Early detection with speckle tracking echocardiography of biventricular systolic dysfunction, and its relationship with fatigue, in patients with multiple sclerosis

Funding Acknowledgements

Type of funding sources: None.

Background

Fatigue is a frequent and debilitating symptom of multiple sclerosis (MS), affecting 90% of patients. Symptoms seems multifactorial, but little is known about the contribution of cardiovascular morpho-functional alterations linked to comorbidities, to lifestyle, to MS itself or to drugs (i.e. mitoxantrone).

Aim

to investigate the presence of cardiac alterations in MS patients, and to evaluate their impact on fatigue.

Methods

 24 patients with relapsing-remitting MS (RR-MS) underwent an electrocardiogram (ECG), a transthoracic echocardiographic (TTE), a six minutes walking test (6MWT) with Borg scale (BS), and two fatigue self-assessment scales, the Fatigue Severity Scale (FSS) and the Modified Fatigue Impact Scale (MFIS). The patients were divided into 2 groups: group 1, without traditional cardiovascular risk factors (CVRF: smoke, hypertension, diabetes, hypercholesterolemia; n = 12, 11 females), and group 2, with at least one CVRF (n = 12, 5 females). None of the patients had ever been on mitoxantrone therapy. No new control group was studied due to the SARS-CoV-2 pandemic restrictions , so the comparison was performed with general healthy population in internationally validated previous studies.

Results

No arrhythmias were found. In both MS groups all the TTE left ventricular (LV) systolic function parameters were depressed compared to the healthy population, but only the mean global longitudinal strain (GLS), the mean longitudinal strain rate (LSR) of LV and estimated pulmonary artery systolic pressure (PAPs) were statistically significant depressed compared to the healthy general population (p < 0.005): see table. This reduction was observed in both MS groups, while there were non significant differences among the two groups. TTE LV function depression significantly correlated to variation of parameters of fatigue , especially considering LV GLS in relation to BS values.

Conclusions

Subclinical biventricular systolic dysfunction is present in MS patients, and it seems to be linked to the disease itself without being influenced by CVRF. This dysfunction, detected by speckle tracking echocardiographic techniques, seems to contribute to the symptom of fatigue in patients with MS. It is important to include TTE in the workup and follow-up of MS patients, in order to promptly treat cardiac dysfunction and relieve fatigue.

Professional education in curricular internships of occupational therapists in Primary Health Care

This study regards the experience of implementing a professional internship intended to students of Occupational Therapy in Primary Health Care in a Federal University located in São Paulo State, Brazil. Occupational therapist profession in Brazil was inserted in this level of care to offer specialised support to teams, mainly concerning qualification of care to vulnerable and invisible populations (community, family and cultural aspects), health promotion, encouragement of team work, humanisation in health. Such curricular internship occurs since 2017 to students of the 4th and 5th years of undergraduate course, completing 240 hours. How is the practice programme in Primary Health Care organised in the pedagogic project? Which are the strengths and fragilities of this field, as far as education is concerned? Among the practice scenarios, there are Basic Health Unit, Family Health Strategy teams, Family Health Support Centre, Street Clinic and University Basic Health Unit, with tutors who establish the collaboration. The interns follow individual and group cases, take part in team meetings and actions for team qualification and are also supervised weekly by a professor. Among their strengths, we can list a diversified education, based on the most recent public policies for the level of care that represents the stepping stone to the health system. As well as the access to the occupational therapy professional in this first contact, if the team identifies such necessity. Regarding challenges, there is unawareness about professional practice, difficulty to access work instruments and resources, as well as physical space. We hope this experience can help other educational institutions to implement their practice programmes in and for the health system. Egresses report that enables learning to work in a team in different scenarios. Such strategy aims to form a generalist professional, with criticality regarding challenges and potentialities of Brazilian public health.

Key messages

This study reports the experience of a professional internship of Occupational Therapy in Primary Health Care, understanding the health system as a scenario for practice, teaching and learning. Educating occupational therapists to this level of care is necessary, in agreement with the attributes of Primary Care.

Electronic correlations stabilize the antiferromagnetic Mott state in Cs3C60

Cs(3)C(60) in the A15 structure is an antiferromagnet at ambient pressure in contrast with other superconducting trivalent fullerides. Superconductivity is recovered under pressure and reaches the highest critical temperature of the family. Comparing density-functional calculations with generalized gradient approximation to the hybrid functional of Heyd, Scuseria, and Ernzerhof, which includes a suitable component of exchange, we establish that the antiferromagnetic state of Cs(3)C(60) is not due to a Slater mechanism, and it is stabilized by electron correlation. Pressure reduces the stability of the antiferromagnetic state. Our findings corroborate previous analyses suggesting that the properties of this compound can be understood as the result of the interplay between electron correlations and Jahn-Teller electron-phonon interaction.

