Beyond broadband: Towards a spectral decomposition of electroencephalography microstates

Originally applied to alpha oscillations in the 1970s, microstate (MS) analysis has since been used to decompose mainly broadband electroencephalogram (EEG) signals (e.g., 1–40 Hz). We hypothesised that MS decomposition within separate, narrow frequency bands could provide more fine‐grained information for capturing the spatio‐temporal complexity of multichannel EEG. In this study, using a large open‐access dataset (n = 203), we first filtered EEG recordings into four classical frequency bands (delta, theta, alpha and beta) and thereafter compared their individual MS segmentations using mutual information as well as traditional MS measures (e.g., mean duration and time coverage). Firstly, we confirmed that MS topographies were spatially equivalent across all frequencies, matching the canonical broadband maps (A, B, C, D and C′). Interestingly, however, we observed strong informational independence of MS temporal sequences between spectral bands, together with significant divergence in traditional MS measures. For example, relative to broadband, alpha/beta band dynamics displayed greater time coverage of maps A and B, while map D was more prevalent in delta/theta bands. Moreover, using a frequency‐specific MS taxonomy (e.g., ϴA and αC), we were able to predict the eyes‐open versus eyes‐closed behavioural state significantly better using alpha‐band MS features compared with broadband ones (80 vs. 73% accuracy). Overall, our findings demonstrate the value and validity of spectrally specific MS analyses, which may prove useful for identifying new neural mechanisms in fundamental research and/or for biomarker discovery in clinical populations.     

Baixa Concordância entre a Classificação da NYHA e as Variáveis do Teste de Exercício Cardiopulmonar em Pacientes com Insuficiência Cardíaca e Fração de Ejeção Reduzida

BackgroundThe New York Heart Association (NYHA) functional classification is the most commonly used classification system for heart failure (HF), whereas cardiopulmonary exercise testing (CPET) is the gold standard for functional status evaluation in HF.ObjectiveThis study aimed to analyze correlation and concordance between NYHA classes and CPET variables.MethodsHF patients with clinical indication for CPET and ejection fraction (EF) < 50% were selected. Correlation (Spearman coefficient) and concordance (kappa) between NYHA classification and CPET-based classifications were analyzed. A p < 0.05 was accepted as significant.ResultsIn total, 244 patients were included. Mean age was 56 ± 14 years, and mean EF was 35.5% ± 10%. Distribution of patients according to NYHA classification was 31.2%% class I, 48.3% class II, 19.2% class III, and 1.3% class IV. Correlation (r) between NYHA and Weber classes was 0.489 (p < 0.001), and concordance was 0.231 (p < 0.001). Correlation (r) between NYHA and ventilatory classes (minute ventilation/carbon dioxide production [VE/VCO₂] slope) was 0.218 (p < 0.001), and concordance was 0.002 (p = 0.959). Spearman correlation between NYHA and CPET score classes was 0.223 (p = 0.004), and kappa concordance was 0.027 (p = 0.606).ConclusionThere was a moderate association between NYHA and Weber classes, although concordance was low. Ventilatory (VE/VCO₂slope) and CPET score classes had a weak association and a low concordance with NYHA classes.     

Laparoscopic hiatal hernia repair in patients with poor esophageal motility or paraesophageal herniation

