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11.
Modified Pulmonary Vein Isolation in AF Ablation. Introduction: Pulmonary vein isolation (PVI) is the primary ablation therapy in patients with atrial fibrillation (AF). We hypothesized that high dominant frequency (DF) sites (AF nests during sinus rhythm [SR]) adjacent to the PV ostia are associated with the atrial substrate that maintains AF, and PVI incorporating the high‐frequency AF nests may have a higher efficacy. Methods and Results: In a prospective and randomized comparison, 126 symptomatic paroxysmal AF patients that underwent PVI were enrolled. We compared the efficacy of a modified PVI (ablation line: 1.0–1.5 cm from the PV ostium with encircling the AF nests [spectral analysis with DF >70 Hz during SR, Group II]) versus the anatomy‐guided conventional PVI (Group I). In Group II, the DF value along the PV ostium was lower than 70 Hz after the PVI. The primary endpoint was the freedom from symptomatic atrial arrhythmias after a single procedure. We also followed the autonomic function by a time‐domain analysis of the heart rate variability. In both groups, AF nests were observed and electric isolation was successfully obtained in all patients. With a mean duration of 16 ± 6.1 months of follow‐up, Group II had a higher single procedure efficacy without drugs (78.7% vs 66.1%, log‐rank test: P = 0.02), and fewer repeat procedures (6.6% vs 23%; P = 0.04), as compared to Group I. Conclusion: PVI incorporating the high frequency AF nests adjacent to the PV ostia had a better single procedure efficacy. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1155–1162, November 2012)  相似文献   
12.

Background:

The incidence of obesity in children is increasing worldwide, primarily in urbanized, high-income countries, and hypertension development is a detrimental effect of this phenomenon.

Objective:

In this cross-sectional study, we evaluated the prevalence of excess weight and its association with high blood pressure (BP) in schoolchildren.

Methods:

Here 4,609 male and female children, aged 6 to 11 years, from 24 public and private schools in Maringa, Brazil, were evaluated. Nutritional status was assessed by body mass index (BMI) according to cutoff points adjusted for sex and age. Blood pressure (BP) levels above 90th percentile for gender, age and height percentile were considered elevated.

Results:

The prevalence of excess weight among the schoolchildren was 24.5%; 16.9% were overweight, and 7.6% were obese. Sex and socioeconomic characteristics were not associated with elevated BP. In all age groups, systolic and diastolic BP correlated with BMI and waist and hip measurements, but not with waist-hip ratio. The prevalence of elevated BP was 11.2% in eutrophic children, 20.6% in overweight children [odds ratio (OR), 1.99; 95% confidence interval (CI), 1.61-2.45], and 39.7% in obese children (OR, 5.4; 95% CI, 4.23-6.89).

Conclusion:

Obese and overweight children had a higher prevalence of elevated BP than normal-weight children. Our data confirm that the growing worldwide epidemic of excess weight and elevated BP in schoolchildren may also be ongoing in Brazil.  相似文献   
13.
Different doses of hepatitis B virus vaccine—prepared by Korea Green Cross Corporation, were given to healthy infants born to HBsAg-negative mothers at birth, 1 and 6 months of age. A dose of 2 μg was administered intradermally in Group A and, in the three other groups, the vaccine was given intramuscularly (i.m.). An adequate follow-up observation was possible for 9 months after birth in 22, 25, 23 and 21 infants in Groups A, B, C and D, respecvely.
Group C (5 μg, i.m.) produced seroconversion most rapidly, showing the highest rate (96%) at 9 months of age. The lowest seroconversion rate (5%) was found at the age of 1 month in Group A subjects, but the rate increased to 91% after a booster dose was given at 6 months of age.
While it can be concluded that a 5 μg i.m. dose of vaccine at 0, 1 and 6 months of age is optimum for the immunization of infants in efficacy and economy, a 2 μg intradermal dose can also be considered as an immunogenic and economical regimen, though the immune response is slower and a special technique is required for immunization.  相似文献   
14.

OBJECTIVES:

Hypertonic saline has been proposed to modulate the inflammatory cascade in certain experimental conditions, including pulmonary inflammation caused by inhaled gastric contents. The present study aimed to assess the potential anti-inflammatory effects of administering a single intravenous dose of 7.5% hypertonic saline in an experimental model of acute lung injury induced by hydrochloric acid.

METHODS:

Thirty-two pigs were anesthetized and randomly allocated into the following four groups: Sham, which received anesthesia and were observed; HS, which received intravenous 7.5% hypertonic saline solution (4 ml/kg); acute lung injury, which were subjected to acute lung injury with intratracheal hydrochloric acid; and acute lung injury + hypertonic saline, which were subjected to acute lung injury with hydrochloric acid and treated with hypertonic saline. Hemodynamic and ventilatory parameters were recorded over four hours. Subsequently, bronchoalveolar lavage samples were collected at the end of the observation period to measure cytokine levels using an oxidative burst analysis, and lung tissue was collected for a histological analysis.

RESULTS:

Hydrochloric acid instillation caused marked changes in respiratory mechanics as well as blood gas and lung parenchyma parameters. Despite the absence of a significant difference between the acute lung injury and acute lung injury + hypertonic saline groups, the acute lung injury animals presented higher neutrophil and tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-8 levels in the bronchoalveolar lavage analysis. The histopathological analysis revealed pulmonary edema, congestion and alveolar collapse in both groups; however, the differences between groups were not significant. Despite the lower cytokine and neutrophil levels observed in the acute lung injury + hypertonic saline group, significant differences were not observed among the treated and non-treated groups.

