Are vertical meridian effects due to audio-visual interference? A new confirmation with deaf subjects

Purpose. Specific increases of reaction times (RTs) were found in normal subjects, when endogenous spatial cues and targets were separated by the vertical visual meridian (VM) or by the vertical auditory (AM) meridian, when targets were either visual or auditory. The aim of this study was to assess if this effect could be attributed to longer RTs needed to shift activation between the hemispheres, or rather to different spatial maps underlying visual and auditory attention.

Method. We tested the VM effect in deaf subjects. If the shifting of activation from one hemisphere to the other causes the increase in RTs, then no differences between normal and sensory disabled people should take place, as the incoming perceptual information in the residual modality uses the same neural pathways while crossing the vertical meridian. Conversely, if the vertical meridian effects are related to the spatial representation systems underlying endogenous orienting mechanisms, then the lack of the auditory perceptual system in deaf people may have determined different organization processes in the brain circuits, strongly affecting the orienting mechanisms of spatial attention.

Results. Compared with a control group of hearing subjects, we found no evidence of the VM effect in deaf subjects.

Conclusions. This finding, jointly with those of a previous experiment which showed no AM effect on blind subjects (Olivetti Belardinelli & Santangelo 2005) supports the idea of different spatial maps underlying visual and auditory attention, and suggests that their co-existence may induce interference effects in space processing, giving rise to the anisotropic representation of visual and auditory spaces, observed in normal subjects.     

Type IIB von Willebrand factor with normal sialic acid content induces platelet aggregation in the absence of ristocetin. Role of platelet activation, fibrinogen, and two distinct membrane receptors.

Three preparations of purified von Willebrand factor (vWF), obtained from unrelated patients affected by type IIB von Willebrand disease, were found to have normal sialic acid content (between 129 and 170 nmol/mg of vWF, as compared with 158 +/- 17 nmol/mg in four normal preparations) and to induce platelet aggregation in the presence of physiologic levels of divalent cations and without addition of ristocetin. A monoclonal antibody that blocks the vWF binding domain of the platelet glycoprotein (GP)Ib caused complete inhibition of IIB vWF-induced aggregation. In contrast, a monoclonal antibody that blocks the receptor for adhesive proteins on the platelet GPIIb/IIIa complex failed to inhibit the initial response of platelets to high concentrations of IIB vWF. Moreover, IIB vWF caused agglutination of formalin-fixed platelets that was blocked only by the anti-GPIb antibody, suggesting that the binding of vWF to GPIb, even in the absence of ristocetin, results in platelet-platelet interaction that is followed by exposure of the GPIIb/IIIa receptors for adhesive proteins. Endogenous ADP, normally active platelet metabolism and fibrinogen binding to GPIIb/IIIa were necessary for maximal and irreversible platelet aggregation. In the absence of fibrinogen, however, aggregation was mediated by vWF binding to GPIIb/IIIa. A 52/48-kD tryptic fragment containing the GPIb binding domain of normal vWF completely blocked the aggregation induced by all three IIB vWF preparations. The present study defines in detail the mechanisms involved in IIB vWF-induced platelet aggregation. Moreover, it establishes that the GPIb binding domain of normal and IIB vWF are closely related and that desialylation is not required for the direct interaction of IIB vWF with GPIb.     

World Health Organization disability assessment schedule 2.0: An international systematic review

Purpose: This systematic review examines research and practical applications of the World Health Organization Disability Assessment Schedule (WHODAS 2.0) as a basis for establishing specific criteria for evaluating relevant international scientific literature. The aims were to establish the extent of international dissemination and use of WHODAS 2.0 and analyze psychometric research on its various translations and adaptations. In particular, we wanted to highlight which psychometric features have been investigated, focusing on the factor structure, reliability, and validity of this instrument.

Method: Following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) methodology, we conducted a search for publications focused on “whodas” using the ProQuest, PubMed, and Google Scholar electronic databases.

Results: We identified 810 studies from 94 countries published between 1999 and 2015. WHODAS 2.0 has been translated into 47 languages and dialects and used in 27 areas of research (40% in psychiatry).

Conclusions: The growing number of studies indicates increasing interest in the WHODAS 2.0 for assessing individual functioning and disability in different settings and individual health conditions. The WHODAS 2.0 shows strong correlations with several other measures of activity limitations; probably due to the fact that it shares the same disability latent variable with them.

• Implications for Rehabilitation

• WHODAS 2.0 seems to be a valid, reliable self-report instrument for the assessment of disability.

• The increasing interest in use of the WHODAS 2.0 extends to rehabilitation and life sciences rather than being limited to psychiatry.

• WHODAS 2.0 is suitable for assessing health status and disability in a variety of settings and populations.

• A critical issue for rehabilitation is that a single “minimal clinically important .difference” score for the WHODAS 2.0 has not yet been established.

     

Quantitative analysis of bile acids in human plasma by liquid chromatography-electrospray tandem mass spectrometry: a simple and rapid one-step method.