Laparoscopic repair for gastroesophageal reflux disease is now an accepted therapy. However, controversy exists with regard to the choice of operation between complete 360-degree Nissen fundoplication versus partial 270-degree Toupe fundoplication. In addition there is some controversy with regard to the proper choice of operation in patients with poor esophageal motility. Another class of hiatal hernia patients are those patients with paraesophageal herniation. Questions regarding the approach to these patients include whether or not to use a reflux procedure at the time of repair and the role of mesh in repair of these large hernias. This retrospective study was undertaken to compare the results of laparoscopic Nissen fundoplication and Toupe fundoplication in patients with both normal and abnormal esophageal motility. In addition the subset of patients with paraesophageal herniation was studied in an effort to ascertain the best surgical approach in these patients. In this study a retrospective analysis was performed on 188 consecutive patients during the period 1995 to 2001. All patients who presented with hiatal hernia surgical problems during this period were included. Endoscopy was performed in all patients with esophageal reflux. Manometry was performed in all patients except those presenting as emergency incarcerations. pH probe testing was performed in those patients in whom it was deemed necessary to establish the diagnosis. Upper gastrointestinal radiographs were used to define anatomy in paraesophageal hernia patients when possible. All patients with esophageal reflux were first treated with a trial of medical therapy. Patients with esophageal reflux and normal esophageal motility underwent 360-degree Nissen fundoplication. Those patients with poor esophageal motility (less than 65 mm of mercury) underwent laparoscopic 270-degree Toupe fundoplication. Patients presenting with paraesophageal herniation underwent laparoscopic repair. When possible esophageal manometry was performed on these patients preoperatively and if normal peristalsis was documented a Nissen fundoplication was performed. If poor esophageal motility was documented before surgery a Toupe fundoplication was performed. Mesh reinforcement of the diaphragmatic hiatus was used if necessary to complete a repair without tension. Patients were followed both by their primary gastroenterologist and their surgeon. Follow-up studies including endoscopy, pH probe, and upper gastrointestinal series were used as necessary in the postoperative period to document any problems as they occurred. Of the 188 patients in the study 141 patients underwent Nissen fundoplication, 21 patients underwent Nissen fundoplication and repair of paraesophageal hernia, 15 underwent Toupe fundoplication, seven underwent Toupe and paraesophageal hernia repair, and four paraesophageal hernia repair alone. One hundred eighty-three patients underwent a laparoscopic operation. Five patients of the 188 underwent an initial open operation-two of these patients because of the size of their paraesophageal hernia. Three of these patients had reoperations of remote operations done years before at other institutions. Twenty-two patients with poor esophageal motility (11.7 %) were included in the study. Fifteen patients required Toupe fundoplication whereas seven patients required Toupe fundoplication and repair of paraesophageal hernias. Mesh repair of paraesophageal hernias was accomplished in ten patients. Patients undergoing Toupe fundoplication had a 13 per cent dysphagia rate less than 4 weeks postoperatively and a 0% dysphagia rate greater than four weeks postoperatively. Patients undergoing Nissen fundoplication had a 16 per cent dysphagia rate less than 4 weeks postoperatively, 2 per cent dysphagia rate greater than 4 weeks postoperatively and no dysphagia at 6 weeks postoperatively. Recurrent symptomatic reflux occurred in 1.4 per cent of Nissen fundoplications and 6.7 per cent of Toupe fundoplications. Of Nissen and paraesophageal repairs 14.2 per cent had reflux and 14.3 per cent of Toupe and paraesophageal repairs had recurrent symptomatic reflux. Overall, complication rate was low. Use of mesh to repair large paraesophageal hernias resulted in a recurrence rate of 0 per cent. There was no instance of infection or bowel fistulization related to the use of mesh. We conclude that laparoscopic Nissen fundoplication in patients with normal esophageal motility is associated with a low rate of dysphagia and a low rate of recurrent reflux. Toupe fundoplication when used in reflux patients with poor esophageal motility is associated with a low rate of dysphagia and an acceptable rate of recurrent reflux. Laparoscop     

The role of osmic acid in the treatment of immune synovitis

Thirty-seven New Zealand rabbits were observed for up to 1 year after their knee joints were instilled with 1 ml of 1% osmic acid. A selective destruction of synovial lining cells occurred with a concurrent synovitis, but lining cell regenerated by the eighth week. Nonprogressive abnormalities were also present in the cartilage. When an immune synovitis was induced in both knees of 16 rabbits, the osmic acid treated joint demonstrated a significantly greater synovitis and progressive aberrations compared to the untreated knee.     

Targeting JNK-interacting protein 1 (JIP1) sensitises osteosarcoma to doxorubicin

Osteosarcoma (OS) is the most common primary malignant bone tumour in children and adolescents. Despite aggressive therapy, survival outcomes remain unsatisfactory, especially for patients with metastatic disease or patients with a poor chemotherapy response. Chemoresistance contributes to treatment failure. To increase the efficacy of conventional chemotherapy, essential survival pathways should be targeted concomitantly. Here, we performed a loss-of-function siRNA screen of the human kinome in SaOS-2 cells to identify critical survival kinases after doxorubicin treatment. Gene silencing of JNK-interacting-protein-1 (JIP1) elicited the most potent sensitisation to doxorubicin. This candidate was further explored as potential target for chemosensitisation in OS. A panel of OS cell lines and human primary osteoblasts was examined for sensitisation to doxorubicin using small molecule JIP1-inhibitor BI-78D3. JIP1 expression and JIP1-inhibitor effects on JNK-signalling were investigated by Western blot analysis. JIP1 expression in human OS tumours was assessed by immunohistochemistry on tissue micro arrays. BI-78D3 blocked JNK-signalling and sensitised three out of four tested OS cell lines, but not healthy osteoblasts, to treatment with doxorubicin. Combination treatment increased the induction of apoptosis. JIP1 was found to be expressed in two-thirds of human primary OS tissue samples. Patients with JIP1 positive tumours showed a trend to inferior overall survival. Collectively, JIP1 appears a clinically relevant novel target in OS to enhance the efficacy of doxorubicin treatment by means of RNA interference or pharmacological inhibition.