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51.
Estrogen receptor alpha and beta gene polymorphisms are not risk factors for recurrent miscarriage in a Brazilian population. 总被引:1,自引:0,他引:1
Aline Morandi Aléssio Lúcia Helena Siqueira Egle Cristina Couto de Carvalho Ricardo Barini Ant?nio de Pádua Mansur Nelci Fenalti Hoehr Joyce Maria Annichino-Bizzacchi 《Clinical and applied thrombosis/hemostasis》2008,14(2):180-185
The aim of this study was to determine the prevalence of alpha (ESR1: c.454-397T>C and c.454-351A>G) and beta (ESR2: 1082G>A and 1730G>A) estrogen receptor gene polymorphisms in 2 Brazilian ethnic groups (Caucasian, African Brazilian) and to investigate their association with recurrent miscarriage (RM) in 75 women with a history of 3 or more consecutive pregnancy losses and 139 controls with at least 2 live births and no history of pregnancy loss. Polymerase chain reaction and restriction fragment length polymorphism were used to identify gene polymorphisms. Coagulation methods were used to measure protein C, protein S, and fibrinogen, and a chromogenic method was used for antithrombin quantification. Significantly higher prevalences of 1082G>A and 1730G>A polymorphisms were seen in African Brazilian and Caucasian controls, respectively. There was no association between RM and ESR polymorphisms. There was a difference in the genotype prevalence in the c.454-39T>C polymorphism between RM and control Caucasians, but this finding was not associated with an increased risk of miscarriage. There was no synergistic or additive effect between ESR polymorphisms and thrombophilia in RM patients. A difference in the prevalence of ESR polymorphisms was observed, according to ethnic origin. ESR polymorphisms could not be considered a risk factor for RM. 相似文献
52.
Ismael Francisco Mota Siqueira Guarda Cristiano Jesus Correia Ana Cristina Breithaupt-Faloppa Sueli Gomes Ferreira Ana Carolina Ramos Moreno Marina Baquerizo Martinez Mauricio Rocha-e-Silva Paulina Sannomiya 《Clinics (S?o Paulo, Brazil)》2015,70(7):508-514
OBJECTIVES:Experimental studies on sepsis have demonstrated that ethyl pyruvate is endowed with antioxidant and anti-inflammatory properties. This study aimed to investigate the effects of ethyl pyruvate on leukocyte-endothelial interactions in the mesenteric microcirculation in a live Escherichia coli-induced sepsis model in rats.METHODS:Male Wistar rats were administered an intravenous suspension of E. coli bacteria or were subjected to a sham procedure. Three hours after bacterial infusion, the rats were randomized into the following groups: a control group without treatment, a group treated with lactated Ringer''s solution (4 mL/kg, i.v.), and a group treated with lactated Ringer''s solution (4 mL/kg, i.v.) plus ethyl pyruvate (50 mg/kg). At 24 h after bacterial infusion, leukocyte-endothelial interactions were investigated using intravital microscopy, and the expression of P-selectin and intercellular adhesion molecule-1 was evaluated via immunohistochemistry. White blood cell and platelet counts were also determined at baseline and 3 h and 24 h after E. coli inoculation.RESULTS:The non-treated and lactated Ringer''s solution-treated groups exhibited increases in the numbers of rolling leukocytes (∼2.5-fold increase), adherent cells (∼3.0-fold), and migrated cells (∼3.5-fold) compared with the sham group. In contrast, treatment with Ringer''s ethyl pyruvate solution reduced the numbers of rolling, adherent and migrated leukocytes to the levels observed in the sham group. Additionally, the expression of P-selectin and intercellular adhesion molecule-1 was significantly increased on mesenteric microvessels in the non-treated group compared with the sham group (p<0.001). The expression of both adhesion molecules was reduced in the other groups, with ethyl pyruvate being more effective than lactated Ringer''s solution. Infusion of bacteria caused significant leukopenia (3 h), followed by leukocytosis with granulocytosis (24 h). There was also an intense and progressive reduction in the number of platelets. However, no differences were observed after treatment with the different solutions.CONCLUSIONS:The presented data suggest that ethyl pyruvate efficiently reduces the inflammatory response in the mesenteric microcirculation in an experimental model of sepsis induced by live E. coli and is associated, at least in part, with down-regulation of P-selectin and intercellular adhesion molecule-1. 相似文献
53.
