The Pulfrich Phenomenon: Practical Implications of the Assessment of Cases and Effectiveness of Treatment

The Pulfrich phenomenon, originally described in normal observers, is a treatable disorder of the perception of movement in depth in cases of unilateral or asymmetric optic neuropathy. Treatment is highly bespoke and factors influencing treatment response and failure remain unclear. We assessed 25 adults with suspected Pulfrich phenomenon due to a range of conditions in two tertiary referral centres. Monocularly tinted spectacles were successful in reducing symptoms of the Pulfrich phenomenon under daylight conditions in nine subjects, eight of whom had optic neuritis. These spectacles were not effective at night and in patients with visual field defects due to ischaemic optic neuropathy, glaucoma, optic disc drusen or severe peripapillary retinal nerve fibre loss on optical coherence tomography.     

Continuous Cardiac Output in Septic Shock by Simulating a Model of the Aortic Input Impedance: A Comparison with Bolus Injection Thermodilution

Background: To compare continuous cardiac output obtained by simulation of an aortic input impedance model to bolus injection thermodilution (TDCO) in critically ill patients with septic shock.

Methods: In an open study, mechanically ventilated patients with septic shock were monitored for 1 (32 patients), 2 (15 patients), or 3 (5 patients) days. The hemodynamic state was altered by varying the dosages of dopamine, norepinephrine, or dobutamine. TDCO was estimated 189 times as the series average of four automated phase-controlled injections of iced 5% glucose, spread equally over the ventilatory cycle. Continuous model-simulated cardiac output (MCO) was computed from radial or femoral artery pressure. On each day, the first TDCO value was used to calibrate the model.

Results: TDCO ranged from 4.1 to 18.2 l/min. The bias (mean difference between MCO and TDCO) on the first day before calibration was -1.92 +/- 2.3 l/min (mean +/- SD; n = 32; 95% limits of agreement, -6.5 to 2.6 l/min). The bias increased at higher levels of cardiac output (P < 0.05). In 15 patients studied on two consecutive days, the precalibration ratio TDCO:MCO on day 1 was 1.39 +/- 0.28 (mean +/- SD) and did not change on day 2 (1.39 +/- 0.34). After calibration, the bias was -0.1 +/- 0.8 l/min with 82% of the comparisons (n = 112) < 1 l/min and 58% (n = 79) < 0.5 l/min, and independent of the level of cardiac output.     

Myocardial strain and torsion quantified by cardiovascular magnetic resonance tissue tagging: studies in normal and impaired left ventricular function.

Accurate quantification and timing of regional myocardial function allows early identification of dysfunction, and therefore becomes increasingly important for clinical risk assessment, patient management, and evaluation of therapeutic efficacy. For this purpose, the application of tissue Doppler echocardiography has rapidly increased. However, echocardiography has some major inherent limitations. Cardiovascular magnetic resonance imaging with tissue tagging provides highly reproducible data on myocardial function, not only in longitudinal and radial directions, but also in the circumferential direction. Because of the development of faster imaging protocols, improved temporal resolution, less time-consuming postprocessing procedures, and the potential of quantifying myocardial deformation in 3 dimensions at any point in the heart, this technique may serve as an alternative for tissue Doppler echocardiography and is now ready for more widespread clinical use. This review discusses the clinical use of cardiovascular magnetic resonance tissue tagging for quantitative assessment of regional myocardial function, thereby underlining the specific features and emerging role of this technique.     

The plasminogen activator inhibitor-1 (PAI-1) promoter haplotype is related to PAI-1 plasma concentrations in lean individuals

BACKGROUND: Elevated plasminogen activator inhibitor-1 (PAI-1) concentrations are associated with cardiovascular diseases. PAI-1 antigen levels are influenced by environmental factors such as body mass index (BMI), and by genetic factors. The PAI-1 promoter of the PAI-1 gene contains two common polymorphisms (-844A/G and -675(4G/5G)) and the 4G allele of the -675(4G/5G) variation has been associated with elevated PAI-1 concentrations and on some occasions with an increased risk of cardiovascular disease. OBJECTIVES: The aim of our study was to investigate the effect of the PAI-1 promoter haplotype on PAI-1 concentrations and to determine the role of BMI. METHODS: The association between the PAI-1 promoter haplotype and PAI-1 antigen levels was investigated in two independent populations, each including 600 healthy Caucasians. Furthermore, to assess the effect of the PAI-1 promoter haplotype on PAI-1 promoter activity, in vitro reporter gene assays were performed in HepG2 and BAEC cells. RESULTS: We observed significantly higher PAI-1 concentrations in A-4G homozygotes than in G-5G carriers in lean subjects (BMI in the lowest quartile). In these lean subjects, the PAI-1 concentrations in A-4G/G-5G heterozygotes were reduced to 60-75%, and the concentrations in G-5G homozygotes to 45-55%, compared to the PAI-1 concentrations of A-4G homozygotes (p < 0.01). PAI-1 concentrations increased approximately four-fold from the lowest to the highest BMI quartile (p < 0.01). The reporter gene assays did not support a direct effect of the PAI-1 promoter haplotype on promoter activity in HepG2 or BEAC cells. CONCLUSIONS: Our study suggests that the PAI-1 promoter haplotype and BMI affect PAI-1 concentrations and that BMI is a stronger determinant than PAI-1 promoter variation.     

