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171.
Tolentino ES Centurion BS Tjioe KC Casaroto AR Tobouti PL Frederigue Junior U Lara VS Damante JH Sant'ana E Gonçales ES 《Oral surgery, oral medicine, oral pathology and oral radiology》2012,113(6):e40-e45
Juvenile ossifying fibroma (JOF) is a rare fibro-osseous neoplasm, defined as a variant of the ossifying fibroma that arises within the craniofacial bones. Two subgroups, juvenile psammomatoid ossifying fibroma (PsJOF) and juvenile trabecular ossifying fibroma, have been delineated by their histology. PsJOF occurs predominantly in the sinonasal and orbital bones. This work reports on 2 cases of extensive PsJOF in the body of the right mandible as well as reviews the literature regarding the radiographic and histologic features, treatment, and prognosis of PsJOF of the jaws. 相似文献
172.
Paulo Sérgio Gon?alves da Costa Geyza Machado Ribeiro Cleber Soares Junior Lenilton da Costa Campos 《The American journal of tropical medicine and hygiene》2012,87(4):741-742
Dengue fever has been a major problem in hospital settings in Brazil for the past 15 years. The main concern has been the severe forms, i.e., dengue hemorrhagic fever and dengue shock syndrome. Hemorrhagic events of different degrees have also been a major concern. We report five cases of large vein thrombotic events associated with the acute phase of dengue fever, including a previously non-reported case of mesenteric vein thrombosis. Complications such as these could have been overlooked in the diagnosis of dengue fever, given that the major concern is the hemorrhagic event.Dengue fever frequently affects Brazil, where thousands of cases have been diagnosed annually and all four dengue virus serotypes (DENV-1 through DENV-4) have been reported, sometimes concurrently in the same region.1,2 Hemorrhagic events of different degrees have often been described in dengue, but thrombotic events have not been extensively reported, despite the wide range of increased procoagulant activity during illness.1,3–8 During a recent outbreak, several cases of thrombotic events affected large veins in dengue fever patients. We report cases of unusual and overlooked complication of dengue fever.From January 2011 through March 2011 during a local outbreak of dengue fever caused by DENV-1 and DENV-2 according to local health officials, five patients were given diagnoses by imaging techniques (pulmonary computed tomography angiography, cholangio-magnetic resonance imaging, and Doppler ultrasound of lower extremities) as having large vessel thrombosis. These patients were part of 92 serologically confirmed (by immunochromatographic strip test or IgM antigen-capture enzyme-linked immunosorbent assay) patients with dengue (60% women and 40% men, median age = 39 years, age range = 10–99 years) admitted to Monte Sinai Hospital (200 beds) in Juiz de Fora, (population = 500,000), Minas Gerais, Brazil. This study was approved by the Ethical Committee of Monte Sinai Hospital.Twenty-three patients (25%) were classified as having dengue shock syndrome or dengue hemorrhagic fever and 4 deaths were recorded (case-fatality rate = 4.3%). These thrombotic patients represented 5.4% of all dengue inpatients. All thrombotic events were identified within the first five days of illness, and all patients had symptoms compatible with the reported thrombotic event at hospital admission. No thrombotic events were identified among the remaining patients during hospitalization, and none of the patients them received drugs for thrombosis prophylaxis, which is contraindicated in dengue.The demographic and clinical characteristics of the five patients are summarized in Figure 1), which was associated with jaundice and severe sepsis by Escherichia coli demonstrated by blood culture. Known risk factors for thrombotic events such as smoking, use of oral contraceptives, and being overweight were absent in all patients and none had had any similar diagnosis or symptoms.Open in a separate windowFigure 1.T1-weighted cholangio-magnetic resonance image with contrast of dengue patient 5 showing the superior mesenteric vein (SMV) with a large thrombus (arrow) occupying the vein lumen. SMA = superior mesenteric artery; IVC = inferior vena cava; Ao = aorta.
