Double Pathology in Rasmussen Encephalitis.

Investigators from Children's Hospital Colorado and University of Colorado conducted a retrospective review of electronic medical records to identify all Rasmussen Encephalitis (RE) cases that had undergone surgery with subsequent pathologic evaluation at Children's Hospital Colorado during 2005-2019 to determine the frequency of double pathology.

Cell cycle-targeting microRNAs promote differentiation by enforcing cell-cycle exit.

MicroRNAs (miRNAs) have been known to affect various biological processes by repressing expression of specific genes. Here we describe an essential function of the miR-34/449 family during differentiation of epithelial cells. We found that miR-34/449 suppresses the cell-cycle machinery in vivo and promotes cell-cycle exit, thereby allowing epithelial cell differentiation. Constitutive ablation of all six members of this miRNA family causes derepression of multiple cell cycle-promoting proteins, thereby preventing epithelial cells from exiting the cell cycle and entering a quiescent state. As a result, formation of motile multicilia is strongly inhibited in several tissues such as the respiratory epithelium and the fallopian tube. Consequently, mice lacking miR-34/449 display infertility as well as severe chronic airway disease leading to postnatal death. These results demonstrate that miRNA-mediated repression of the cell cycle is required to allow epithelial cell differentiation.

Impairment of gastrointestinal motility by nitrate administration: evaluation based on electrogastrographic changes and autonomic nerve activity.

BACKGROUND: Nitrates decrease the tone of the lower oesophageal sphincter, and may thus induce gastro-oesophageal reflux. AIM: In the present study, we evaluated electrogastrographic changes and heart-rate variability before and after the administration of nitrates. METHODS: In 15 patients with chest pain treated with nitrates, electrocardiography and percutaneous electrogastrography were performed before and after administration of nitrates. Autonomic nervous system function was evaluated by spectral analysis of heart-rate variability and serial changes in low frequency and high frequency power, and the low frequency/high frequency ratio were compared. Electrogastrograms were analysed by obtaining peak power amplitudes and their dominant frequencies. RESULTS: After the administration of nitrates (isosorbide dinitrate), high frequency power, an index of parasympathetic nervous activity, was significantly decreased, whereas the low frequency/high frequency ratio, an index of sympathetic nervous activity, was significantly increased. The mean peak amplitude of the electrogastrogram significantly increased postprandially both before and after treatment. After isosorbide dinitrate treatment, however, mean peak amplitudes after a meal were significantly lower than those obtained before treatment. The mean dominant frequency of the electrogastrogram did not vary before and after treatment. CONCLUSIONS: The present study suggests that nitrates inhibit gastrointestinal motility by decreasing autonomic nervous activity.

Autonomic nervous activity before and after eradication of Helicobacter pylori in patients with chronic duodenal ulcer.

BACKGROUND: Helicobacter pylori infection is involved in the formation of chronic peptic ulcer. However, a previously reported hypothesis concerning the involvement of central autonomic nervous disorder in this condition cannot be ruled out. AIM: To use spectrum analysis of heart rate viability to examine autonomic nervous activity before and after H. pylori eradication. METHODS: Twenty patients with chronic duodenal ulcer (duodenal ulcer group) and 20 age-matched normal adults (N group). In both groups, 24-h Holter electrocardiograms (ECGs) were recorded and spectrum analysis of heartrate variability was performed. In the duodenal ulcer group, Holter ECG was recorded before and after H. pylori eradication. RESULTS: In the N group, analysis of heart rate variability showed that high frequency (HF) power, an index of parasympathetic activity, was high at night, while the low frequency (LF)/HF ratio, an index of sympathetic function, was high during the daytime. In the duodenal ulcer group, HF power was higher at night than during the daytime, showing a similar pattern to the N group, but the power value was higher than in the N group (P < 0.05). In the duodenal ulcer group, LF/HF at night was significantly higher than that of the N group. In addition, in the duodenal ulcer group, autonomic activity after H. pylori eradication did not differ significantly from that before H. pylori eradication. CONCLUSIONS: In patients with chronic peptic ulcer, both sympatheticotonia and parasympatheticotonia may occur at night, and this abnormality in autonomic nervous activity may cause increased gastric acid secretion and gastric mucosal vasoconstriction. Abnormalities in autonomic activity persist even after H. pylori eradication, suggesting that they may be an independent risk factor in the formation of chronic peptic ulcer in addition to H. pylori infection.

Autonomic nervous function in patients with peptic ulcer studied by spectral analysis of heart rate variability.

This study is intended to clarify the relationship between occurrence of peptic ulcer disease and dysfunction of the autonomic nervous system. We studied heart rate variability and assessed the circadian rhythm of autonomic nervous function in 20 patients with peptic ulcer (PU group) and 20 age-matched healthy controls (N group) using 24-hour Holter monitoring. Moreover, the relationship between gastric juice secretion and autonomic activity was examined under intravenous injection of insulin or butylscopolamine in adult mongrel dogs. High frequency spectral (HF) power, an indicator of parasympathetic tone, was increased markedly at night in the PU group. Low frequency spectral (LF) power, an indicator of sympathetic tone modified by vagal tone, was higher during the day than at night in the N group, whereas this normal circadian rhythm of LF power disappeared in 11 cases (55%) in the PU group. In addition, the LF power was increased significantly at night (p<0.01) in the PU group. HF power and gastric juice secretion was increased by the administration of insulin. High sympatho-vagal tone at night may result in spasm of gastric arteries and excess secretion of gastric acid in the PU group. These results suggest that the nocturnal acceleration of LF, HF, and LF/HF is related to peptic ulcer diseases.

Derivative chromosome 17 in a case of Burkitt lymphoma with 8;14 translocation.

A complex chromosome rearrangement present in a B-cell line established from a patient with Burkitt lymphoma was studied by using fluorescence in situ hybridization (FISH) and immunocytochemistry techniques. The rearranged chromosome (der17) was apparently composed of 17q, of a partially deleted 17p, and of other material of chromosome 17p origin that was interspersed with regions without any clear banding pattern. der(17) contained a functional ch17 centromere and two additional centromeres of unknown origin that were inactive by all evidence. By FISH analysis with a TP53 probe, a signal could be demonstrated on the normal ch17, but not on the rearranged chromosome, a finding which indicates that 17p deletion caused a concurrent loss of one of the two TP53 alleles. The marker chromosome was previously observed in some of the malignant cells obtained from the patient's peripheral blood. These observations therefore indicate that cells with this specific rearrangement were generated in vivo and subsequently selected. This rearrangement is likely to have conferred a selective growth advantage to a subclone present in the original malignant cell population.