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1.

Background

Persistent iatrogenic atrial septal defect (iASD) is a common but poorly characterized complication after cryoballoon (CB) pulmonary vein isolation (PVI) procedures. We therefore investigate its prevalence, evolution, risk factors, and clinical outcomes in a prospective longitudinal study.

Methods

A total of 108 patients (41 women, mean age 57 ± 11.3) underwent CB PVI for AF. Serial transesophageal echocardiography (TEE) was performed 9 months and then annually until 6 years after the procedure to study the characteristics of persistent iASD.

Results

Persistent iASD occurred in 33 (30.6%) patients 9 months after CB PVI. Spontaneous closure of iASD was found in 6 (22.2%) and 3 (15.8%) patients 2 and 3 years after the procedures, respectively. No spontaneous closure was observed on 4, 5, and 6-year TEE follow-up. The projected long-term persistence rate of iASD after CB PVI was therefore 20% (30.6% × 0.778 × 0.842). Using multivariate logistic regression, a higher number of cryoapplications (≥ 2 minutes) was the only independent predictor of persistent iASD 9 months after CB PVI (odds ratio [OR] 1.207; 95% confidence interval [CI], 1.033-1.411, P = 0.018). Two (1.9%) patients with significantly larger iASD size than the others (long diameter 12.6 ± 0.8 vs 3.7 ± 1.5 mm, P < 0.001; short diameter 10.9 ± 0.2 vs 3 ± 1.1 mm, P < 0.001) required percutaneous closure because of exertional dyspnea and right ventricular enlargement. Over 129.7 patient-years follow-up, during which iASD persisted, there was no occurrence of neurologic events.