CONCLUSIONS:

Hypertonic saline infusion after intratracheal hydrochloric acid instillation does not have an effect on inflammatory biomarkers or respiratory gas exchange.  相似文献   
15.
In the present study we investigated the effects of phenolic compounds present in Hypericum perforatum against neuronal excitotoxicity and mitochondrial dysfunction. Quercetin, kaempferol and biapigenin significantly reduced neuronal death caused by 100 microM kainate plus 100 microM N-methyl-D-aspartate. The observed neuroprotection was correlated with prevention of delayed calcium deregulation and with the maintenance of mitochondrial transmembrane electric potential. The three compounds were able to reduce mitochondrial lipid peroxidation and loss of mitochondrial transmembrane electric potential caused by oxidative stress induced by ADP plus iron. Moreover, biapigenin was also able to significantly affect mitochondrial bioenergetics and decrease the capacity of mitochondria to accumulate calcium. Taken together, the results suggest that the neuroprotective action induced by quercetin and kaempferol are mainly mediated by antioxidant effects, whereas biapigenin mainly affects mitochondrial bioenergetics and calcium uptake.  相似文献   
16.
Liver transplantation with monosegment from a living donor   总被引:3,自引:0,他引:3  
The shortage of organ donors for low-weight liver transplant recipients, especially for small children, has led to the development of new surgical techniques to increase the donor pool. Almost all of these techniques use the left lateral segment (Couinaud's segments II and III), but even this graft could be too large for children under 10 kg. We report here the case of an 8-month-old boy, weighing 6.1 kg, who received a monosegmental graft (segment III) from his grandmother weighing 68 kg. The graft was reduced at the donor surgery, before clamping of the vessels. The donor was discharged on the fourth post-operative day; the recipient had an uneventful post-operative period and was discharged after 22 days.  相似文献   
17.
Combined immunosuppression therapy and acute rejection surveillance after heart transplantation may influence clinical outcome. This prospective, longitudinal study investigated 27 pediatric patients (12 days to 12 yr of age; mean 3.0 yr) who underwent a post-operative regimen that included long-term treatment with cyclosporin A and azathioprine (double immunosuppression) and polyclonal anti-thymocyte serum induction therapy. Non-invasive parameters were used to diagnose acute rejection. The actuarial survival, clinical outcomes, and complications were analyzed. The actuarial survival after double immunosuppression and induction therapy with polyclonal anti-thymocyte serum was 89%, 73%, and 57% at 1, 4, and 8 yr, respectively. The rejection frequency was 2.6 episodes/patient and the infection frequency, 3.7 episodes/patient. One year after transplantation, systemic arterial hypertension was detected in 21% of patients. Hence, double immunosuppression with polyclonal anti-thymocyte serum induction therapy combined with surveillance of acute rejection with non-invasive tests may provide promising clinical outcome in pediatric heart transplant recipients.  相似文献   
18.

OBJECTIVE:

This study was designed to evaluate the effects of terlipressin versus fluid resuscitation with normal saline, hypertonic saline or hypertonic-hyperoncotic hydroxyethyl starch, on hemodynamics, metabolics, blood loss and short-term survival in hemorrhagic shock.

METHOD:

Twenty-nine pigs were subjected to severe liver injury and treated 30 min later with either: (1) 2 mg terlipressin in a bolus, (2) placebo-treated controls, (3) 4 mL/kg 7.5% hypertonic NaCl, (4) 4 mL/kg 7.2% hypertonic-hyperoncotic hydroxyethyl starch 200/0.5, or (5) normal saline at three times lost blood volume.

RESULTS:

The overall mortality rate was 69%. Blood loss was significantly higher in the hypertonic-hyperoncotic hydroxyethyl starch and normal saline groups than in the terlipressin, hypertonic NaCl and placebo-treated controls groups (p<0.005). Hyperkalemia (K>5 mmol/L) before any treatment occurred in 66% of the patients (80% among non-survivors vs. 22% among survivors, p=0.019). Post-resuscitation hyperkalemia occurred in 86.66% of non-survivors vs. 0% of survivors (p<0.001). Hyperkalemia was the first sign of an unsuccessful outcome for the usual resuscitative procedure and was not related to arterial acidemia. Successfully resuscitated animals showed a significant decrease in serum potassium levels relative to the baseline value.

CONCLUSION:

Hyperkalemia accompanies hemorrhagic shock and, in addition to providing an early sign of the acute ischemic insult severity, may be responsible for cardiac arrest related to hemorrhagic shock.  相似文献   
19.
Previous studies have shown that tumour cells from low-grade B-cell gastric lymphomas of mucosa-associated lymphoid tissue (MALT) type proliferate in vitro in response to heat-killed whole cell preparations of Helicobacter pylori , but only in the presence of tumour-infiltrating T cells. This response is strain-specific in that the tumours studied responded optimally to different strains of H. pylori . It was unclear from these studies, however, whether the ability to recognize the specific stimulating strains of H. pylori was a property of the tumour cells or the tumour-infiltrating T cells. This study shows that whereas the tumour cells do not respond to H. pylori , both freshly isolated tumour-infiltrating T cells and a T cell line derived from these cells proliferate in response to stimulating strains of H. pylori . T cells from the spleen of one of the patients do not share this property. These results suggest that B-cell proliferation in cases of low-grade gastric lymphoma of MALT type in vitro in response to H. pylori is due to recognition of H. pylori by tumour-infiltrating T cells, which in turn provide help for tumour cell proliferation. The observations provide an explanation for properties of gastric MALT-type lymphoma, such as regression following eradication of H. pylori and the tendency of the tumour to remain localized to the primary site.  相似文献   
20.
Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future.  相似文献   
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