Ana Carolina R. Souza Beth Burgwyn Fuchs Henrique M. S. Pinhati Ricardo A. Siqueira Ferry Hagen Jacques F. Meis Eleftherios Mylonakis Arnaldo L. Colombo 《Antimicrobial agents and chemotherapy》2015,59(10):6581-6587
Candida parapsilosis is the main non-albicans Candida species isolated from patients in Latin America. Mutations in the ERG11 gene and overexpression of membrane transporter proteins have been linked to fluconazole resistance. The aim of this study was to evaluate the molecular mechanisms in fluconazole-resistant strains of C. parapsilosis isolated from critically ill patients. The identities of the nine collected C. parapsilosis isolates at the species level were confirmed through molecular identification with a TaqMan qPCR assay. The clonal origin of the strains was checked by microsatellite typing. The Galleria mellonella infection model was used to confirm in vitro resistance. We assessed the presence of ERG11 mutations, as well as the expression of ERG11 and two additional genes that contribute to antifungal resistance (CDR1 and MDR1), by using real-time quantitative PCR. All of the C. parapsilosis (sensu stricto) isolates tested exhibited fluconazole MICs between 8 and 16 μg/ml. The in vitro data were confirmed by the failure of fluconazole in the treatment of G. mellonella infected with fluconazole-resistant strains of C. parapsilosis. Sequencing of the ERG11 gene revealed a common mutation leading to a Y132F amino acid substitution in all of the isolates, a finding consistent with their clonal origin. After fluconazole exposure, overexpression was noted for ERG11, CDR1, and MDR1 in 9/9, 9/9, and 2/9 strains, respectively. We demonstrated that a combination of molecular mechanisms, including the presence of point mutations in the ERG11 gene, overexpression of ERG11, and genes encoding efflux pumps, are involved in fluconazole resistance in C. parapsilosis. 相似文献
54.
Fatima Dumas Cintra Renata Pimentel Leite Luciana Julio Storti Lia Azeredo Bittencourt Dalva Poyares Laura de Siqueira Castro Sergio Tufik Angelo de Paola 《Arquivos brasileiros de cardiologia》2014,103(5):368-374
Background
The mechanisms associated with the cardiovascular consequences of obstructive sleep apnea include abrupt changes in autonomic tone, which can trigger cardiac arrhythmias. The authors hypothesized that nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea.Objective
To analyze the relationship between obstructive sleep apnea and abnormal heart rhythm during sleep in a population sample.Methods
Cross-sectional study with 1,101 volunteers, who form a representative sample of the city of São Paulo. The overnight polysomnography was performed using an EMBLA® S7000 digital system during the regular sleep schedule of the individual. The electrocardiogram channel was extracted, duplicated, and then analyzed using a Holter (Cardio Smart®) system.Results
A total of 767 participants (461 men) with a mean age of 42.00 ± 0.53 years, were included in the analysis. At least one type of nocturnal cardiac rhythm disturbance (atrial/ventricular arrhythmia or beat) was observed in 62.7% of the sample. The occurrence of nocturnal cardiac arrhythmias was more frequent with increased disease severity. Rhythm disturbance was observed in 53.3% of the sample without breathing sleep disorders, whereas 92.3% of patients with severe obstructive sleep apnea showed cardiac arrhythmia. Isolated atrial and ventricular ectopy was more frequent in patients with moderate/severe obstructive sleep apnea when compared to controls (p < 0.001). After controlling for potential confounding factors, age, sex and apnea-hypopnea index were associated with nocturnal cardiac arrhythmia.Conclusion
Nocturnal cardiac arrhythmia occurs more frequently in patients with obstructive sleep apnea and the prevalence increases with disease severity. Age, sex, and the Apnea-hypopnea index were predictors of arrhythmia in this sample. 相似文献55.