Low Density Lipoprotein Apheresis Improves Regional Myocardial Perfusion in Patients With Hypercholesterolemia and Extensive Coronary Artery Disease: The LDL-Apheresis Atherosclerosis Regression Study (LAARS)

Objectives. In a randomized study we evaluated the effect of biweekly low density lipoprotein (LDL) apheresis plus simvastatin versus medication alone on regional myocardial perfusion.

Background. In patients with severe hypercholesterolemia, diet and lipid-lowering drugs are often insufficient to achieve optimal LDL cholesterol values. Low density lipoprotein apheresis is a very effective lipid-lowering therapy. Assessment of regional myocardial perfusion enables evaluation of the functional state of the coronary circulation.

Methods. We studied 42 patients with severe hypercholesterolemia and extensive coronary artery disease who were randomized to diet and simvastatin with or without biweekly LDL apheresis. Regional myocardial perfusion was assessed by digital subtraction angiography with videodensitometric calculation of hyperemic mean transit time (HMTT) of contrast medium at baseline and after 2 years of therapy.

Results. Low density lipoprotein cholesterol decreased by 63% (to 3.0 mmol/liter) in the LDL apheresis group and by 47% (to 4.1 mmol/liter) in the medication group. Paired HMTT measurements were assessed in 43 regions in the LDL apheresis group and 35 regions in the medication group. In the LDL apheresis group, regional HMTT decreased over 2 years from 3.35 ± 1.18 (mean ± SD) to 2.87 ± 0.82 s (−14%, p = 0.001), whereas no change in the medication group was observed: 2.95 ± 1.06 to 2.96 ± 0.90 s (p = NS). In the patient-based comparison, the mean change in HMTT was −0.45 s (−14%, p = 0.01) in the LDL apheresis group and −0.05 s (−2%, p = NS) in the medication group, respectively. Only exercise-induced ischemia improved in the LDL apheresis group.

Conclusions. Biweekly LDL apheresis plus simvastatin decreased time-averaged LDL cholesterol levels by an additional 31% (1.1 mmol/liter) compared with medication alone. After 2 years of therapy, regional myocardial perfusion improved in the LDL apheresis group and remained unchanged in the medication group. Thus, aggressive reduction of LDL cholesterol has a favorable effect on regional myocardial perfusion and alleviates ischemia.

(J Am Coll Cardiol 1996;28:1696–704)>     

Examining relationships between staff attributions of soundscapes and core affect in people with severe or profound intellectual and visual disabilities

Background People with profound intellectual disability experience a high prevalence of visual disability, making them more dependent on sound. However, research addressing the influence of the auditory environment is scarce.

Method Observations of the auditory environments (soundscapes) and moods of people with profound intellectual and visual disabilities, in terms of core affect, were conducted in residential facilities by direct support personnel. Appraisals of soundscape and core affect dimensions were combined and analysed by means of multilevel linear regression.

Results Findings endorse a positive relationship between the observed pleasantness and eventfulness of soundscapes and core affect of people with profound intellectual and visual disabilities.

Conclusion Based on the results of this study we suggest a relationship between soundscapes and moods of people with profound intellectual and visual disabilities, as judged by staff members engaged in their environments. These findings give reason to believe that improved soundscapes could ameliorate the moods of the residents.     

Preexisting poliovirus-specific IgA in the circulation correlates with protection against virus excretion in the elderly

BACKGROUND: Epidemiological studies have indicated that at least 10% of the Dutch elderly do not have poliovirus serotype-specific neutralizing antibody titers and might be at risk for poliovirus infection. Previously we established that memory immunity does not protect the elderly against poliovirus replication. In this study, we investigated whether preexisting immunoglobulin (Ig) A protects against poliovirus infection. METHODS: Elderly individuals (n = 383), divided into seronegative and seropositive groups, were challenged with monovalent oral poliovirus vaccine (mOPV), either serotype 1 or serotype 3. After challenge, poliovirus serotype-specific circulating and salivary IgA responses were measured by enzyme-linked immunosorbent assays, and poliovirus excretion in stool was measured. RESULTS: The majority of elderly persons without preexisting IgA excreted poliovirus in the stool. In contrast, most elderly persons seropositive for IgA did not excrete poliovirus. Significant inverse correlations were found between preexisting titers of poliovirus serotype-specific circulating IgA and virus excretion. Challenge with mOPV (re)induced IgA responses; low salivary IgA responses correlated with that in the circulation but not with virus excretion. CONCLUSIONS: These results indicate that preexisting IgA values in the circulation correlate with protection against poliovirus infection in the elderly. This further implies that persons without preexisting IgA might contribute to the circulation of poliovirus and therefore may threaten its eradication.