Facilitators and barriers affecting the implementation of e-health for chronic respiratory diseases in remote settings: a qualitative evidence synthesis.

Background: Chronic respiratory diseases are important causes of disability and mortality globally. Their incidence may be higher in remote locations where healthcare is limited and risk factors, such as smoking and indoor air pollution, are more prevalent. E-health could overcome some healthcare access obstacles in remote locations, but its utilisation has been limited.

Metal oxide multilayer hard mask system for 3D nanofabrication.

We demonstrate the preparation and exploitation of multilayer metal oxide hard masks for lithography and 3D nanofabrication. Atomic layer deposition (ALD) and focused ion beam (FIB) technologies are applied for mask deposition and mask patterning, respectively. A combination of ALD and FIB was used and a patterning procedure was developed to avoid the ion beam defects commonly met when using FIB alone for microfabrication.

Selective etching of focused gallium ion beam implanted regions from silicon as a nanofabrication method.

A focused ion beam (FIB) is otherwise an efficient tool for nanofabrication of silicon structures but it suffers from the poor thermal stability of the milled surfaces caused by segregation of implanted gallium leading to severe surface roughening upon already slight annealing. In this paper we show that selective etching with KOH:H2O2 solutions removes the surface layer with high gallium concentration while blocking etching of the surrounding silicon and silicon below the implanted region. This remedies many of the issues associated with gallium FIB nanofabrication of silicon.

The effects of xenon anesthesia on the relationship between cerebral glucose metabolism and blood flow in healthy subjects: a positron emission tomography study.

Background: General anesthetics can alter the relationship between regional cerebral glucose metabolism (rCMR(glc)) and blood flow (rCBF). In this positron emission tomography study, our aim was to assess both rCMR(glc) and rCBF in the same individuals during xenon anesthesia.

Methods: (18)F-labeled fluorodeoxyglucose and (15)O-labeled water were used to determine rCMR(glc) and rCBF, respectively, in five healthy male subjects at baseline (awake) and during 1 minimum alveolar anesthetic concentration of xenon.

Measurement of GABAA receptor binding in vivo with [11C]flumazenil: a test-retest study in healthy subjects.

[(11)C]Flumazenil is widely used in positron emission tomography (PET) studies to measure GABA(A) receptors in vivo in humans. Although several different methods have been applied for the quantification of [(11)C]flumazenil binding, the reproducibility of these methods has not been previously examined. The reproducibility of a single bolus [(11)C]flumazenil measurements was studied by scanning eight healthy volunteers twice during the same day.

Xenon does not affect gamma-aminobutyric acid type A receptor binding in humans.

Background: The noble gas xenon acts as an anesthetic with favorable hemodynamic and neuroprotective properties. Based on animal and in vitro data, it is thought to exert its anesthetic effects by inhibiting glutamatergic signaling, but effects on gamma-aminobutyric acid type A (GABA(A)) receptors also have been reported. The mechanism of anesthetic action of xenon in the living human brain still remains to be determined.

Bispectral index, entropy, and quantitative electroencephalogram during single-agent xenon anesthesia.

Background: The aim was to evaluate the performance of anesthesia depth monitors, Bispectral Index (BIS) and Entropy, during single-agent xenon anesthesia in 17 healthy subjects.

Methods: After mask induction with xenon and intubation, anesthesia was continued with xenon only. BIS, State Entropy and Response Entropy, and electroencephalogram were monitored throughout induction, steady-state anesthesia, and emergence.

Effects of xenon anesthesia on cerebral blood flow in humans: a positron emission tomography study.

Background: Animal studies have demonstrated a strong neuroprotective property of xenon. Its usefulness in patients with cerebral pathology could be compromised by deleterious effects on regional cerebral blood flow (rCBF).

Methods: 15O-labeled water was used to determine rCBF in nine healthy male subjects at baseline and during 1 minimum alveolar concentration (MAC) of xenon (63%).

