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Introduction

Technetium-99m–sestamibi (MIBI) is the most frequently used myocardial perfusion tracer in patients with ischemic heart disease. In patients with acute ST-elevation myocardial infarction, we previously found that the defect in myocardial MIBI uptake was the same in patients injected with MIBI before primary angioplasty and in patients injected immediately after successful treatment. Thus, reperfusion may not be followed by increased uptake of MIBI. Instead, the MIBI defect after reperfusion may reflect the area at risk (AAR) defined by MIBI injected before treatment. We intended to investigate whether myocardial imaging with MIBI administered after reperfusion reflects myocardial perfusion or rather the ischemic AAR.

Methods

In 12 pigs, left anterior descending coronary artery was totally occluded for 45 min with an angioplasty balloon. After a 2-h reperfusion, MIBI was injected intravenously, and 153Gd-microspheres were injected in left atrium. AAR and infarct size (IS) were determined by histochemical staining. MIBI and microsphere distribution were evaluated by counting the sliced left ventricle on a gamma camera. Defects were defined as uptake less than 45% of maximum uptake.

Results

The mean±S.D. defect size as a fraction of left ventricle was for MIBI 21%±5.5%, AAR 25%±6.3%, IS 13%±3.9% and microspheres defect size 7.3%±5.5%. MIBI defect size overestimated IS (P=.0005) and microspheres defect size (P=.0001), but it was not significantly different from AAR (P=.30).

Conclusion

In a porcine model of myocardial infarction after 45 min of ischemia, MIBI administered 120 min after reperfusion delineates AAR.  相似文献   
24.
Aim: Adiponectin (APN) exhibits different atheroprotective effects, and we have previously reported that APN function is modulated by its binding proteins, E-selectin ligand 1, Mac-2 binding protein, and cystatin C. In the present study, we aimed to identify a novel atheroprotective mechanism of APN via C–C motif chemokine 2 (CCL2). Methods: We conducted iMAP ® -intravascular ultrasound (IVUS) in 111 Japanese male patients with stable angina. The plaque characteristics were determined where “plaque burden” [(EEM CSA − lumen CSA)/(EEM CSA)×100 (%)] >50%, and their correlation with serum CCL2 and APN levels was analyzed. Using western blot analysis, the effects of APN on the biological effects of CCL2 were examined in their mutual binding by co-immunoprecipitation assay, the monocyte migration, and the phosphorylation of MAP kinases. Results: In a clinical study, we found that the percentage of plaque in the culprit lesion was correlated positively with serum CCL2 and negatively with serum APN levels, with significance. We identified CCL2 as a novel APN-binding serum protein using immunoprecipitation and western blot analysis. CCL2-induced phosphorylation of MAP kinases and monocyte migration was significantly attenuated by APN in vitro . Conclusion: The opposite association of APN and CCL2 on the percentage of coronary plaque might be caused by their direct interaction and competitive functions on monocyte migration.  相似文献   
25.
Unstable hemoglobin (Hb) variants are the result of sequence variants in the globin genes causing precipitation of Hb molecules in red blood cells (RBCs). Intracellular inclusions derived from the unstable Hb reduce the life-span of the red cells and may cause hemolytic anemia. Here we describe a patient with a history of hemolytic anemia and low oxygen saturation. She was found to be carrier of a novel unstable Hb variant, Hb Oslo [β42(CD1)Phe→Ile (TTT>ATT), HBB: c.127T>A] located in the heme pocket of the β-globin chain. Three-dimensional modeling suggested that isoleucine at position 42 creates weaker interactions with distal histidine and with the heme itself, which may lead to altered stability and decreased oxygen affinity. At steady state, the patient was in good clinical condition with a Hb concentration of 8.0–9.0?g/dL. During virus infections, the Hb concentration fell and on six occasions during 4 years, the patient needed a blood transfusion.  相似文献   
26.
Sequence variants located in the introns of the β-globin gene may affect the mRNA processing and cause β-thalassemia (β-thal). Sequence variants that change one of the invariant dinucleotides at the exon-intron boundaries may have fatal consequences for normal mRNA splicing. Intronic variants located far from obvious regulatory sequences can be more difficult to evaluate. There is a potential for misinterpretation of such sequence variants. Hence, thorough evaluation of patient data together with critical use of databases and in silico prediction tools are important. Here, we describe two rare sequence variants in the second intron of the β-globin gene, HBB: c.316-70C>G and HBB: c.316-125A>G (NM_000518.4), both previously reported as variants causing β-thal, and later as benign sequence variants. Due to the limited number of published cases and inconsistent interpretations, the significance of these sequence variants has been unclear. We have identified these two sequence variants in multiple individuals, alone and in a variety of combinations with other δ- and β-globin defects, and we find no influence of the sequence variants on the phenotype.  相似文献   
27.
Iron deficiency (ID) cause negative outcomes on psychomotor and behavioral development of infants and young children. Children with autistic spectrum disorders (ASD) are under risk for ID and this condition may increase the severity of psychomotor and behavioral problems, some of which already inherently exist in these children. In the present study, the frequency of ID and the association between ID and autistic symptoms, developmental level, and behavioral problems in preschool children attending a clinic for ASD (N = 31) were evaluated. No association was observed between ID and the severity of autistic symptoms, developmental level and behavioral problems. ID was detected in 32.3% (N = 10) of the children based on serum ferritin level. In this study, the negative impact of low serum ferritin in ASD has not been confirmed. On the other hand, the rate of ID was considerably high in this sample of children with ASD compared to normative data of preschool children. Further studies with larger samples are needed to clarify the relationship between ID and clinical variables associated with ASD.  相似文献   
28.

