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961.
BACKGROUND: Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) is an inherited arrhythmia syndrome, characterised by polymorphic ventricular tachycardia induced by adrenergic stress. CPVT can be caused by mutations the cardiac ryanodine receptor gene (RYR2) or mutations in the cardiac calsequestrin gene CASQ2. Structural heart disease is usually absent and the baseline ECG is usually normal. Patients with CPVT often present with exercise- or emotion induced syncope, the first presentation can also be sudden cardiac death. MANAGEMENT: Besides removal of triggers treatment with beta blockers is currently a class I indication in clinically diagnosed patients. Beta blockage should be titrated up to an effective level. The addition of flecainide seems to be a promising approach in patients where arrhythmias are not completely suppressed by beta blockers. A cardioverter-defibrillator (ICD) or left cervical sympathetic denervation might be considered under special circumstances. Genetic counselling is recommended and all first degree relatives should be properly evaluated.  相似文献   
962.
A 52-year-old woman with Takayasu arteritis and a known history of multiple sclerosis had been treated with subcutaneous interferon (IFN) beta-1α. After the re-introduction of the IFN beta-1α, the patient had a gradual worsening of the arteritis, with claudication symptoms in the left arm and increased inflammation markers. An evaluation using Doppler ultrasound of the supra-aortic vessels revealed severe stenosis of the left axillary artery. The IFN beta-1α was withdrawn, with prompt clinical and laboratory improvement of the vasculitis.  相似文献   
963.
J Clin Hypertens (Greenwich). 2012;00:00–00. ©2012 Wiley Periodicals, Inc. The benefit obtained from antihypertensive treatment is related more to overall cardiovascular risk reduction than to blood pressure levels. Accurate implementation of cardiovascular diagnostics is a key step toward assessment of cardiovascular risk. In the 3A Registry study, data about patient history, concomitant diseases, diagnostic procedures, and medications were prospectively collected. A total of 14,738 patients recruited by 899 physicians in 2008 and 2009 were analyzed. Assessment of cardiovascular risk factors and subclinical end‐organ damage (SOD) showed broad differences in the implementation of European Society of Hypertension/European Society of Cardiology recommendations. Electrocardiograms were available in 59% of patients, cholesterol in 71.4%, and glucose in 69.7%. Almost all patients (99.6%) had creatinine measurements performed and microalbuminuria was measured in 8.5%. Metabolic syndrome (MS) had been evaluated in 59.7%. Implementation of diagnostic guidelines was highest in hypertensive patients with diabetes, followed by patients with known cardiovascular disease and established chronic renal insufficiency. For hypertensive patients without known comorbidities, the authors estimated that up to 29% had missed SOD (detection rate <50%) and 13% missed MS due to incomplete assessment of risk factors. This large registry study shows that assessment for cardiovascular risk factors and SOD is incomplete. Major efforts are required to improve comprehensive hypertension management as recommended by current guidelines.  相似文献   
964.
ABSTRACT: BACKGROUND: MCAD-deficiency is the most common inborn error of fatty acid oxidation now included in many newborn screening programms using MS/MS. During prolonged catabolic episodes, patients may suffer from metabolic decompensation with dysfunction of liver, skeletal- and heart muscle as well as brain. In anabolism, neither clinical symptoms nor biochemical signs of organ dysfunction occur. CASE PRESENTATION: We report a female patient with MCAD-deficiency in whom at the age of 11 years isolated AST-elevation was found without any clinical or biochemical signs of organ dysfunction. We showed by polyethylene glycol precipitation that macro-AST formation was responsible for this biochemical finding. AST was probably complexed with immunoglobulins possibly related to an allergic disposition. Macro-AST formation is not a special feature of MCAD-deficiency but rather a non-specific, coincidental finding which also occurs in healthy individuals. The general practitioner consulted by the patient before coming to our outpatient clinic for inborn errors of metabolism was worried that isolated AST-elevation indicated cell damage in MCAD-deficiency. He ordered further diagnostic tests like ultrasound, ECG and echocardiography without any pathology. CONCLUSION: In isolated AST-elevation, macro-AST has to be considered in order to avoid unnecessary, costly and invasive evaluation. This is not only true for healthy persons but for patients with chronic diseases like MCAD as well.  相似文献   
965.

Background

Previous controlled studies on the effect of non-pharmaceutical interventions (NPI) - namely the use of facemasks and intensified hand hygiene - in preventing household transmission of influenza have not produced definitive results. We aimed to investigate efficacy, acceptability, and tolerability of NPI in households with influenza index patients.

Methods

We conducted a cluster randomized controlled trial during the pandemic season 2009/10 and the ensuing influenza season 2010/11. We included households with an influenza positive index case in the absence of further respiratory illness within the preceding 14 days. Study arms were wearing a facemask and practicing intensified hand hygiene (MH group), wearing facemasks only (M group) and none of the two (control group). Main outcome measure was laboratory confirmed influenza infection in a household contact. We used daily questionnaires to examine adherence and tolerability of the interventions.

