Brain Networks Modulation during Simple and Complex Gait: A "Mobile Brain/Body Imaging" Study

Walking encompasses a complex interplay of neuromuscular coordination and cognitive processes. Disruptions in gait can impact personal independence and quality of life, especially among the elderly and neurodegenerative patients. While traditional biomechanical analyses and neuroimaging techniques have contributed to understanding gait control, they often lack the temporal resolution needed for rapid neural dynamics. This study employs a mobile brain/body imaging (MoBI) platform with high-density electroencephalography (hd-EEG) to explore event-related desynchronization and synchronization (ERD/ERS) during overground walking. Simultaneous to hdEEG, we recorded gait spatiotemporal parameters. Participants were asked to walk under usual walking and dual-task walking conditions. For data analysis, we extracted ERD/ERS in α, β, and γ bands from 17 selected regions of interest encompassing not only the sensorimotor cerebral network but also the cognitive and affective networks. A correlation analysis was performed between gait parameters and ERD/ERS intensities in different networks in the different phases of gait. Results showed that ERD/ERS modulations across gait phases in the α and β bands extended beyond the sensorimotor network, over the cognitive and limbic networks, and were more prominent in all networks during dual tasks with respect to usual walking. Correlation analyses showed that a stronger α ERS in the initial double-support phases correlates with shorter step length, emphasizing the role of attention in motor control. Additionally, β ERD/ERS in affective and cognitive networks during dual-task walking correlated with dual-task gait performance, suggesting compensatory mechanisms in complex tasks. This study advances our understanding of neural dynamics during overground walking, emphasizing the multidimensional nature of gait control involving cognitive and affective networks.

The impact of cognitive function deficits and their recovery on functional outcome in subjects affected by ischemic subacute stroke: results from the Italian multicenter longitudinal study CogniReMo

BACKGROUND

The recovery of independence in activities of daily living is a fundamental goal of rehabilitation programs in subjects affected by subacute stroke. Rehabilitation is focused both on motor and cognitive aspects, and some evidence has reported cognitive deficits as prognostic factors of motor recovery. However, rehabilitation is a dynamic process during which executive functions and motor functions should be improved.

AIM

The aim of the study is to evaluate the relationships between impairments in cognitive functions and recovery of functional independence in stroke patients during the subacute phase.

DESIGN

Multicenter observational study.

SETTING

Intensive rehabilitation units.

POPULATION

A sample of 319 stroke patients in subacute phase (70.6±11.6 years, 40.4% females), consecutively admitted from November 2019 to July 2021 at sixteen rehabilitation centers were enrolled in this observational, prospective and multicentric study with longitudinal assessments.

METHODS

Cognitive and functional assessments were performed at hospital admission and discharge, including Oxford Cognitive Screen, modified Barthel Index, Functional Independent Measure, Fugl-Meyer assessment scale and National Institutes of Health Stroke Scale.

RESULTS

A regression analysis identified five predictors (out of about 200 tested variables) of functional recovery related to four aspects assessed at admission: functional status (P<0.001), lower limb functioning (P=0.002), attention (P=0.011), and executive functions (P=0.017). Furthermore, patients who recovered deficits in executive functions had the same recovery of those without deficits, whereas those who maintained deficits had a smaller recovery (P=0.019).

CONCLUSIONS

The relationship between cognitive and motor deficits is increasingly highlighted and the recovery of executive functions deficits seems to contribute to motor recovery.

CLINICAL REHABILITATION IMPACT

Our results suggest that the recovery of executive functions may promote the recovery of the functional outcome of the patient with subacute stroke. Future treatment protocols may benefit from paying more attention to the recovery of executive functions.

Do not forget the lungs: I/E mode physiotherapy for people recovering from COVID-19. Preliminary feasibility study

BACKGROUND

Early chest physiotherapy is recommended for patients with post-COVID syndrome to improve dyspnea, relieve anxiety, minimize disability, preserve lung function and improve quality of life. However, there is still no consensus on the best treatments to manage respiratory symptoms. We aimed to test a method based on a guided in/expiratory (I/E) modulation to treat the lung inhomogeneity.

METHODS

Twenty patients with post-COVID syndrome and mild-to-moderate obstructive syndrome performed 3 15-min sessions/day using the I/E mode of the T-PEP®4 device, for 15 consecutive days. Lung function parameters, dyspnea and quality of life scores, as well as exercise capacity were assessed before and after treatment.