Bile acids play a pivotal role in the metabolism of cholesterol and lipids. Their blood concentrations are important prognostic and diagnostic indicators of hepatobiliary and intestinal dysfunction. This class of molecules comprises a heterogeneous group of compounds with a common cholesterol scaffold. Recently, the introduction of liquid chromatography coupled to tandem mass spectrometry methods has revealed an innovative path in the quantisation of specific bile acids in biological specimens. A robust and sensitive method has been developed based on high performance liquid chromatography separation coupled to an electrospray triple-quadrupole mass spectrometer. Human plasma samples were analysed on a C18 reverse-phase column. The elution profiles were monitored in multiple reaction-monitoring mode, quantifying and identifying each analyte by its own unique precursor to product patterns. A linear correlation over a broad range of bile acid concentrations (0.1-100 microM) was observed. The average recovery period for all of the analysed bile acids was 98 +/- 3%. Intra-day and inter-day precision averages were 2% and 5.4%, respectively. The determination was achieved within a single chromatographic run for all unconjugated, glycine- and taurine-conjugated isomeric forms of bile acids. As a proof of principle this method has been validated on a small subset of cholestatic patients (n = 7) and compared to appropriate clinical controls (n = 10). Based upon our encouraging experimental results, the described HPLC separation coupled to tandem mass spectrometry method for the analysis of bile acids in biological samples is deemed a robust and accurate procedure. Consequently, we propose this technique as a suitable candidate method for the identification and quantitation of bile acids in routine analysis.     

Diffuse idiopathic skeletal hyperostosis: an uncommon case of dysphagia in an older adult

Diffuse idiopathic skeletal hyperostosis (DISH) is a common disorder among older adults. It is characterized by ossification of the anterior longitudinal ligament of the spine and various extra-spinal ligaments. Although stiffness and decreased range of motion of the spine are the most common clinical presentations of DISH, extra-skeletal manifestations may also be present. We report the case of a 65-year-old man complaining of progressive dysphagia due to DISH. Barium swallow showed compression and lateral displacement of the cervical tract of the esophagus, secondary to compression by a large osteophyte. The patient received medical treatment with COX-2 inhibitors and liquid diet. In conclusion, DISH should be considered an important, although rare, cause of dysphagia among older adults. However, it should not be accepted as the cause of dysphagia until all other causes have been ruled out.     

Correlation of lipoprotein(a) levels and myocardial stress thallium scintigraphy pattern in different entities of CHD severity

BACKGROUND: Higher levels of lipoprotein(a) confer an increased risk for coronary heart disease (CHD). Apo-E genotype (APO-E) also plays a role, the APO-E epsilon 4 allele being associated with CHD. Furthermore, higher Lp(a) concentrations are correlated with APO-E epsilon 4 allele presence. The study was performed to investigate the relationship of Lp(a) and APO-E with the functional status of coronary arteries as evaluated by myocardial scintigraphy. PATIENTS AND METHODS: We studied 70 patients (27 F and 43 M; mean age: 55 +/- 6 yrs.) consecutively referred for CHD, and 50 normal sex and age-matched controls. Total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, apo-AI, apo-B, Lp(a) levels (ELISA), Lp(a) isoforms (Immuno Blotting) and APO-E (PCR) were measured in all subjects. Only CHD patients underwent a myocardial tomographic stress thallium scintigraphy (201Tl-SPECT); the SPECT pattern was classified as follows: no perfusion defects (unstable angina group = 1), reversible defects at stress images (ischemia group = 2), fixed defects (infarction group = 3). RESULTS: Lp(a) medians were significantly higher than controls in group 1 (p < 0.05), 2 (p < 0.001) and 3 (p = 0.00). Low molecular weight isoforms (B, S1, S2) were significantly more frequent in all CHD-patients vs. controls (p < 0.05), whereas APO-E genotypes did not differ among controls and patients. Multiple regression analysis showed family history (p < 0.001) to be the only independent predictive variable of CHD severity correlated to the scintigraphic pattern. CONCLUSION: Among the considered biological parameters in our patients only Lp(a) plasma levels are related to the entity of ischemic cardiac wall damage as evaluated by 201Tl-SPECT.     

Impaired endothelial antithrombotic activity following short-term interruption of continuous subcutaneous insulin infusion in type 1 diabetic patients

Review of literature has shown an increased rate of thrombotic complications in diabetic patients with frequent episodes of hyperketonemia. However, the mechanisms by which ketosis promotes vascular disease in diabetic patients are unclear. It was the aim of this study to investigate early changes in haemostatic parameters and oxidative stress markers during the hyperketonemic status which follows the interruption of continuous subcutaneous insulin infusion (CSII) in type I diabetic patients. Eight CSII-treated type I diabetic patients underwent a 4-hour pump arrest. Blood glucose, insulin and 3-hydroxybutirate were measured to verify the metabolic response. A vein-occlusive (VO) test was performed for the determination of tPA and PAI-1 activities and their antigen levels before and after the CSII arrest. Coagulation factor VII and VIII were evaluated by one-stage PT and PTT method, respectively. TF, vWF, tPA and PAI-1 antigens were determined by ELISA, whereas tPA and PAI-1 activities using chromogenic methods. Plasma malondialdehyde (MDA) and protein carbonyl groups (PCG) levels were determined by HPLC and spectrophotometry, respectively. After the insulin deprivation phase, post-VO tPA antigen level significantly decreased (P = 0.0391), whereas TF and post-VO PAI-1 activity and antigen levels significantly increased (P = 0.0156 and P = 0.0234, respectively). Plasma MDA and PCG levels were 1.88-fold and 1.74-fold higher than baseline values, respectively. In conclusion, the impairment of the fibrinolytic potential and the increases in TF, MDA and PCG levels may enhance the risk of both arterial and venous thrombosis during ketosis. Thus, early detection of hyperketonemia in DM patients could contribute to the prevention of life-threatening vascular events.