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Maher Saqqur MD Michael D. Hill MD MSc FRCPC Andrei V. Alexandrov MD Jayanta Roy MD Marcia Schebel BSc Andrea Krol BSc Zsolt Garami MD Ashfaq Shuaib MD FRCPC Andrew M. Demchuk MD FRCPC 《Journal of neuroimaging》2006,16(4):323-328
BACKGROUND: Stringent transcranial Doppler (TCD) criteria for diagnosing occlusion are needed for more reliable TCD performance at bedside in the acute stroke setting. SUBJECTS AND METHODS: At three academic stroke centers, we performed TCD examination for patients with symptoms of cerebral ischemia who underwent digital subtraction angiography (DSA). We used a standard insonation protocol with power M-mode Doppler (PMD) TCD (TCD 100 M, Spencer Technologies Inc., Seattle, WA). We collected mean flow velocity (MFV), pulsatility indices (PI), and power M-mode resistance signature (absent, high, or low) in symptomatic middle (MCA), anterior (ACA), posterior (PCA), and in affected (a), ipsilateral (i), and contralateral (c-lat) cerebral arteries. Ratios of aMCA/c-lat MCA, aMCA/iACA, and aMCA/iPCA MFV were subsequently calculated. PMD-TCD flow findings were evaluated with a receiver-operating characteristic (ROC) analysis for angiographically proven MCA occlusion. RESULTS: We studied 120 patients with acute cerebral ischemia with PMD-TCD examinations prior to or immediately after DSA. Lower aMCA velocities pointed to higher probability of occlusion (P= .055). The aMCA/iPCA MFV ratio was superior to the aMCA/iACA ratio and strongly predictive of occlusion at a threshold ratio of 0.5 (RR 2.31 CI(95) 2.13-2.51). High resistance or absent M-mode flow signatures in the proximal MCA were present in 87% of M1 and M2 MCA occlusions (probability 87%). In the presence of a low-resistance PMD signature, obtaining the aMCA/iPCA MFV ratio <0.5 increases probability of occlusion to 87%. Normal MFV ratios and low-resistance M-mode signatures are highly predictive of a negative angiogram for MCA occlusion. CONCLUSION: In acute cerebral ischemia, reliable criteria for proximal MCA occlusion have been developed based on combination of MFV ratios and M-mode flow resistance signatures. Validation of these criteria will require multicenter studies. 相似文献
3.
Francisco Sampaio Pedro Mateus Nuno Bettencourt Carla Costa Dias Luís Ad?o Lino Santos Madalena Teixeira Lino Sim?es Vasco Gama 《Revista portuguesa de cardiologia》2006,25(3):321-327
INTRODUCTION: Ischemic heart disease is a major cause of heart failure in western societies. However, the factors that may influence left ventricular function (LVF) recovery after an acute coronary syndrome (ACS) are still unclear. OBJECTIVE: To identify variables that may influence LVF evolution one year after ACS. METHODS: 104 patients hospitalized with ACS between 7/1/2001 and 12/31/2002 and with systolic dysfunction--defined as an echocardiographic ejection fraction (EF) < or = 45%--were randomly allocated to a planned coronary follow-up program (FUP) or a general cardiology clinic (GC); patients from both groups were also randomly referred to a structured cardiac rehabilitation program (CRP). EF was re-assessed at one year. We compared differences between patients who recovered left ventricular function (EF > 45%; group 1) and those who did not (group 2). RESULTS: One year after discharge, 44.2% of the patients had recovered function. There were no significant differences between the groups in gender (77.7 vs. 76.5% male), age (56 vs. 59 years), hypertension, diabetes, dyslipidemia, smoking habits or family history. A previous history of cardiovascular events was more frequent in group 2 (11.1% vs. 35.3%, p = 0.03). Cardiac catheterization was performed before discharge in 88.8% and 88.2% in groups 1 and 2 respectively (p = NS); no differences were found in coronary anatomy between the two groups. Angioplasty was performed in 54.2% in group 1 and 50% in group 2 (p = NS). There were no differences in the use of angiotensin-converting enzyme inhibitors (83.3% vs. 87.5%), beta-blockers (87.5% vs. 87.5%), nitrates (37.5% vs. 33.3%), aspirin (95.8% vs. 95.8%), statins (79.1% vs. 75%) or diuretics (20.8% vs. 45.8%). There was no significant difference in LVF recovery between patients randomized to FUP or GC (38.5% vs. 54.5%). 87.5% of patients who completed the CRP had normal EF at one year compared to 32.7% of patients not referred to the program (p = 0.009). Although EF improved in both groups, this improvement was greater in patients who completed a CRP (EF 8% vs. 5%, p = 0.003). CONCLUSION: A previous cardiovascular event and completion of a CRP were the only variables that influenced LVF recovery. Thus, enrollment in a CRP, in addition to standard therapy, could be an important therapeutic measure in patients with systolic dysfunction after ACS; our data suggest that these programs should be more widely used. 相似文献
4.