Noise correlations and SNR in phased-array MRS

The acquisition of magnetic resonance spectroscopy (MRS) signals by multiple receiver coils can improve the signal-to-noise ratio (SNR) or alternatively can reduce the scan time maintaining a reliable SNR. However, using phased array coils in MRS studies requires efficient data processing and data combination techniques in order to exploit the sensitivity improvement of the phased array coil acquisition method. This paper describes a novel method for the combination of MRS signals acquired by phased array coils, even in presence of correlated noise between the acquisition channels. In fact, although it has been shown that electric and magnetic coupling mechanisms produce correlated noise in the coils, previous algorithms developed for MRS data combination have ignored this effect. The proposed approach takes advantage of a noise decorrelation stage to maximize the SNR of the combined spectra. In particular Principal Component Analysis (PCA) was exploited to project the acquired spectra in a subspace where the noise vectors are orthogonal. In this subspace the SNR weighting method will provide the optimal overall SNR. Performance evaluation of the proposed method is carried out on simulated (1)H-MRS signals and experimental results are obtained on phantom (1)H-MR spectra using a commercially available 8-element phased array coil. Noise correlations between elements were generally low due to the optimal coil design, leading to a fair SNR gain (about 0.5%) in the center of the field of view (FOV). A greater SNR improvement was found in the peripheral FOV regions.

Doping graphene with metal contacts

Making devices with graphene necessarily involves making contacts with metals. We use density functional theory to study how graphene is doped by adsorption on metal substrates and find that weak bonding on Al, Ag, Cu, Au, and Pt, while preserving its unique electronic structure, can still shift the Fermi level with respect to the conical point by approximately 0.5 eV. At equilibrium separations, the crossover from p-type to n-type doping occurs for a metal work function of approximately 5.4 eV, a value much larger than the graphene work function of 4.5 eV. The numerical results for the Fermi level shift in graphene are described very well by a simple analytical model which characterizes the metal solely in terms of its work function, greatly extending their applicability.

A compatible electrocutaneous display for functional magnetic resonance imaging application

In this paper we propose an MR (magnetic resonance) compatible electrocutaneous stimulator able to inject an electric current, variable in amplitude and frequency, into the fingertips in order to elicit tactile skin receptors (mechanoreceptors). The desired goal is to evoke specific tactile sensations selectively stimulating skin receptors by means of an electric current in place of mechanical stimuli. The field of application ranges from functional magnetic resonance imaging (fMRI) tactile studies to augmented reality technology. The device here proposed is designed using safety criteria in order to comply with the threshold of voltage and current permitted by regulations. Moreover, MR safety and compatibility criteria were considered in order to perform experiments inside the MR scanner during an fMRI acquisition for functional brain activation analysis. Psychophysical laboratory tests are performed in order to define the different evoked tactile sensation. After verifying the device MR safety and compatibility on a phantom, a test on a human subject during fMRI acquisition is performed to visualize the brain areas activated by the simulated tactile sensation.

Graphite and graphene as perfect spin filters

Based upon the observations (i) that their in-plane lattice constants match almost perfectly and (ii) that their electronic structures overlap in reciprocal space for one spin direction only, we predict perfect spin filtering for interfaces between graphite and (111) fcc or (0001) hcp Ni or Co. The spin filtering is quite insensitive to roughness and disorder. The formation of a chemical bond between graphite and the open d-shell transition metals that might complicate or even prevent spin injection into a single graphene sheet can be simply prevented by dusting Ni or Co with one or a few monolayers of Cu while still preserving the ideal spin-injection property.

An electrodeless system for measurement of liquid sample dielectric properties in radio frequency band

An electrodeless measurement system based on a resonant circuit is proposed for the measurement of dielectric properties of liquid samples at RF (radio frequency). Generally, properties as dielectric constant, loss factor and conductivity are measured by parallel plate capacitor cells: this method has several limitations in the case of particular liquid samples and in the range of radiofrequencies. Our method is based on the measurements of resonance frequency and quality factor of a LC resonant circuit in different measuring conditions, without and with the liquid sample placed inside a test tube around which the home made coil is wrapped. The measurement is performed using a network analyzer and a dual loop probe, inductively coupled with the resonant circuit. One of the advantages of this method is the contactless between the liquid sample and the measurement electrodes. In this paper the measurement system is described and test measurements of conventional liquids dielectric properties are reported.

