This study investigated the pharmacodynamic effects and sedative potential of midazolam administered by the intranasal route to adult volunteers. A double-blind, randomized, controlled study was carried out on seventeen healthy, male volunteers to study plasma level changes, sedative effects and variations in vital signs following intranasal administration of 0.2 mg/kg and 0.3 mg/kg doses of midazolam. Eight subjects received 0.2 mg/kg midazolam, seven received 0.3 mg/kg. Each subject rested for 15-20 minutes after placement of vital sign monitors and venipuncture needles before administration of midazolam. Behavior during the rest period was designated as the control so that each subject acted as his own control. Each subject's behavior was assessed on a scale of 1 (asleep) to 8 (excited). Plasma concentrations of midazolam were analyzed using venous blood samples from each of three randomly selected subjects for each of the two doses. Vital signs, monitored continuously, included electrocardiogram, heart rate, blood pressure, respiratory rate and oxygen saturation (SPO2). Plasma concentration of midazolam in both groups maintained adequate sedation levels with each group sustaining favorable sedation conditions from 15-20 minutes to 55-60 minutes. Individual variations of midazolam plasma concentration within the 0.3 mg/kg group were greater than those of the 0.2 mg/kg group. Normal vital sign variations due to the nasal instillation of midazolam were observed in both groups. Some minor respiratory depression was observed in the 0.2 mg/kg group. One instance of severe respiratory depression was observed in the higher dose group. Although both doses of midazolam were effective, no benefit was observed using a dose of 0.3 mg/kg. Indeed, a 0.3 mg/kg intranasal dose of midazolam may actually produce severe respiratory depression.
Abstract Background Endothelial cells (ECs) make up the innermost layer throughout the entire vasculature. Their phenotypes and physiological functions are initially regulated by developmental signals and extracellular stimuli. The underlying molecular mechanisms responsible for the diverse phenotypes of ECs from different organs are not well understood. Results To characterize the transcriptomic and epigenomic landscape in the vascular system, we cataloged gene expression and active histone marks in nine types of human ECs (generating 148 genome-wide datasets) and carried out a comprehensive analysis with chromatin interaction data. We developed a robust procedure for comparative epigenome analysis that circumvents variations at the level of the individual and technical noise derived from sample preparation under various conditions. Through this approach, we identified 3765 EC-specific enhancers, some of which were associated with disease-associated genetic variations. We also identified various candidate marker genes for each EC type. We found that the nine EC types can be divided into two subgroups, corresponding to those with upper-body origins and lower-body origins, based on their epigenomic landscape. Epigenomic variations were highly correlated with gene expression patterns, but also provided unique information. Most of the deferentially expressed genes and enhancers were cooperatively enriched in more than one EC type, suggesting that the distinct combinations of multiple genes play key roles in the diverse phenotypes across EC types. Notably, many homeobox genes were differentially expressed across EC types, and their expression was correlated with the relative position of each organ in the body. This reflects the developmental origins of ECs and their roles in angiogenesis, vasculogenesis and wound healing. Conclusions This comprehensive analysis of epigenome characterization of EC types reveals diverse transcriptional regulation across human vascular systems. These datasets provide a valuable resource for understanding the vascular system and associated diseases.