Recent work demonstrated that crotoxin, the main toxin of Crotalus durissus terrificus venom, inhibits macrophage spreading and phagocytic activities. The crotoxin molecule is composed of two subunits, an acidic non-toxic and non-enzymatic polypeptide named crotapotin and a weakly toxic basic phospholipase A2 (PLA2). In the present work, the active subunit responsible for the inhibitory effect of crotoxin on macrophage function was investigated. Peritoneal macrophages harvested from naive rats were used. Crotapotin (2.12, 3.75, or 8.37 nM/ml), added for 2 h to the medium of peritoneal cell incubation, did not modify the spreading and phagocytic activities of these cells. On the other hand, the PLA2 (1.43, 2.86, or 6.43 nM/ml) subunit caused a significant reduction (30, 33, and 35%, respectively) of the spreading activity. The PLA2 also inhibited the phagocytosis of opsonised zymosan, opsonised sheep erythrocytes, and Candida albicans, indicating that this inhibitory effect is not dependent on the type of receptor involved in the phagocytosis process. The inhibitory effect of PLA2 was not due to loss of cell membrane integrity, since macrophage viability was higher than 95%. These findings indicate that the inhibitory effect of crotoxin on macrophage spreading and phagocytic activities is caused by the phospholipase A2 subunit. 相似文献
5.
Benjamin Clapp Melba Jarmillo Valeria Vigil Luis Macias Marcia Bouton Cuatemoc Gallardo Andrew Kassir 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(2):242-245
BACKGROUND AND OBJECTIVES: The purpose of this study was to determine patient recall and comprehension after laparoscopic appendectomy in an underserved population. Laparoscopic surgery can lead to diagnostic uncertainty secondary to poor recall and variable port placement. METHODS: After institutional review board approval, we identified a cohort of patients who underwent laparoscopic appendectomy from 2000 to 2004 at a single institution. We then attempted to contact the patients to conduct a 10-question telephone survey, which determined whether the patient spoke English or Spanish as a primary language, ethnicity, educational level, and questions about recall of perioperative events and diagnoses. If we could not reach the patient, we tried to call back on 2 different occasions. RESULTS: Between 2000 and 2004, 186 patients underwent laparoscopic appendectomy. Of these, 65% were Hispanic. We found that only 17% of these patients returned for a postoperative visit. Only 19.3% could be contacted by phone. Forty-seven percent of the patients contacted by phone spoke Spanish exclusively. Overall 92% of patients contacted knew what operation they had, and gave their correct diagnosis. CONCLUSIONS: The low percentage of patients available to follow-up makes this study statistically insignificant. However, we believe that fact in itself is important. In Southwestern states, we see a large migrant population. This highlights the need to communicate effectively with the patients at the time of surgery, which we speculate we did based on the percentage of patients that knew their diagnosis. 相似文献
6.
Jocivania O da Silva Renata S Fernandes Fábio K Ticli Clayton Z Oliveira Maurício V Mazzi Jo?o J Franco Silvana Giuliatti Paulo S Pereira Andreimar M Soares Suely V Sampaio 《Toxicon》2007,50(2):283-291
We report here the antiproteolytic and antihemorrhagic properties of triterpenoid saponin inhibitors, named macrolobin-A and B, from Pentaclethra macroloba, against Bothrops snake venoms. The inhibitors were able to neutralize the hemorrhagic, fibrin(ogen)olytic, and proteolytic activities of class P-I and P-III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. Clotting and fibrinogenolytic activities induced by snake venoms and isolated thrombin-like enzymes were partially inhibited. Furthermore, the potential use of these inhibitors to complement antivenom therapy as an alternative treatment and/or used as molecular models for development of new therapeutical agents in the treatment of snake bite envenomations needs to be evaluated in future studies. 相似文献
7.