Purpose

Fruit consumption is associated with a decreased risk of CVD in cohort studies and is therefore endorsed by health authorities as part of the ‘5 or more a day’ campaigns. A glass of fruit juice is generally counted as one serving. Fruit may cause protection by affecting common risk factors of CVD.

Methods

Apples are among the most commonly consumed fruits and were chosen for a comprehensive 5 × 4 weeks dietary crossover study to assess the effects of whole apples (550 g/day), apple pomace (22 g/day), clear and cloudy apple juices (500 ml/day), or no supplement on lipoproteins and blood pressure in a group of 23 healthy volunteers.

Results

The intervention significantly affected serum total and LDL-cholesterol. Trends towards a lower serum LDL-concentration were observed after whole apple (6.7 %), pomace (7.9 %) and cloudy juice (2.2 %) intake. On the other hand, LDL-cholesterol concentrations increased by 6.9 % with clear juice compared to whole apples and pomace. There was no effect on HDL-cholesterol, TAG, weight, waist-to-hip ratio, blood pressure, inflammation (hs-CRP), composition of the gut microbiota or markers of glucose metabolism (insulin, IGF1 and IGFBP3).

Conclusions

Apples are rich in polyphenols and pectin, two potentially bioactive constituents; however, these constituents segregate differently during processing into juice products and clear juice is free of pectin and other cell wall components. We conclude that the fibre component is necessary for the cholesterol-lowering effect of apples in healthy humans and that clear apple juice may not be a suitable surrogate for the whole fruit in nutritional recommendations.
  相似文献   
29.
The Brief Multidimensional Students’ Life Satisfaction Scale (BMSLSS) was developed in response to an increasing interest in the assessment, monitoring, and promotion of positive child and youth well-being. This study further examined the psychometric support for the brief instrument by evaluating its demographic relationships, internal consistency reliability and one-year test-retest reliability, and predictive validity in a sample of 284 secondary school students in the USA who were administered the BMSLSS and criterion measures on two occasions, one year apart. Consistent with predictions, the results indicated acceptable internal consistency, moderate one-year stability coefficient, and moderate, but robust cross-sectional and longitudinal correlations with multiple indices of student engagement in their schooling. The results provide further support for the psychometric properties of the BMLSS.  相似文献   
30.
AIM: To measure the difference in lung function between newborns with univentricular hearts and healthy controls and study associations between lung function and pulmonary blood flow and pulmonary vasculature markings. METHOD: Tidal flow-volume measurements and single occlusion tests were performed before surgery on 25 unsedated spontaneously breathing newborns with univentricular hearts recruited over a 3-year period. Seventy-five healthy control infants were measured. Pulmonary blood flow was graded according to the haemodynamic effect of the echocardiographically defined anatomy of the heart defect. Pulmonary vasculature was graded according to radiological markings. RESULTS: The infants with univentricular hearts had a lower mean tidal volume of 4.7 ml (CI 2.3, 7.2, p < 0.001) (n = 24) and a lower mean compliance of the respiratory system of 12.7 ml/kPa (CI 4.6, 20.8, p = 0.004) (n = 14). Pulmonary blood flow grading was associated with respiratory rate (r = 0.53, p < 0.001), tidal volume (r =-0.48, p < 0.001), compliance (r =-0.55, p < 0.001) and resistance (r =-0.31, p = 0.043). Pulmonary vasculature grading was associated with compliance (r =-0.68, p = 0.006), resistance (r =-0.69, p = 0.007) and the time constant (r =-0.62, p = 0.042). CONCLUSION: Newborns with univentricular hearts have reduced tidal volumes and reduced compliance of the respiratory system. The lung function abnormalities are associated with the degree of pulmonary blood flow and pulmonary vasculature markings.  相似文献   
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