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71.

OBJECTIVE:

Ischemic stroke may result from transient or permanent reductions of regional cerebral blood flow. Polymorphonuclear neutrophils have been described as the earliest inflammatory cells to arrive in ischemic tissue. CXCR1/2 receptors are involved in the recruitment of these cells. However, the contribution of these chemokine receptors during transient brain ischemia in mice remains poorly understood. In this work, we investigated the effects of reparixin, an allosteric antagonist of CXCR1/2 receptors, in a model of middle cerebral artery occlusion and reperfusion in mice.

METHODS:

C57BL/6J male mice treated with reparixin or vehicle were subjected to a middle cerebral artery occlusion procedure 1 h after the treatment. Ninety minutes after ischemia induction, the monofilament that prevented blood flow was removed. Twenty-four hours after the reperfusion procedure, behavioral changes, including motor signs, were analyzed with the SmithKline/Harwell/Imperial College/Royal Hospital/Phenotype Assessment (SHIRPA) battery. The animals were sacrificed, and brain tissue was removed for histological and biochemical analyses. Histological sections were stained with hematoxylin and eosin, neutrophil infiltration was estimated by myeloperoxidase activity and the inflammatory cytokine IL-1β was measured by ELISA.

RESULTS:

Pre-treatment with reparixin reduced the motor deficits observed in this model of ischemia and reperfusion. Myeloperoxidase activity and IL-1β were reduced in the reparixin-treated group. Histological analysis revealed that ischemic injury was also attenuated by reparixin pre-treatment.

CONCLUSIONS:

Our results suggest that the blockade of the CXCR1/2 receptors by reparixin promotes neuroprotective effects by reducing the levels of polymorphonuclear infiltration in the brain and the tissue damage associated with middle cerebral artery occlusion and reperfusion.  相似文献   
72.

OBJECTIVES:

To correlate the importance of the ankle-brachial index in terms of cardiovascular morbimortality and the extent of coronary arterial disease amongst elderly patients without clinical manifestations of lower limb peripheral arterial disease.

METHODS:

We analyzed prospective data from 100 patients over 65 years of age with coronary arterial disease, as confirmed by coronary angiography, and with over 70% stenosis of at least one sub-epicardial coronary artery. We measured the ankle-brachial index immediately after coronary angiography, and a value of <0.9 was used to diagnose peripheral arterial disease.

RESULTS:

The patients'' average age was 77.4 years. The most prevalent risk factor was hypertension (96%), and the median late follow-up appointment was 28.9 months. The ankle-brachial index was <0.9 in 47% of the patients, and a low index was more prevalent in patients with multiarterial coronary disease compared to patients with uniarterial disease in the same group. Using a bivariate analysis, only an ankle-brachial index of <0.9 was a strong predictive factor for cardiovascular events, thereby increasing all-cause deaths and fatal and non-fatal acute myocardial infarctions two- to three-fold.

CONCLUSION:

In elderly patients with documented coronary disease, a low ankle-brachial index (<0.9) was associated with the severity and extent of coronary arterial disease, and in late follow-up appointments, a low index was correlated with an increase in the occurrence of major cardiovascular events.  相似文献   
73.
74.
Coronary artery anomalies (CAAs) are a rare entity but their true incidence in the general population has yet to be determined. Most CAAs are asymptomatic, but they are nevertheless the second leading cause of sudden death in apparently healthy young athletes. The new imaging methods available to cardiologists, including CT angiography and MRI, now enable noninvasive diagnosis and characterization of these anomalies. The authors review the literature and present a retrospective study of 360 consecutive patients who underwent cardiac CT angiography. Demographic, clinical and angiographic characteristics were studied. The incidence of CAAs in this population was 2.69%. In order to better characterize this disorder, including diagnostic strategy, screening, treatment and prognosis, the authors suggest the establishment of a national registry of cardiac CT angiography. Such a registry would fill the existing gap in information on exams performed in the country, enriching current knowledge about this disease and noninvasive cardiac imaging in Portugal.  相似文献   
75.
BACKGROUND: The increased prevalence of overweight and obesity has reached alarming proportions worldwide and has serious health implications, including an association with an increase in metabolic syndrome. Among the methods to control metabolic syndrome, bariatric surgery plays an important role and can provide a significant improvement in the components of metabolic syndrome. Objective: The aim of this study was to determine the relationship between the preoperative body mass index (BMI) and the postoperative resolution of metabolic syndrome [using the National Cholesterol Education Program (NCEP ATP III criteria)] in patients undergoing Roux-en-Y gastric bypass (RYGB). Methods: Retrospective analysis of a consecutive series of cases, stratified by BMI into three groups (group 1, BMI <40 kg/m(2), group 2, BMI 40-49.9 kg/m(2), and group 3, BMI 50 ≥ kg/m(2)) consisting of both sexes between 20 and 60 years of age. The cohort consisted of 149 patients undergoing RYGB. Anthropometric, biochemical, and clinical evaluations were performed preoperatively and then at 30 and 180 days postoperatively. Results: The average age was 40 years, and the patients were predominately female (72%). At the end of the study period, all groups showed a significant reduction in metabolic syndrome compared with preoperative levels. Logistic regression showed a higher percentage of metabolic syndrome in patients in group 3 after 180 days. Conclusion: There was significant resolution of metabolic syndrome in all groups, independently of the preoperative BMI. However, in group 3 (BMI ≥ 50 kg/m(2)), 22% of individuals still presented with metabolic syndrome at 180 days postoperatively (P=0.03).  相似文献   
76.
ObjectiveTo assess the association of the polymorphisms of the interleukin-18 (IL-18) gene with rheumatoid arthritis (RA) and with risk factors for cardiovascular diseases (CVD).MethodsThis sample comprised 97 patients with RA and 151 healthy controls. In the patients, risk factors for CVD were analyzed, such as cholesterol levels, arterial hypertension, smoking habit, C-reactive protein (CRP) level, and rheumatoid factor. DNA was extracted and the single nucleotide polymorphisms (SNP) at the ?607C/A and ?137G/C positions of the IL-18 gene were assessed in both groups. The Hardy-Weinberg equilibrium (HWE) was calculated and the odds ratio (OR) test performed, considering a 95% CI and P < 0.05.ResultsThe frequencies of the ?607A allele in patients with RA and in controls were 0,443 and 0.424, respectively, and of the ?137C allele, 0.304 and 0.291, respectively. The genotype frequencies were in HWE, except for controls in the ?137 locus (P = 0.006). Association of the polymorphisms of the IL-18 gene was found with neither RA nor risk factors for CVD, including cholesterol level and CRP (P > 0.05). In addition, more smokers were found among patients with RA as compared with controls (OR = 1.691; P = 0.088), and the CRP levels were slightly higher in patients who smoked than in patients who did not (OR = 2.673; P = 0.061).ConclusionsIn this sample of patients with RA in the South of Brazil, association of the polymorphisms of the IL-18 gene was observed with neither RA nor risk factors for CVD.  相似文献   
77.
78.

