A subcortical oscillatory network contributes to recovery of hand dexterity after spinal cord injury

Recent studies have shown that after partial spinal-cord lesion at the mid-cervical segment, the remaining pathways compensate for restoring finger dexterity; however, how they control hand/arm muscles has remained unclear. To elucidate the changes in dynamic properties of neural circuits connecting the motor cortex and hand/arm muscles, we investigated the cortico- and inter-muscular couplings of activities throughout the recovery period after the spinal-cord lesion. Activities of antagonist muscle pairs showed co-activation and oscillated coherently at frequencies of 30–46 Hz (γ-band) by 1-month post-lesion. Such γ-band inter-muscular coupling was not observed pre-lesion, but emerged and was strengthened and distributed over a wide range of hand/arm muscles along with the recovery. Neither the β-band (14–30 Hz) cortico-muscular coupling observed pre-lesion nor a γ-band oscillation was observed in the motor cortex post-lesion. We propose that a subcortical oscillator commonly recruits hand/arm muscles, via remaining pathways such as reticulospinal and/or propriospinal tracts, independent of cortical oscillation, and contributes to functional recovery

Neural Substrates for the Motivational Regulation of Motor Recovery after Spinal-Cord Injury

It is believed that depression impedes and motivation enhances functional recovery after neuronal damage such as spinal-cord injury and stroke. However, the neuronal substrate underlying such psychological effects on functional recovery remains unclear. A longitudinal study of brain activation in the non-human primate model of partial spinal-cord injury using positron emission tomography (PET) revealed a contribution of the primary motor cortex (M1) to the recovery of finger dexterity through the rehabilitative training. Here, we show that activity of the ventral striatum, including the nucleus accumbens (NAc), which plays a critical role in processing of motivation, increased and its functional connectivity with M1 emerged and was progressively strengthened during the recovery. In addition, functional connectivities among M1, the ventral striatum and other structures belonging to neural circuits for processing motivation, such as the orbitofrontal cortex, anterior cingulate cortex and pedunculopontine tegmental nucleus were also strengthened during the recovery. These results give clues to the neuronal substrate for motivational regulation of motor learning required for functional recovery after spinal-cord injury

Efficacy of multimodal treatment for leptomeningeal metastases in a lung cancer harboring an EGFR mutation

Daisuke Morichika,1 Toshio Kubo,2 Hiroko Gotoda,1 Tomoki Tamura,1 Kadoaki Ohashi,1 Katsuyuki Hotta,1 Masahiro Tabata,2 Kazuhiko Kurozumi,3 Mitsune Tanimoto,4 Katsuyuki Kiura1 1Department of Respiratory Medicine, 2Center for Clinical Oncology, Okayama University Hospital, Okayama, Japan; 3Department of Neurological Surgery, 4Department of Hematology, Oncology, and Respiratory Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan Abstract: For lung cancer patients with epidermal growth factor receptor (EGFR) mutations, the advent of EGFR tyrosine kinase inhibitors (TKIs) has prolonged survival rates. Even though disease sites have been well controlled by EGFR-TKIs, some patients develop carcinomatous meningitis, which reduces their quality of life drastically. Although multidisciplinary approaches have improved patient survival and quality of life, the outcomes are not yet satisfactory. We report the case of a 54-year-old Japanese woman diagnosed with leptomeningeal metastases (LM) from a lung adenocarcinoma harboring an EGFR exon 21 L858R point mutation. She was treated with gefitinib for 2 months, and symptoms of LM emerged during the treatment period. Although the treatment was switched to erlotinib, disturbance of consciousness worsened because of progressive hydrocephalus. Because all extracranial lesions remained responsive to treatment, and the exon 20 T790M point mutation was not detected in cerebrospinal fluid, we placed a ventriculoperitoneal shunt. The patient’s disturbed consciousness improved dramatically after the shunt was placed; however, the optic and auditory nerve impairments due to direct invasion of LM lesions into nerve canals persisted. Administration of bevacizumab subsequent to whole-brain radiotherapy reduced the cranial nerve impairment, and the patient survived for 10 months. In conclusion, a combination of erlotinib and ventriculoperitoneal shunt was effective for hydrocephalus, and the immediate administration of additional therapies, including bevacizumab and radiation therapy, was useful in a patient suffering from LM. Keywords: bevacizumab, erlotinib, ventriculoperitoneal shunt, leptomeningeal metastases, lung cancer, EGF

An autopsy case of right ventricular cardiac metastasis from squamous cell carcinoma of the left hand

We here report a 60-year-old woman in whom autopsy revealed a metastasis in the right cardiac ventricle from a well-differentiated squamous cell carcinoma (SCC) of the left hand. The tumors in the myocardium and left hand were both well-differentiated SCCs with keratinization and sporadic keratin pearls. High concentrations of heart failure markers together with a pericardial effusion suggested antemortem chronic heart failure. Our case is particularly unusual because there were no regional lymph node metastases and the cardiac metastasis was not one of multiple metastases; thus, hematogenous metastasis to the right side of the heart alone had occurred