Open in a separate window*US = ultrasound; DVT = deep vein thrombosis; CTA = computed tomography angiography; PTE = pulmonary thromboembolism; C-MRI = cholangio-magnetic resonance imaging; SIRS = systemic inflammatory response syndrome; MVT = mesenteric vein thrombosis.†Reference value = 140–400 × 109 /L (sample obtained on hospital day 1).‡Reference values: males = 41–53%; females = 36–46% (sample obtained on hospital day 1).§Reference value < 10 IgMPL/IgGPL (IgM phospholipid units, 1 IgMPL unit = 1 μg of IgM); IgGPL (IgG phospholipid units, 1 GPL unit = 1 μg of IgG).Increased levels of IgM against phospholipids were detected in four patients, but levels of IgG against phospholipids above the reference level were detected in only one patient (by enzyme immunoassay), and this was the only positive result in thrombophilia screening. Although most of the patients were dehydrated, severe hemoconcentration was not observed. Leukocyte counts were within the reference range and levels of D-dimer were increased in all patients. The international normalized ratio (prothrombin time) was normal or slightly prolonged in all patients and none had hemorrhagic events. None of the thrombotic patients were classified as having dengue shock syndrome or dengue hemorrhagic fever. All patients were treated with low molecular weight heparin and recovered. Although not completely understood, low platelet counts and function, increased vascular permeability, increased thrombomodulin, increased tissue plasminogen activator, and antibody cross-reactivity with endothelial cells and with specific coagulation proteins are among the suggested mechanisms responsible for hemorrhagic phenomena in dengue fever.3–8Myriad factors, including cytokines, fibrinolysis, and the complement system, might increase thrombotic risk in dengue fever patients.3–5 Increased PAI-1 plasma levels seem to be common in DENV infection and have been associated with greater risk for thrombosis.7 Disseminated intravascular coagulation and consequent microthombi formation have also been reported in dengue fever but have not been associated with large vessel thrombosis.5 Low concentrations of plasma anticoagulant proteins C and S and antithrombin III have also been detected in severe dengue but have not been associated with clinical thrombosis.4Increased levels of IgM against phospholipids were detected in all but one patient in this series, but these levels are of low clinical significance for thrombosis. Thus, except for increased levels of IgG against phospholipids in one patient, no other procoagulant risk factor was identified in this case series.9 Antibodies against phospholipids and increased lupus anticoagulant have been anecdotally associated with thrombotic events in peripheral arteries and cerebral vasculature in dengue fever patients.10,11 Venous cerebral vasculature thrombosis and ischemic stroke not associated with antibodies against phospholipids or other risk factors have been rarely reported in dengue fever patients.12Severe dehydration, a well known condition associated with thrombotic events, was not detected in any patient. All but one of the patients was > 50 years of age. Thus, the role of older age in thrombotic events in dengue fever should be considered. It is noteworthy that none of the thrombosis cases occurred in patients with dengue shock syndrome or dengue hemorrhagic fever, but the small number of patients with these conditions is not a reasonable explanation.The involved mechanism seems to be related to events that occurred during the early phase of the disease because the thrombotic events were clinically detected at admission and no episode of thrombosis was detected among the remaining dengue fever patients throughout hospitalization or during outpatient follow-up. Loss of endothelium non-thrombogenic protective factors has been identified in severe dengue early in the course of the disease.1To our knowledge, deep vein thrombosis, pulmonary thromboembolism, and mesenteric vein thrombosis have not been reported in direct association with dengue fever.1,11,12 Mesenteric vein thrombosis was an unusual complication of DENV infection, and was erroneously diagnosed in an imaging study of suspected cholangitis in a patient with clinical sepsis without a primary source. Awareness for these kinds of complications should be recommended to all practitioners who treat patients with dengue fever, particularly in hospital settings. 相似文献
Table 1
Demographic, clinical, and laboratory characteristics of five dengue fever patients with thrombotic events, Brazil*Patient/age (years)/sex | Platelets (× 109/L)† | Hematocrit, %‡ | Antibodies against phospholipid§ | Imaging | Manifestations | Thrombotic event | Illness day of thrombosis diagnosis |
---|---|---|---|---|---|---|---|
1/89/F | 113 | 33 | IgG 4.5, IgM 17.6 | Doppler US | Leg pain and edema | DVT | 2 |
2/41/F | 112 | 32.9 | IgG 7.9, IgM 1.9 | Doppler US | Leg pain and edema | DVT | 3 |
3/89/F | 52 | 45 | IgG 32.8, IgM 14.2 | CTA | Dyspnea | PTE | 1 |
4/51/F | 45 | 41 | IgG 0.6, IgM 12.0 | CTA | Dyspnea | PTE | 2 |
5/61/M | 37 | 42 | IgG 6.1, IgM 11.3 | C-MRI | SIRS | MVT | 5 |
173.