Background

Solitary fibrous tumors of the orbit are uncommon lesions, only one relatively large series having been published. Neoplasms, formerly considered as separate entities, including hemangiopericytoma, are presently encompassed as solitary fibrous tumors, a unifying designation. There is a tendency towards recurrence and some cases are malignant. Their rarity justifies the publication of new cases, in order to increase the amount of information about this pathological entity.

Case report

A 40-year-old female patient developed swelling in the left lower lid and after slow progression of the symptom during 2 years, presented herself to our elective surgery service. Image exams showed a 20-mm encapsulated tumor. Surgical treatment was performed: complete excision, made difficult by the growth of the lesion amid the inferior rectus and inferior oblique muscles. Histopathological and immunochemical examinations with CD34 positivity, diagnosed a solitary fibrous tumor, without suggestive signs of malignancy. After a follow-up of 40 months, no recurrence has been detected.

Discussion

Solitary fibrous tumors, though uncommon, should be considered in the differential diagnosis of orbital expansive lesions. The key point to diagnosis is finding CD34 positivity in immunohistochemical examination. Such tumors have a tendency for recurrence, even after more than 5 years.  相似文献   
79.

Objectives

This study evaluated the influence of different exposure times to saliva in situ in comparison with an antioxidant treatment on composite resin bond strength to human enamel restored after tooth bleaching.

Material and Methods

Forty human teeth specimens measuring 5x5 mm were prepared and randomly allocated into 5 groups with 8 specimens each: Gct (control group, restored on unbleached enamel); Gbl (restored immediately after bleaching); Gsa (bleached, treated with 10% sodium ascorbate gel for 60 min and restored); G7d (bleached, exposed to saliva in situ for 7 days and restored); and G14d (bleached, exposed to saliva in situ for 14 days and restored). Restored samples were cut into 0.8 mm2 sticks that were tested in microtensile. Specimens were microscopically analyzed and failure modes were classified as adhesive, cohesive, or mixed. Pretest and cohesive failures were not considered in the statistical analysis, which was performed with one-way ANOVA and Tukey''s post-hoc test (α=0.05), with the dental specimen considered as the experimental unit.

Results

Mean bond strength results found for Gbl in comparison with Gct indicated that bleaching significantly reduced enamel adhesiveness (P<0.01). However, no statistically significant differences were found between Gct, Gsa and G7d (P>0.05). Bond strength found for G14d was significantly higher than for Gsa (P<0.01). Fractures modes were predominantly of a mixed type.

Conclusions

Bonding strength to bleached enamel was immediately restored with the application of sodium ascorbate and exposure to human saliva in situ for at least 7 days. Best results were obtained with exposure to human saliva in situ for 14 days. Treatment with sodium ascorbate gel for 60 min may be recommended in cases patients cannot wait for at least 7 days for adhesive techniques to be performed.  相似文献   
80.
Abstract

According to the author's narrative model of change, clients may maintain a problematic self-stability across therapy, leading to therapeutic failure, by a mutual in-feeding process, which involves a cyclical movement between two opposing parts of the self. During innovative moments (IMs) in the therapy dialogue, clients’ dominant self-narrative is interrupted by exceptions to that self-narrative, but subsequently the dominant self-narrative returns. The authors identified return-to-the-problem markers (RPMs), which are empirical indicators of the mutual in-feeding process, in passages containing IMs in 10 cases of narrative therapy (five good-outcome cases and five poor-outcome cases) with females who were victims of intimate violence. The poor-outcome group had a significantly higher percentage of IMs with RPMs than the good-outcome group. The results suggest that therapeutic failures may reflect a systematic return to a dominant self-narrative after the emergence of novelties (IMs).  相似文献   
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