RESULTS

All patients concluded the treatment and showed significant improvements in symptoms (chest pain during deep inspiration, chest tightness, inability to yawn, fatigue during activities of daily living [ADL], desaturation ≥4% during ADL) and in health status (BCSS -1.75, p=0.0003; CAT -5.2, p=0.0001). Lung function (FVC +10.9%, p=0.0002; FEV1 +8%, p=0.0001) and respiratory muscle strength (MIP +13.8%, p<0.0001; SNIP +13.6%, p=0.0122; MEP +7.6%, p=0.0045) improved. Exercise capacity also improved (6MWT +14.2%, p=0.005). At the end of treatment, only 2 patients reported symptoms and ADL-induced desaturation, while 14 still had fatigue during ADL.

CONCLUSIONS

This study shows that chest physiotherapy using an I/E device to actively recruit peripheral lungs in COVID-19 patients early after hospital discharge improved lung function tests as well as respiratory muscle strength, exercise capacity and quality of life.

Swallowing dysfunctions in Parkinson’s disease patients: a novel challenge for the internist

Parkinson’s disease (PD) is a chronic neurodegenerative disorder with a typical movement pattern, as well as different, less studied non-motor symptoms such as dysphagia. Disease-related disorders in efficacy or safety in the process of swallowing usually lead to malnutrition, dehydration or pneumonia. Dysphagia and subsequent aspiration pneumonia are common causes of morbidity and mortality in those with PD. The aim of this review is to identify and evaluate the existing literature on swallowing disorders in PD and providing recommendations for clinical practice routine.

[Carcinomatous meningitis. Presentation of 3 cases]

Meningeal carcinomatosis is characterized by diffuse infiltration of the leptomeninges by metastatic cancer in patients usually with a previous history of malignancy. Primary tumors are adenocarcinomas of the breast or lung, or malignant melanoma. The clinical presentation is pleomorphic and commonly affects the cerebral hemispheres, the cranial nerves, or spinal cord and its roots. Diagnosis is confirmed by the presence of the malignant cells in the cerebrospinal fluid (CSF). Computed tomography (CT) and magnetic resonance (MRI) show abnormal findings including ventricular dilatation and small enhancing lesions along the CSF space. Despite radiotherapy and chemotherapy, vital prognosis remains bad and the treatment is useful in improving the quality of life. Three cases presented here emphasize once again the important fact that meningeal carcinomatosis remains a very difficult diagnosis; several lumbar punctures were sometimes necessary, and cerebral fluid studies cannot yet be replaced by other diagnostic techniques like contrast enhanced CT or MRI with gadolinium.

[Interaction between schooling and physiognomic recognition: neuropsychological study in a group of patients with unilateral brain lesions]

Groups of left-hemisphere damaged patients, right-hemisphere damaged patients and controls were given the facial recognition test of Benton and Van Allen. Educational level was found to be relevant with regard to the performance of the brain damaged groups, such that a difference between left and right hemisphere-damaged groups became apparent only in patients with higher (greater than 5 years) schooling. The implications of the results are discussed.

Conformational effects on the activity of drugs. 10. Synthesis, conformation, and pharmacological properties of 1-(2,5-dimethoxyphenyl)-2-aminoethanols and their morpholine analogues

In order to obtain a better understanding of the effects that structural parameters have on the changes of adrenergic activity when 1-aryl-2-aminoethanol derivatives are converted into their corresponding 2-arylmorpholine cyclic analogues, we synthesized 1-(2,5-dimethoxyphenyl)-2-aminoethanol derivatives 5-7 and their morpholine analogues 8-10. The preferred conformation of amino alcohols and their cyclic analogues have been determined through an H NMR and IR study. Compounds 5 and 6 showed both alpha-stimulating and alpha-blocking activity on rat vas deferens, the effect depending on the concentration employed; on the same isolated tissue, N-isopropyl derivative 7 and the morpholine analogues 8-10 exhibited only alpha-blocking activity. As for the beta-adrenergic activity, only the open-chain compound 7 possessed a moderate blocking effect on isolated guinea pig atria. The results of this work seem to indicate that the changes of pharmacological activity involved in the transformation of the adrenergic drugs into their morpholine analogues are influenced more by characteristic features of the aromatic moiety than by the ethanolamine or propanolamine structure of the drugs.