174.
Adriana Sampaio Sylvain Bouix Nuno Sousa Cristiana Vasconcelos Montse Férnandez Martha E. Shenton Óscar F. Gonçalves 《Brain structure & function》2013,218(3):711-720
Brain abnormalities in Williams syndrome (WS) have been consistently reported, despite few studies have devoted attention to connectivity between different brain regions in WS. In this study, we evaluated corpus callosum (CC) morphometry: bending angle, length, thickness and curvature of CC using a new shape analysis method in a group of 17 individuals with WS matched with a typically developing group. We used this multimethod approach because we hypothesized that neurodevelopmental abnormalities might result in both volume changes and structure deformation. Overall, we found reduced absolute CC cross-sectional area and volume in WS (mean CC and subsections). In parallel, we observed group differences regarding CC shape and thickness. Specifically, CC of WS is morphologically different, characterized by a larger bending angle and being more curved in the posterior part. Moreover, although CC in WS is shorter, a larger relative thickness of CC was found in all callosal sections. Finally, groups differed regarding the association between CC measures, age, white matter volume and cognitive performance. In conclusions, abnormal patterns of CC morphology and shape may be implicated in WS cognitive and behavioural phenotype. 相似文献
175.
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
176.
D. E. Sakas J. K. Krauss J. Schramm M. Scerrati H. J. Reulen M. Cunha E Sá J. van Loon B. Nuttin Α. Gonçalves-Ferreira J. Regis D. Van Roost 《Acta neurochirurgica》2013,155(9):1725-1729
The present Training Charter in Epilepsy Surgery Added Competence constitutes the third stage of a program initiated by the European Society for Stereotactic and Functional Neurosurgery (ESSFN) and substantiated in close collaboration with the Union Européennedes Médecins Spécialists (UEMS) and the European Association of Neurosurgical Societies (EANS). This program aims to raise the standards of clinical practice by guiding education and quality control concepts. The particular sections of this Charter include: definitions and standards of added competence training, relations of the Epilepsy Unit with the Neurosurgical Department, duration of epilepsy surgery fellowship, institution and training program director requirements, operative totals for epilepsy surgery, educational program, individual requirements, and evaluation and qualification of the trainees. The specification of all these requirements is expected to improve harmonisation and quality of epilepsy surgery practice across Europe, and enhance the clinical activity and the scientific productivity of existing neurosurgical centres. 相似文献
177.
Melanie Boerries Florian Grahammer Sven Eiselein Moritz Buck Charlotte Meyer Markus Goedel Wibke Bechtel Stefan Zschiedrich Dietmar Pfeifer Denis Laloë Christelle Arrondel Sara Gonçalves Marcus Krüger Scott J. Harvey Hauke Busch Joern Dengjel Tobias B. Huber 《Kidney international》2013,83(6):1052-1064
178.