Increase in high frequency EEG activity explains the poor performance of EEG spectral entropy monitor during S-ketamine anesthesia.

Objective: To study the effects of S-ketamine on the EEG and to investigate whether spectral entropy of the EEG can be used to assess the depth of hypnosis during S-ketamine anesthesia.

Methods: The effects of sub-anesthetic (159 (21); mean (SD) ng/ml) and anesthetic (1,959 (442) ng/ml) serum concentrations of S-ketamine on state entropy (SE), response entropy (RE) and classical EEG spectral power variables (recorded using the Entropy Module, GE Healthcare, Helsinki, Finland) were studied in 8 healthy males. These EEG data were compared with EEG recordings from 6 matching subjects anesthetized with propofol.

Subanesthetic ketamine does not affect 11C-flumazenil binding in humans.

Positron emission tomography (PET) studies suggest that propofol and inhaled anesthetics increase (11)C-flumazenil binding in the living human brain, thus supporting the involvement of gamma-aminobutyric acid type A (GABA(A)) receptors in the mechanism of action of these drugs. Ketamine produces its anesthetic effects primarily by N-methyl-d-aspartate receptor antagonism, but it may also have GABA(A) receptor agonistic properties. By using PET, we studied the cerebral (11)C-flumazenil binding in 10 healthy subjects before and during a subanesthetic racemic ketamine infusion reaching a serum concentration of 350 +/- 42 ng/mL.

S-ketamine anesthesia increases cerebral blood flow in excess of the metabolic needs in humans.

Background: Animal studies have demonstrated neuroprotective properties of S-ketamine, but its effects on cerebral blood flow (CBF), metabolic rate of oxygen (CMRO2), and glucose metabolic rate (GMR) have not been comprehensively studied in humans.

Methods: Positron emission tomography was used to quantify CBF and CMRO2 in eight healthy male volunteers awake and during S-ketamine infusion targeted to subanesthetic (150 ng/ml) and anesthetic (1,500-2,000 ng/ml) concentrations. In addition, subjects' GMRs were assessed awake and during anesthesia.

Sevoflurane and propofol increase 11C-flumazenil binding to gamma-aminobutyric acidA receptors in humans.

Based on in vitro studies and animal data, most anesthetics are supposed to act via gamma-aminobutyric acid type A (GABA(A)) receptors. However, this fundamental characteristic has not been extensively investigated in humans. We studied (11)C-flumazenil binding to GABA(A) receptors during sevoflurane and propofol anesthesia in the living human brain using positron emission tomography (PET).

Effects of subanesthetic ketamine on regional cerebral glucose metabolism in humans.

Background: The authors have recently shown with positron emission tomography that subanesthetic doses of racemic ketamine increase cerebral blood flow but do not affect oxygen consumption significantly. In this study, the authors wanted to assess the effects of racemic ketamine on regional glucose metabolic rate (rGMR) in similar conditions to establish whether ketamine truly induces disturbed coupling between cerebral blood flow and metabolism.

Methods: 18F-labeled fluorodeoxyglucose was used as a positron emission tomography tracer to quantify rGMR on 12 brain regions of interest of nine healthy male volunteers at baseline and during a 300-ng/ml ketamine target concentration level.

Focal and global cortical hypometabolism in patients with newly diagnosed infantile spasms.

Objective: To evaluate the occurrence and prognostic importance of focal defects in cerebral cortical glucose metabolism in infants with newly diagnosed symptomatic and cryptogenic infantile spasms.

Patients And Methods: Ten children with symptomatic and seven with cryptogenic infantile spasms underwent MRI, video-EEG, and PET using fluorodeoxyglucose as a tracer within 2 weeks of diagnosis. PET was repeated at 1 year of age in 12 patients.

[Role of external biliary drainage in common bile duct lithiasis. Apropos of 172 case reports].

A series of 172 lithiasis of the common bile duct has been analysed. Priority has always been given to the external drainage by a T tube. It seems to be the simplest method, with the lowest morbidity.