Conclusions

Approximately one fifth of patients undergoing CB PVI will have permanently persistent iASD. Patients with defect sizes of greater than 10 mm may need percutaneous closure due to significant left-to-right shunting.  相似文献   
2.
Bronchodilator efficacy of metaproterenol sulfate aerosol therapy delivered either by canister or jet nebulizer was compared in 25 patients, 13 with severe asthma and 12 with COPD. Treatment was carried out in double-blind crossover fashion on 2 days and consisted of either metaproterenol sulfate solution 15 mg in 2.3 ml administered from a jet nebulizer or three puffs of metered-dose metaproterenol sulfate (total 1.95 mg) inhaled sequentially. FVC and FEV1 were monitored before and after therapy for 2 hr. In 13 asthmatic patients, FEV1 increased from a baseline mean of 0.83 L to 1.57 L at 2 hr after jet nebulizer therapy and increased from 0.84 L to 1.52 L after canister therapy. In 12 patients with COPD, FEV1 increased from 0.58 L to 0.78 L after jet nebulizer therapy and from 0.57 L to 0.76 L after canister therapy. FVC also increased similarly after each form of therapy. The two types of aerosol therapy were equally effective and were without side effects. Canister therapy has the advantage over jet nebulizer therapy by being convenient and cheaper.  相似文献   
3.
Skin tests and in vitro histamine-release reactions were used to evaluate 130 patients observed in an employee allergy clinic at a biomedical research facility. The allergens used included extracts from pollens (ragweed, grasses, trees, weeds), molds, mixed feathers, house dust, cat, dog, mouse, rat, rabbit, guinea pig, and hamster. Of all patients, 66% complained of allergic symptoms on laboratory animal exposure, although only 52% worked directly with animals. Among patients with symptoms, 91% were positive by skin test to at least one laboratory animal, and 46% had asthma. The median length of exposure to laboratory animals before onset of symptoms was 2.8 yr with 60% of the patients developing their symptoms within 3 yr. Among patients who had allergic symptoms before exposure to laboratory animals, 79% were skin test positive to laboratory animals when they were evaluated in this study. There was a close association found between the skin test and histamine-release results with the laboratory animal allergens: 91% of the 4+ skin reactors had leukocytes positive for histamine release versus 5% of the leukocyte donors with less than 1+ skin reactions. A close relationship in positive reactions to different laboratory animal allergens was also found. For example, individuals positive to mouse were positive also to rat (95%), rabbit (79%), guinea pig (83%), and hamster (88%). Patients who reacted to laboratory animals also reacted to some extent to house dust and cat and dog allergens, and about one half of the animal-allergic individuals reacted to pollens. Although nonpollen-allergic individuals can develop sensitivity to laboratory animals, the group at higher risk are allergic individuals, especially those sensitive to house dust, cats, or dogs.  相似文献   
4.
Many drugs differing widely in chemical structure uncouple mitochondrial oxidative phosphorylation in vitro. This observation has led to the hypothesis that in vivo uncoupling is the basis of their pharmacological activity. Serpasil, a parenteral preparation of reserpine, recently has been shown to uncouple oxidative phosphorylation in vervet monkey kidney mitochondria. Although the drug exhibits some properties of a "classical" uncoupler, our studies show that it has a dual effect on energy conservation. Reserpine released respiratory control in rat liver mitochondria only when dissolved in organic solvents (as in Serpasil) or when deprotonated. Reserpine also released the oligomycin-induced respiratory control in beef heart submitochondrial particles, and inhibited energized uptake of Ca2- by rat liver mitochondria. Reserpine had a dual effect on mitochondrial ATPase: It (a) enhanced ATP hydrolysis by intact liver mitochondria, and (b) inhibited ATP hydrolysis by submitochondrial particles of beef heart. On a molar basis, reserpine was less effective than carbonyl cyanide 3-chlorophenylhydrazone in all bioenergetic reactions examined. Homogenates and mitochondria isolated from brain and liver of rats stuporous from intraperitoneally injections of Serpasil exhibited no detectable abnormalities in respiratory states and responded to known uncouplers in the expected manner. There was no evidence of in vivo uncoupling of oxidative phosphorylation as a basis of the pharmacological activity of reserpine, although interference with energy transfer may be involved in toxic manifestations of the drug. The results indicate the need for caution in interpreting the action of drugs formulated in complex pharmaceutical preparations and based solely on in vitro experiments.  相似文献   
5.
Epidemiological studies have indicated that the risk of atherothrombotic coronary artery disease (CAD) is higher in patients with diabetes, but these results have not been consistently observed across clinical trials. To address this apparent discrepancy, we can apply the results of genome-wide association studies (GWAS) to provide a better understanding of the shared genetic architecture of diabetes and atherothrombotic CAD. For instance, a large GWAS has identified 16 novel loci that are associated with both diabetes and atherothrombotic CAD. These genetic variants may also be used to assess potential causal relationships reported in observational studies and clinical trials through Mendelian randomization analyses. For example, several Mendelian randomization analyses have shown that diabetes is associated with CAD independent of other risk factors (odds ratio [OR]: 1.63, 95% confidence interval [CI]: 1.23–2.07; P = 0.002). Furthermore, Mendelian randomization analyses can provide more insight into the perceived risk of diabetes among patients without diabetes receiving statin therapy. Here, genetically lower activity of HMG-CoA reductase (HMGCR) was associated with a modest increase in diabetes (OR per allele: 1.02, 95% CI: 1.00–1.05). These results highlight the biological mechanisms that link diabetes with the use of statins. In addition, this work illustrates the great potential value of genetic studies to clarify the mechanistic relationships among atherosclerotic vascular disease, dysglycemia, and diabetes. More research is needed to delineate and subsequently better understand the genetic links between diabetes and atherosclerosis.  相似文献   
6.
Prediabetes     
The burden of diabetes is expected to rise from 415 million individuals in 2015 to 642 million individuals by 2040. Most individuals pass through a phase of prediabetes before developing full-blown diabetes. Insulin resistance, impaired incretin action, and insulin hypersecretion are central to the pathophysiology of prediabetes. Individuals older than 40 years of age and other high-risk individuals should be screened for diabetes with fasting plasma glucose and/or hemoglobin A1c. For those diagnosed with prediabetes, the goal of treatment should be restoring euglycemia, because there are data showing that restoring normoglycemia during prediabetes and early diabetes can produce lasting remission. The preferred approach for this is intensive lifestyle intervention, which besides reducing progression to diabetes, has also been shown to reduce all-cause mortality in a long-term follow-up study. The best evidence for a pharmacological approach is with metformin. Other drugs that have shown efficacy include thiazolidinediones, alpha-glucosidase inhibitors, orlistat, basal insulin, and valsartan. However, except for metformin, none of these drugs are currently recommended for this purpose. Newer agents such as glucagon-like peptide-1 agonists and dipeptidyl peptidase 4 (DPP-4) inhibitors also have considerable promise in this area. Bariatric surgery can be offered to patients with metabolic syndrome and body mass index of 30-35.  相似文献   
7.
8.
Purpose: Tubercular lymphadenitis (TBLA) is a common manifestations of extrapulmonary tuberculosis (EPTB) accounting for 30-40% of cases. Prompt diagnosis and timely initiation of anti-tubercular therapy (ATT) is the key for successful clinical outcome. This study was carried out to evaluate multiplex polymerase chain reaction (MPCR) using MPB64 and IS6110, and compare with the conventional methods for rapid diagnosis of TBLA. Materials and Methods: In our study, lymph node fine-needle aspirates of patients were evaluated for TBLA. They were classified as Group I: TBLA group, divided into (a) Confirmed TBLA cases (n = 80): Culture/smear-positive or cytological examination showing presence of epithelioid cell granuloma with or without multinucleate giant cell and caseation necrosis with presence of AFB, and (b) suspected TBLA cases (n = 30): Culture/smear-negative and cytological examination showing presence of epithelioid cell granuloma and response to ATT and Group II (Control) (n = 25): Patients of lymphadenopathy confirmed to be caused by other diseases such as sarcoidosis, lymphoma, etc., All samples were subjected to conventional tests and MPCR. For MPCR we used Mycobacterium tuberculosis-specific deoxyribonucleic acid sequences specific for the MPB64 and IS6110 region. Results: In the confirmed TBLA group, Ziehl–Neelsen (ZN) smear, cytology, culture, and MPCR positivity was 30%, 70%, 26.3%, and 91.3% respectively. In the suspected TBLA group, smear and culture were negative, and sensitivity of cytology and MPCR was 73.3% and 86.6%, respectively. In the control group all tests were found to be negative, thus giving a specificity of 100% to all the tests in the study. Conclusion: In conclusion, techniques like MPCR with high sensitivity and specificity can play an important role in rapid diagnosis of TBLA.  相似文献   
9.
Platelet-rich fibrin (PRF) is gaining acceptance as a bioactive surgical additive in regenerative dentistry. However, PRF has only been available in gel or membrane form and is not suitable for injection. Recently, however, a liquid, injectable PRF has been introduced. This paper introduces the concept of injectable PRF and discusses its applications for biologic activation of bone grafts.  相似文献   
10.
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