Paranhos LR Benedicto EN Nunes MF Kairalla SA Siqueira DF Torres FC 《International journal of orthodontics (Milwaukee, Wis.)》2012,23(1):31-37
The aim of this study was to analyze a possible correlation of different cephalometric measurements to define facial type and to evaluate the best measurement for diagnosis. The sample consisted of 95 lateral cephalograms of caucasian patients with normal occlusion, aged between 15 years and two months and 21 years and four months, of which 54 were male and 41 female. The facial types were divided into dolichofacial, mesofacial and brachyfacial, according to the standards stated by different authors, and a relationship among them was investigated using the Kappa and Total agreement methods. The highest agreement found was between FMA and SN.GoGn; the lowest was between SN. Gn and VERT index. According to literature review and the interpretation of the results, SN.GoGn appears to be the best measurement to define facial type. 相似文献
56.
57.
Simone S.M. Paiva José F. Siqueira Isabela N. Rôças Flávia L. Carmo Deborah C.A. Leite Dennis C. Ferreira Caio T.C. Rachid Alexandre S. Rosado 《Journal of endodontics》2013,39(2):190-194
IntroductionThis in vivo study used molecular microbiology methods to evaluate the effects of passive ultrasonic irrigation (PUI) as a supplementary disinfecting step after root canal preparation.MethodsSamples were taken from 10 necrotic root canals of teeth with apical periodontitis before (S1) and after rotary nickel-titanium instrumentation using 2.5% NaOCl as the irrigant (S2) and then after PUI for NaOCl activation (S3). The parameters examined included the incidence of positive broad-range polymerase chain reaction (PCR) results for bacterial presence, the impact on bacterial diversity evaluated by PCR-denaturing gradient gel electrophoresis (DGGE), the quantitative bacterial reduction determined by real-time PCR, and the identification of persistent species by clone library analysis.ResultsAll S1 samples were positive for bacteria in all tests. Treatment procedures were significantly effective in reducing the incidence of positive results for bacteria, the number of bacterial cells (infectious bioburden), and the bacterial diversity (number of species and abundance). However, the supplementary PUI approach did not succeed in significantly enhancing disinfection beyond that achieved by chemomechanical preparation. Several bacterial species/phylotypes were identified in post-treatment samples that were positive for bacteria.ConclusionsFindings from this clinical study including a small sample size suggest that PUI can be ineffective in significantly improving disinfection of the main root canal after chemomechanical procedures. 相似文献
58.
Joyce Pinho Bezerra Ariane de Siqueira Amanda Gonçalves Pires Marcelo Rocha Marques Poliana Mendes Duarte Marta Ferreira Bastos 《Journal of periodontology》2013,84(6):839-849
Background: The aim of this study is to evaluate the effects of caffeine and/or estrogen deficiency on ligature‐induced bone loss (BL), trabecular bone area (TBA), and postextraction bone healing (BH). Methods: Rats were assigned into one of the following groups (15 each): 1) control = non‐ingestion of caffeine/sham surgery; 2) caffeine = ingestion of caffeine/sham surgery); 3) ovariectomized (OVX) = non‐ingestion of caffeine/ovariectomy; or 4) caffeine/OVX = ingestion of caffeine/ovariectomy. The rats were under caffeine administration for 65 days and/or estrogen deficiency for 51 days. On day 21 after ovariectomy, one first mandibular molar received a ligature and the contralateral tooth was not ligated. The first maxillary molars were extracted 8 days before sacrifice. BL, TBA, the positive cells for tartrate‐resistant acid phosphatase (TRAP), receptor activator of nuclear factor‐κB ligand (RANKL), and osteoprotegerin (OPG) were analyzed in the furcation area of mandibular molars. Histometric BH and gene expression of bone morphogenetic protein (BMP)‐2, BMP‐7, osteopontin, and bone sialoprotein were evaluated in alveolar sockets. Results: The caffeine group presented the greatest BL and the OVX group the highest number of TRAP‐positive (TRAP+) cells around ligated teeth (P <0.05). The control group presented higher TBA and BH than the other groups (P <0.05). All test groups presented higher RANKL/OPG+ cells than the control group around ligated/unligated teeth. The OVX and caffeine/OVX groups presented a greater number of TRAP+ cells around unligated teeth than the control group (P <0.05). There were no differences among groups for gene expression (P >0.05). Conclusions: Caffeine increased BL in ligated teeth. Caffeine and/or estrogen deficiency decreased TBA in the unligated teeth and reduced BH after tooth extraction. 相似文献
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