Dong Bin Kim Hyuk Choi Sang Min Joo Han Ki Kim Jae Hee Shin Min Ho Hwang Jaesoon Choi Dong‐Gon Kim Kwang Ho Lee Chun Hak Lim Sun Kook Yoo Heung‐Man Lee Kyung Sun 《Artificial organs》2013,37(4):368-379
This study seeks to improve the mechanical performance of stents by conducting reliability performance testing and finite element method (FEM)‐based simulations for coronary stents. Three commercially available stent designs and our own new design were tested to measure the factors affecting performance, specifically foreshortening, recoil, radial force, and flexibility. The stents used in the present experiments were 3 mm in working diameter and 18 mm of working length. The results of the experiments indicate that the foreshortening of stents A, B, C, and our new design, D, was equivalent to 2.25, 0.67, 0.46, and 0.41%, respectively. The recoil of stents A, B, C, and D was 6.00, 4.35, 3.50, and 4.36%, respectively. Parallel plate radial force measurements were A, 3.72 ± 0.28 N; B, 3.81 ± 0.32 N; C, 4.35 ± 0.18 N; and D, 4.02 ± 0.24 N. Radial forces determined by applying uniform pressure in the circumferential direction were A, 28.749 ± 0.81 N; B, 32.231 ± 1.80 N; C, 34.522 ± 3.06 N; and D, 42.183 ± 2.84 N. The maximum force of crimped stent at 2.2‐mm deflection was 1.01 ± 0.08 N, 0.82 ± 0.08 N, 0.92 ± 0.12 N, and 0.68 ± 0.07 N for each of stents A, B, C and D. The results of this study enabled us to identify several factors to enhance the performance of stents. In comparing these stents, we found that our design, stent D, which was designed by a collaborative team from seven universities, performed better than the commercial stents across all parameter of foreshortening, recoil, radial force, and flexibility. 相似文献
179.
180.
Teixeira R Monteiro P Marques G Pego JM Louren?o M Tavares C Reboredo A Monteiro S Gon?alves F Ferreira MJ Freitas M Ribeiro G Providência LA 《Revista portuguesa de cardiologia》2012,31(9):545-554
IntroductionInhibition of platelet aggregation appears two hours after the first dose of clopidogrel, becomes significant after the second dose, and progresses to a steady-state value of 55% by day seven. Low response to clopidogrel has been associated with increased risk of stent thrombosis and ischemic events, particularly in the context of stable heart disease treated by percutaneous coronary intervention.ObjectiveTo stratify medium-term prognosis of an acute coronary syndrome (ACS) population by platelet aggregation.MethodsWe performed a prospective longitudinal study of 70 patients admitted for an ACS between May and August 2009. Platelet function was assessed by ADP-induced platelet aggregation using a commercially available kit (Multiplate® analyzer) at discharge. The primary endpoint was a combined outcome of mortality, non-fatal myocardial infarction, or unstable angina, with a median follow-up of 136.0 (79.0–188.0) days.ResultsThe median value of platelet aggregation was 16.0 U (11.0–22.5 U) with a maximum of 41.0 U and a minimum of 4.0 U (normal value according to the manufacturer: 53–122 U). After ROC curve analysis with respect to the combined endpoint (AUC 0.72), we concluded that a value of 18.5 U conferred a sensitivity of 75.0% and a specificity of 68% to that result. We therefore created two groups based on that level: group A – platelet aggregation <18.5 U, n = 44; and group B – platelet aggregation ≥18.5 U, n = 26. The groups were similar with respect to demographic data (age 60.5 [49.0–65.0] vs. 62.0 [49.0–65.0] years, p = 0.21), previous cardiovascular history, and admission diagnosis. There were no associations between left ventricular ejection fraction, GRACE risk score, or length of hospital stay and platelet aggregation. The groups were also similar with respect to antiplatelet, anticoagulant, proton pump inhibitor (63.6 vs. 46.2%, p = 0.15) and statin therapy. The variability in platelets and hemoglobin was also similar between groups. Combined event-free survival was higher in group A (96.0 vs. 76.7%, log-rank p < 0.01). Platelet aggregation higher than 18.5 U was an independent predictor of the combined event (HR 6.75, 95% CI 1.38–32.90, p = 0.02).ConclusionIn our ACS population platelet aggregation at discharge was a predictor of medium-term prognosis. 相似文献