Santa-Helena Paulo C. do Amaral Diego da C. Cabrera Renata F. Ongaratto Patrick M. de Oliveira Caroline Da Ros Montes D'Oca Carla A. Neves Gonalves Luiz E. Maia Nery Marcelo G. Montes D'Oca 《RSC advances》2019,9(43):24688
Polyhydroquinolines (PHQs) are the unsymmetrical Hantzsch derivatives of 1,4-dihydropyridines with several biological applications. In this work, new fatty 2- and 3-substituted PHQ derivatives from different fatty acids and fatty alcohol feedstocks were synthesized at good yields via a four-component reaction (4CR). The antioxidant activities of fatty PHQs were investigated using three different antioxidant methods. The experiments showed that the compounds derived from 2-nitrobenzaldehyde and fatty palmitic (C16:0) and oleic (C18:1) chains showed better antioxidant activity. This revealed that combining the ortho NO2 group in the aromatic ring with the insertion of fatty chains in the PHQ core contributed to the antioxidant activity. However, among all the fatty PHQs tested, the fatty 2-substituted compound derived from oleyl alcohol and 2-nitrobenzaldehyde showed the highest antioxidant activity (EC50, 2.11–4.69 μM), which was similar to those of the antioxidant standards butylated hydroxytoluene (EC50, 1.98–6.47 μM) and vitamin E (EC50, 1.19–5.88 μM). In addition, this lipophilic compound showed higher antioxidant activity than the antihypertensive drug nifedipine (EC50, 49.25–126.86 μM). These results indicate that the new fatty PHQs may find novel applications as antioxidant additives.The insertion of a fatty long chain into polyhydroquinoline (PHQ) core contributes to antioxidant potential, the new fatty PHQs showed activities similar to commercial antioxidants. 相似文献
28.
Matheus Melo Pithon Iane Souza Nery Silva Indira Oliveira Almeida Marine Soares Nery Michele Luz de Souza George Barbosa Alex Ferreira dos Santos Raildo da Silva Coqueiro 《The Angle orthodontist》2014,84(2):231
Objective:To determine whether photos or silhouettes are adequate methods for evaluating the esthetic profiles of black subjects and whether black and white evaluators have different preferences for esthetic profiles.Materials and Methods:One photographic record of the profile of a black female patient with accentuated dental bimaxillary dentoalveolar protrusion was randomly selected. The image of the patient''s profile was altered to produce a series of seven photos and seven silhouettes (a total of 14 images) with different lip positions but uniform distances in relation to the esthetic plane created by Ricketts (line E). Fifty black and 50 white lay evaluators were invited to enumerate the photos and silhouettes, produced according to the lip position, in the order in which they considered most esthetically pleasing.Results:The number of preferences found to be within the esthetic norm was slightly higher among the photographs than among the silhouettes; the esthetic profile with a deviation of −2 mm from line E was elected as the most attractive, and the esthetic pattern with a deviation of +6 mm from the normal line E was considered the least attractive. There were no statistically significant differences between the preferences related to the variables race, sex, and educational background.Conclusions:The esthetic attractiveness of the facial profiles of black subjects in photos and silhouettes was evaluated in a similar manner among black and white evaluators. Among both black and white evaluators, the greatest preference was for the slightly concave profile, which was within the limit considered standard. 相似文献
29.
BACKGROUND: There is a paucity of information regarding prostate cancer (PCa) risk factors among Hispanics, the fastest-growing ethnic group in the United States. METHODS: This population-based case-control study included 176 Texas men of Mexican descent with PCa and 174 age- and ethnicity-matched controls. Demographic, lifetime occupational history, family history of cancer, lifestyle (e.g., smoking, alcohol, diet, and recreational physical activity) and anthropometric information were collected by personal interviews. Chemical exposure and physical activity were determined using job-exposure matrices for each reported job. RESULTS: Logistic regression models adjusted for relevant covariates were used to evaluate their independent effects. Compared to controls, cases were three times more likely to work in jobs with high agrichemical exposure (OR = 3.44, 95% CI 1.84-6.44), and 54% less likely to work in jobs with moderate/high occupational physical activity (OR = 0.46, 95% CI 0.28-0.77). In analyses stratified by stage, cases with organ-confined PCa were three times more likely to have high agrichemical exposure (OR = 3.39, 9%CI 1.68-6.84), and 56% less likely to have moderate/high levels of occupational physical activity (OR = 0.44, 95% CI 0.26-0.76). Increased risk of being diagnosed with advanced PCa was associated with obesity at time of diagnosis (OR = 2.50, 95% CI 1.20-5.20) and high levels of agrichemical exposure (OR = 4.65, 95% CI 1.97-10.97), but not with occupational physical activity. CONCLUSIONS: This case-control study, the first conducted in a homogeneous Hispanic population, identified modifiable PCa risk factors, such as physical activity and agrichemical exposure, which may be useful in developing interventions for this understudied population. 相似文献
30.