Expression of Fas and Fas ligand in human testicular germ cell tumours

In the present study, we analysed the expression of Fas ligand (FasL) and its cognate receptor Fas in 14 seminomatous testicular germ cell tumours (TGCT) and six normal testicular tissues obtained following orchiectomy. Tissue samples have been processed to prepare either total RNA or protein extracts or fixed and embedded in paraffin for immunohistochemistry (IHC) experiments. Quantitative RT-PCR experiments demonstrated in TGCT a significant (p < 0.01) increase of the FasL mRNA expression of 21.1 +/- 5.4 fold, with respect to normal tissues. On the contrary, in the same cancer tissues, the levels of Fas mRNA were significantly (p < 0.01) reduced to 0.27 +/- 0.06 fold. These observations were confirmed in western blot experiments showing a significant increase of FasL and a concomitant decrease of Fas proteins in testicular cancer tissues, with respect to normal testis. Moreover, IHC experiments showed a strong FasL immuno-reactivity in six out of eight TGCT samples analysed, while Fas immuno-positivity was found in cancer cells of only two TGCT tissues. In addition, in all tumour samples, infiltrating lymphocytes were Fas positive. However, no correlation could be observed between Fas or FasL mRNA variations and clinical parameters such as patient's age, TNM stage or tumour size. We also compared the serum levels of soluble FasL (sFasL) of 15 patients affected by seminomatous TGCT, of four patients with non-seminomatous TGCT and six age-matched healthy males. No significant differences in sFasL serum level could be identified. In conclusion, our data demonstrated that the majority of seminomas are characterized by an increased expression of FasL and a concomitant reduction of Fas, with respect to human normal testis, and that sFasL serum level is not a tumour marker for patients affected by TGCT.

Drug distribution and pharmacokinetic/pharmacodynamic relationship of paclitaxel and gemcitabine in patients with non-small-cell lung cancer

BACKGROUND

Gemcitabine and paclitaxel are two of the most active agents in non-small-cell lung cancer (NSCLC), and pharmacologic investigation of the combination regimens including these drugs may offer a valuable opportunity in treatment optimization. The present study investigates the pharmacokinetics and pharmacodynamics of paclitaxel and gemcitabine in chemotherapy-naive patients with advanced NSCLC within a phase I study.

PATIENTS AND METHODS

Patients were given i.v. paclitaxel 100 mg/m2 by one-hour infusion followed by gemcitabine 1,500, 1,750 and 2,000 mg/m2 by 30-min administration. Plasma levels of paclitaxel, gemcitabine and its metabolite 2',2'-difluorodeoxyuridine (dFdU) were determined by high-performance liquid chromatography (HPLC). Concentration-time curves were modeled by compartmental and non-compartmental methods and pharmacokinetic/pharmacodynamic (PK/PD) relationships were fitted according to a sigmoid maximum effect (Emax) model.

RESULTS

Paclitaxel pharmacokinetics did not change as a result of dosage escalation of gemcitabine from 1,500 to 2,000 mg/m2. A nonproportional increase in gemcitabine peak plasma levels (Cmax, from 18.56 +/- 4.94 to 40.85 +/- 14.85 microg/ml) and area under the plasma concentration-time curve (AUC, from 9.99 +/- 2.75 to 25.01 +/- 9.87 h x microg/ml) at 1,500 and 2,000 mg/m, respectively, was observed, suggesting the occurrence of saturation kinetics at higher doses. A significant relationship between neutropenia and time of paclitaxel plasma levels > or = 0.05 micromol/l was observed, with a predicted time of 10.4 h to decrease cell count by 50%. A correlation was also observed between percentage reduction of platelet count and gemcitabine Cmax, with a predicted effective concentration to induce a 50% decrease of 14.3 microg/ml.

CONCLUSION

This study demonstrates the lack of interaction between drugs, the nonproportional pharmacokinetics of gemcitabine at higher doses and the Emax relationship of paclitaxel and gemcitabine with neutrophil and platelet counts, respectively. In addition, gemcitabine 1,500 mg/m2 is the recommended dosage in combination with paclitaxel 100 mg/m2 for future phase II studies, due to its predictable kinetic behaviour and less severe thrombocytopenia than expected.