Toxicity of some essential plant oils. Clinical and experimental study

Commercial preparations of essences of sage, hyssop, thuja, and cedar have caused human intoxication in eight cases, from which tonico-clonic convulsions were the major symptom. The experimental study of the toxic properties of commercialized essential oils of sage and hyssop has revealed that their convulsant action was of central nervous system origin in unanesthetized rats, as proven by electrocortical records. The toxicity of the hyssop oil seems to be more powerful than that of sage, since the dose limit from which the cortical events are only subclinical is 0.08 g/kg for hyssop oil and 0.3 g/kg for sage oil. Above 0.13 g/kg for hyssop oil and 0.50 g/kg for sage oil, the convulsions appeared and became lethal above 1.25 g/kg with hyssop oil and 3.2 g/kg with sage oil. The daily repeated injection of subclinical doses revealed the cumulative toxic effect of hyssop oil, since the same low dose induced electrocortical clonic seizures. The toxicity of each oil appeared to be related to the presence of terpenic ketones, camphor in sage commercial oil, camphor and thujone in sage Dalmatian oil, thujone in thuja and cedar oils, and pinocamphone in hyssop oil. The convulsant properties of camphor are well known. The neurotoxicity of thujone and pinocamphone is demonstrated in rats for the first time.

Effect of pyridoxine, glyoxylic acid and pyridoxylate on oxidative metabolism in vitro and phosphorylated energy-rich compounds studied in rat brains during acute hypoxia and ischaemia

Pyridoxine (1-8 mmol/l) did not change significantly the cerebral oxygen nor the hypoxic or ischaemic degradation of phosphocreatine and ATP. Glyoxylic acid (1-8 mmol/l), an inhibitor of the citric acid cycle, depressed the electrically stimulated oxygen uptake of brain slices to a lesser extent than did pyridoxylate. Moreover, at concentrations of 0.66 mmol/l, pyridoxylate predominantly delayed the hypoxic or the ischaemic breakdown of creatine phosphate and of ATP compared with glyoxylic acid (0.66 mmol/l). These findings paralleled clearly the prominent hypoxic and post-hypoxic protection afforded by pyridoxylate upon rat brain electrogenesis, reported in the preceding paper.

Electroencephalographic protective action of pyridoxylate during acute hypoxia and subsequent recovery in the rat

Pyridoxylase at a concentration of 0.6 mmol/kg body weight injected intraperitoneally in rats, increased the resistance of animals to severe hypoxia (O2:3.2%; N2; 96.,%). The electrocorticogram (ECoG) was used to indicate the effectiveness of the drug in lowering the delay of electrographic silence, in 19 control rats and 12 pretreated rats. The ECoG was also recorded period under pure oxygen. In pretreated rats, the ECoG records became flat in a mean time of 551 s, compared with 269 s in the control group. The latent periods of successive steps during cerebral anoxia were significantly delayed in pyridoxylate-pretreated rats subjected to hypoxia. During the recovery period, pyridoxylate improved the recovery of the normal ECoG, particularly when values were expressed as a function of the duration of the hypoxic period. These findings are in good agreement with the significant protection afforded by pyridoxylate on the cerebral rate of energy-rich phosphate bond utilization during hypoxia studied in a separate work.

[Experimental study of the toxic convulsant properties of commercial preparations of essences of sage and hyssop (author's transl)]

Commercial preparations of essences of sage and hyssop have caused poisoning of human beings and were found to possess a convulsant action of central origin in animals. The convulsant effect of hyssop essence appears to be more powerful than that of sage in non-anaesthetized rats. The dose limit, below which the cortical phenomena are subclinical, is 0.08 g/kg for hyssop, while above 0.13 g/kg convulsions appear and become lethal above 1.25 g/kg. The same doses for essence of sage are respectively 0.3, 0.5 and 3.2 g/kg. The neurotoxicity of hyssop appears to be related to the presence of two terpene ketones, pinocamphone and isopinocamphone, the former of which has powerful convulsant properties, and is lethal at doses above 0.05 ml/kg. The toxicity of essence of sage is due to the presence of camphor which is well-known to possess convulsant properties.

[Effect of chlorimipramine on the so-called ponto-geniculo-occipitalactivity (PGO) in a primate, Papio hamadryas (author's transl)]

Three hamadryas adult baboons (female) received 24 daily injections of Chlorimipramine (1.7 mg/kg). The effects on sleep were nearly identical with the effects observed in man. PGO activity, recorded in the lateral geniculate nucleus, was much disturbed. The total number of PGO fell downward from the first recording. The number of PGO/min during paradoxial sleep was even more decreased. This fact suggests a selective influence of CL I on the mechanisms of PGO activity. Is the particular effect of importance to the treatment of depression symptoms?