Metastatic cancer DNA phenotype identified in normal tissues surrounding metastasizing prostate carcinomas

Fourier transform-infrared statistical models have the proven ability to identify subtle structural changes in DNA at various stages of tumor development. Using these models, we show evidence for a metastatic cancer DNA phenotype in histologically normal prostate tissues surrounding metastasizing tumors. Strikingly, the DNA base and backbone structures of the metastatic phenotype are indistinguishable from those of the metastasizing prostate tumors but distinctly different from the structure recently reported for the primary cancer DNA phenotype. These findings suggest that the DNA structure linked to the development of metastasis is preordained in progenitor cells relatively early in multistep tumorigenesis. The substantial structural differences found between the primary and metastatic cancer DNA phenotypes suggest that each evolves through a separate pathway. The metastatic phenotype is potentially an early predictor of metastatic disease. Interventions that inhibit its formation would be expected to also inhibit the development of metastatic tumors.     

Effects of old age on vascular complexity and dispersion of the hepatic sinusoidal network

OBJECTIVES: In old age, there are marked changes in both the structure of the liver sinusoidal endothelial cell and liver perfusion. The objective of this study was to determine whether there are also aging changes in the microvascular architecture and vascular dispersion of the liver that might influence liver function. METHODS: Vascular corrosion casts and light micrographs of young (4 months) and old (24 months) rat livers were compared. Fractal and Fourier analyses and micro-computed tomography were used. Vascular dispersion was determined from the dispersion number for sucrose and 100-nm microspheres in impulse response experiments. RESULTS: Age did not affect sinusoidal dimensions, sinusoidal density, or dispersion number. There were changes in the geometry and complexity of the sinusoidal network as determined by fractal dimension and degree of anisotropy. CONCLUSIONS: There are small, age-related changes in the architecture of the liver sinusoidal network, which may influence hepatic function and reflect broader aging changes in the microcirculation. However, sinusoidal dimensions and hepatic vascular dispersion are not markedly influenced by old age.     

Comparison of the Eeg-Based Snap<Superscript>TM</Superscript> Index and the Bispectral (Bis<Superscript>TM</Superscript>) Index During Sevoflurane - Nitrous Oxide Anaesthesia

The BIS monitor (Aspect Medical Inc, Newton, USA) was the first electroencephalogram (EEG)-based monitor of the hypnotic effect reflected by a dimensionless figure ranging from 100 (awake state) to 0 (flat line EEG). Its widespread use makes it the most-studied and the best-known among same intended devices. Its algorithm processes low-frequency EEG oscillations in order to provide the Bispectral index. A BIS index ranging from 40 to 60 has been established as the proper for surgical performance. The BIS monitor permits a closer approach to the hypnotic component of anaesthesia beyond clinical signs and may reduce the probability of intraoperative awareness; therefore, it has become a recommended monitoring tool in routine practice. The SNAP^TM monitor (Nicolet Biomedical, Madison WI, USA) is also intended for monitoring the hypnotic effect of anaesthetics, which is in turn displayed as an index ranging from 100 to 0, with 100 meaning a fully awake state and 0 meaning no brain activity. The algorithm of the SNAP^TM monitor is featured by its additional processing of ultra-high EEG frequencies, which seem to be involved in the formation of consciousness. The use of these frequencies would theoretically improve responsiveness during increased brain activity. We studied its behaviour patterns and capability to monitor the hypnotic effect induced by sevoflurane-nitrous oxide by comparison with the BIS index. Seventy patients ASA I–III were induced with propofol, fentanyl and rocuronium, and maintained with sevoflurane-N₂O. BIS and SNAP indices were simultaneously recorded before induction, after intubation, after incision, at the following 10, 30 and 50 minutes, awakening and extubation time points, together with heart rate and blood pressure. The Pearson correlation was R² = 0.68 (p < .05). The Bland and Altman test showed a bias of 14.3 for SNAP index values with respect to BIS index values. We concluded that the SNAP index correlates with variations in the hypnotic effect induced by sevoflurane-nitrous oxide anaesthesia when compared with the BIS index. In this context, a SNAP index ranging from 58 to 70 would be equivalent to the BIS index range 40 to 60 and, therefore, the accurate for surgical performance. Preliminary results presented at the 13th World Congress of Anesthesiologists, Paris, France on April 17–23 and at Euroanaesthesia 2004, Lisbon, Portugal on June 5th–8th     

EEG abnormalities preceding the epilepsy onset in tuberous sclerosis complex patients – A prospective study of 5 patients