Anya Pimentel Gomes Fernandes Vieira Jose Maria Sampaio Meneses Jr Renato Luiz Maia 《Journal of oral pathology & medicine》2007,36(2):117-119
Cementoblastomas are benign lesions of the odontogenic ectomesenchyme that rarely occur related to the primary dentition, especially on the left side of the mandible. This study describes a case of a true cementoblastoma related to the left second primary mandibular molar in a 7-year-old child (the largest one seen in the left side of the mandible). Additionally, the radiographic and histologic findings of the lesion are described in details. 相似文献
8.
Marcia C Willing James C Torner Trudy L Burns Kathleen F Janz Teresa A Marshall Julie Gilmore John J Warren Steven M Levy 《Journal of clinical densitometry》2005,8(1):39-47
Four hundred twenty-eight white children (200 boys and 228 girls) ages 4.5-6.5 yr had spine, hip, and whole-body bone mineral density (BMD) and bone mineral content (BMC) measured by dual-energy X-ray absorptiometry(DXA) as part of the Iowa Bone Development Study. Anthropometric measurements, including height, weight, and body mass index (BMI) were determined for each child at the time the bone measurements were made. The age- and gender-specific height percentile based on the 2000 CDC Growth Charts (www.cdc.gov/growthcharts/) was determined for each child. These percentiles were used to classify children into four groups as defined by the 25th, 50th,and 75th percentile cutpoints. Percentile distributions were determined within each height quartile group to delineate percentiles (5th, 25th, 50th, 75th, 95th) for BMD and BMC. Gender differences in BMD and BMC were investigated before and after stratification into height groups. Boys had higher age-height-weight-adjusted means for most BMD and BMC measures except spine BMD. Bone measurements increased with height quartile, indicating that taller children have greater BMD and BMC compared to shorter children of the same age and gender. Within any given quartile,mean BMD and BMC measurements were similar for boys and girls, with the exception of hip BMD, for which values were consistently higher for boys (p < 0.05). In addition, whole-body BMC values were higher for boys in quartiles 1 and 3 (p < 0.05). These bone measures provide norms for young white children and serve as a reference for comparison with other racial and ethnic groups, as well as with childhood populations that are at risk for osteopenia because of chronic disease. Gender, age, and height are useful clinical predictors of BMD and BMC in young children. 相似文献
9.
Marcia Finlayson 《The American journal of occupational therapy》2004,58(1):54-63
Multiple sclerosis (MS) is a chronic, progressive neurological disease that causes demyelination of the central nervous system. Typically diagnosed in adulthood, it does not significantly reduce life expectancy. The goal of this exploratory study was to describe the health-related concerns and service needs of 27 older adults with MS, ages 55 to 81 years. Through in-depth interviews using a phenomenological approach, fear of the future was found to be a predominant concern among the participants. Within this fear, participants expressed particular concerns about experiencing further losses of mobility and independence, becoming a burden on caregivers, and having to move to a nursing home. The findings raise three major challenges for occupational therapists that include: (1) developing or modifying interventions that can enable older adults with MS to gain a sense of control over their future, (2) working with families affected by MS together with other disciplines such as psychology and social work, and (3) advocating for more and better community support options for persons with MS. 相似文献
10.
Linking the Disabilities of Arm, Shoulder, and Hand to the International Classification of Functioning, Disability, and Health. 总被引:1,自引:0,他引:1
Adriana Silva Drummond Rosana Ferreira Sampaio Marisa Cotta Mancini Renata Noce Kirkwood Tanja A Stamm 《Journal of hand therapy》2007,20(4):336-43; quiz 344
The objective of this study was to explore whether the items from a specific outcome measure, that is, Disabilities of the Arm, Shoulder, and Hand (DASH), for quantifying limb symptoms and functions in musculoskeletal disorders fit into the framework of the International Classification of Functioning, Disability and Health (ICF). All DASH items were compared to the ICF according to eight linking rules. Two groups of researchers performed the linking independently, and the results were compared by correlation. The 30 DASH items and four items from the optional modules were linked to 63 ICF categories and 11 chapters: 15 categories belong to the ICF body functions component and 48 to the activities and participation component. There were no items coded under the components body structure or environmental factors. Kappa index showed an agreement of 0.73 (p<0.001). The results showed that the content of the DASH does link well with the ICF framework. Clinicians and researchers must attend to the fact that certain domains and categories from the ICF are not covered by the DASH. Limitations of the instrument may be overcome by simultaneously using other instruments that address the intended content. 相似文献