Results

We recruited 84 households (30 control, 26 M and 28 MH households) with 82, 69 and 67 household contacts, respectively. In 2009/10 all 41 index cases had a influenza A (H1N1) pdm09 infection, in 2010/11 24 had an A (H1N1) pdm09 and 20 had a B infection. The total secondary attack rate was 16% (35/218). In intention-to-treat analysis there was no statistically significant effect of the M and MH interventions on secondary infections. When analysing only households where intervention was implemented within 36 h after symptom onset of the index case, secondary infection in the pooled M and MH groups was significantly lower compared to the control group (adjusted odds ratio 0.16, 95% CI, 0.03-0.92). In a per-protocol analysis odds ratios were significantly reduced among participants of the M group (adjusted odds ratio, 0.30, 95% CI, 0.10-0.94). With the exception of MH index cases in 2010/11 adherence was good for adults and children, contacts and index cases.

Conclusions

Results suggest that household transmission of influenza can be reduced by the use of NPI, such as facemasks and intensified hand hygiene, when implemented early and used diligently. Concerns about acceptability and tolerability of the interventions should not be a reason against their recommendation.

Trial registration

The study was registered with ClinicalTrials.gov (Identifier NCT00833885).  相似文献   
966.
967.
PurposeTo refine estimates of macular soft drusen abundance in eyes with age-related macular degeneration (AMD) and evaluate hypotheses about drusen biogenesis, we investigated topographic distribution and growth rates of drusen by optical coherence tomography (OCT). We compared results to retinal features with similar topographies (cone density and macular pigment) in healthy eyes.MethodsIn a prospective study, distribution and growth rates of soft drusen in eyes with AMD were identified by human observers in OCT volumes and analyzed with computer-assistance. Published histologic data for macular cone densities (n = 12 eyes) and in vivo macular pigment optical density (MPOD) measurements in older adults with unremarkable maculae (n = 31; 62 paired eyes, averaged) were revisited. All values were normalized to Early Treatment Diabetic Retinopathy Study (ETDRS) subfield areas.ResultsSixty-two eyes of 44 patients were imaged for periods up to 78 months. Soft drusen volume per unit volume at baseline is 24.6-fold and 2.3-fold higher in the central ETDRS subfield than in outer and inner rings, respectively, and grows most prominently there. Corresponding ratios (central versus inner and central versus outer) for cone density in donor eyes is 13.3-fold and 5.1-fold and for MPOD, 24.6 and 23.9-fold, and 3.6 and 3.6-fold.ConclusionsNormalized soft drusen volume in AMD eyes as assessed by OCT is ≥ 20-fold higher in central ETDRS subfields than in outer rings, paralleling MPOD distribution in healthy eyes. Data on drusen volume support this metric for AMD risk assessment and clinical trial outcome measure. Alignment of different data modalities support the ETDRS grid for standardizing retinal topography in mechanistic studies of drusen biogenesis.  相似文献   
968.
PurposeWe aimed to investigate the reactivity of retinal vessels to a flickering stimulus in patients with age-related macular degeneration (AMD) and healthy participants. We also assessed whether the parameters of retinal vessels are dependent on genetic predisposition.MethodsA total of 354 patients with AMD and 121 controls were recruited for the study. All participants underwent thorough ophthalmologic examination and static and dynamic retinal vessel analysis. AMD risk polymorphisms were genotyped in the CFH and ARMS2 genes.ResultsWe found no differences between the AMD group and controls in central retinal arteriolar equivalent (CRAE), central retinal venular equivalent (CRVE), arteriovenous ratio (AVR), dynamic analysis of arteries (DAAs), or dynamic analysis of veins (DAVs). Eyes with early AMD presented with significantly higher AVR values than eyes with late AMD. In the AMD group, DAA correlated positively with both choroidal thickness (Rs = 0.14, P = 0.00096) and choroidal volume (Rs = 0.23, P < 0.0001), and no such associations were observed in the controls. We found significantly lower DAA (1.47 ± 1.50) in TT homozygotes for the ARMS2 A69S polymorphism in comparison with GG homozygotes (2.38 ± 1.79) and patients with GG + GT genotypes (2.28 ± 1.84). We also observed less prominent DAV (3.24 ± 1.71) in patients with TC + CC genotypes in the CFH Y402H polymorphism compared with TT homozygotes (3.83 ± 1.68).ConclusionsOur findings suggest that retinal microcirculation appears to be associated with the genetic background, choroidal parameters, and clinical features of the patients with AMD.  相似文献   
969.
Background.?Studies about transmission rates of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae in hospitals and households are scarce. Methods.?Eighty-two index patients with new carriage of ESBL-producing Escherichia coli (ESBL-Ec; n?=?72) or ESBL-producing Klebsiella pneumoniae (ESBL-Kp; n?=?10) and their hospital (n?=?112) and household (n?=?96) contacts were studied prospectively from May 2008 through September 2010. Isolates were phenotypically and molecularly characterized (sequencing of bla genes, repetitive extragenic palindromic polymerase chain reaction, pulse-field gel electrophoresis, and multilocus sequence typing). Transmission was defined as carriage of a clonally-related ESBL producer with identical bla(ESBL) gene(s) in the index patient and his or her contact(s). Results.?CTX-M-15 was the most prevalent ESBL in ESBL-Ec (58%) and ESBL-Kp (70%) in the index patients. Twenty (28%) ESBL-Ec isolates were of the hyperepidemic clone ST131. In the hospital, transmission rates were 4.5% (ESBL-Ec) and 8.3% (ESBL-Kp) and the incidences of transmissions were 5.6 (Ec) and 13.9 (Kp) per 1000 exposure days, respectively. Incidence of ESBL-Kp hospital transmission was significantly higher than that of ESBL-Ec (P?相似文献   
970.
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