Tuberous sclerosis complex (TSC) is a multisystem, autosomal dominant disorder characterized by multiple hamartomas development. Epilepsy is the most common symptom appearing in 80–90% of the patients mainly in the first year of life. A prompt and early seizure control is crucial and can prevent development of an epileptic encephalopathy and secondary mental retardation. Therefore the very early identification of seizures seems to be of a great importance. We present the cases of 5 patients diagnosed with TSC prenatally or perinatally and regularly monitored (at 4–6 weeks intervals) with EEG before the epilepsy onset. The patients' age at baseline varied from 9 days to 9 weeks. In all of the patients epileptiform discharges preceded the epilepsy onset. The time interval between abnormality detection on EEG and the epilepsy onset varied from 1 to 8 days. The patient's age at the epilepsy onset ranged from the 17th day to the 5th month of life. In one patient the EEG was abnormal from the beginning and in this patient the epileptic seizures started from the neonatal period. In the rest of the patients (4/5) the EEG remained normal throughout the first months of life. In all of the children epilepsy started with focal motor seizures. Our study is the first prospective one showing the results of the EEG monitoring in TSC patients and the natural evolution of the EEG patterns in patients with the seizures types other than infantile spasms.     

局灶运动抑制性发作5例患儿临床特征及脑电图分析

目的 探讨局灶运动抑制性癫痫儿童的临床及电生理特点,提高对此类癫痫的认识.方法 回顾性分析2015年1月至2019年4月首都医科大学宣武医院儿科住院收治的5例有局灶运动抑制性癫痫患儿脑电图特点、临床特征和治疗情况.结果 5例患儿中男4例、女1例,起病年龄从2岁3月龄至9岁不等,5例均表现为一侧肢体无力,发作期间意识清楚...     

Brain activity in near-death experiencers during a meditative state

Aim

To measure brain activity in near-death experiencers during a meditative state.

Methods

In two separate experiments, brain activity was measured with functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) during a Meditation condition and a Control condition. In the Meditation condition, participants were asked to mentally visualize and emotionally connect with the “being of light” allegedly encountered during their “near-death experience”. In the Control condition, participants were instructed to mentally visualize the light emitted by a lamp.

Results

In the fMRI experiment, significant loci of activation were found during the Meditation condition (compared to the Control condition) in the right brainstem, right lateral orbitofrontal cortex, right medial prefrontal cortex, right superior parietal lobule, left superior occipital gyrus, left anterior temporal pole, left inferior temporal gyrus, left anterior insula, left parahippocampal gyrus and left substantia nigra. In the EEG experiment, electrode sites showed greater theta power in the Meditation condition relative to the Control condition at FP1, F7, F3, T5, P3, O1, FP2, F4, F8, P4, Fz, Cz and Pz. In addition, higher alpha power was detected at FP1, F7, T3 and FP2, whereas higher gamma power was found at FP2, F7, T4 and T5.

Conclusions

The results indicate that the meditative state was associated with marked hemodynamic and neuroelectric changes in brain regions known to be involved either in positive emotions, visual mental imagery, attention or spiritual experiences.     

Effects of alcohol on sleep and the sleep electroencephalogram in healthy young women

BACKGROUND: Although the association between sleep and alcohol has been of interest to scientists for decades, the effects of alcohol on sleep and sleep electroencephalogram (EEG) have not been extensively studied in women. Our specific aim was to determine whether sleep stage variables and/or spectral characteristics of the sleep EEG are altered by alcohol administration in women. METHODS: Changes of sleep and the sleep EEG were investigated after administration of a moderate dose of alcohol (0.49 g/kg) in the hour before bedtime compared with placebo in young healthy women. After approximately 2 weeks at home on a fixed 8.5- or 9-hour stabilization sleep schedule, sleep was continuously recorded by polysomnography for 3 consecutive nights [adaptation, placebo, alcohol (mean breath alcohol concentration 0.043 g/% before bedtime)] in the laboratory in 7 women (ages 22-25, mean=23.5, SD=1 year). Sleep stages were scored according to conventional criteria. Electroencephalogram power spectra of the bipolar derivations Fz/Cz (anterior) and Pz/Oz (posterior) were calculated using a fast Fourier transform routine. RESULTS: Only few changes in sleep and the sleep EEG were observed. Across the entire night rapid eye movement (REM) sleep decreased, while minutes of stage 4 sleep were increased in the first 2-hour interval on alcohol nights compared with placebo nights. Spectral analysis of the EEG showed increased power in the alpha range (9-11 Hz) during all-night non-REM (NREM) sleep in anterior derivations after alcohol compared with placebo. Differences in spectral EEG power were also present in 2-hour intervals of NREM sleep; in particular, EEG power was increased on the alcohol night for frequency bins within the alpha range in anterior derivations and within the delta range (3-4 Hz) in posterior derivations during the initial part of the night. CONCLUSIONS: A moderate dose of alcohol just before bedtime resulted in a short-lived increase in sleep intensity. A limitation of the study, however, was that only a single dose of alcohol was used to examine the effects of alcohol on sleep.