Quench of magnetic resonance imaging system refers to the process that the superconducting condition inside the magnet is destroyed due to some reason. The large current stored in the coil is quickly converted into heat at the place where the resistance is formed, and a large amount of liquid helium in the magnet is evaporated. If it happens, it will cause huge loss to the user. We introduce the real cases of 1.5 T magnetic resonance imaging system's quench fault, maintenance treatment and management improvement, which can be used for reference by various medical institutions, so as to better strengthen the operation and maintenance management of magnetic resonance imaging system, so as to avoid the occurrence of out of tolerance fault, and do a good job in the guarantee work after the out of tolerance fault.
Helium ; Magnetic Resonance Imaging ; Magnets

PURPOSE: Direct application of atmospheric-pressure plasma jets (APPJs) has been established as an effective method of microbial decontamination. This study aimed to investigate the bactericidal effect of direct application of an APPJ using helium gas (He-APPJ) on Porphyromonas gingivalis biofilms on sandblasted and acid-etched (SLA) titanium discs. METHODS: On the SLA discs covered by P. gingivalis biofilms, an APPJ with helium (He) as a discharge gas was applied at 3 different time intervals (0, 3, and 5 minutes). To evaluate the effect of the plasma itself, the He gas–only group was used as the control group. The bactericidal effect of the He-APPJ was determined by the number of colony-forming units. Bacterial viability was observed by confocal laser scanning microscopy (CLSM), and bacterial morphology was examined by scanning electron microscopy (SEM). RESULTS: As the plasma treatment time increased, the amount of P. gingivalis decreased, and the difference was statistically significant. In the SEM images, compared to the control group, the bacterial biofilm structure on SLA discs treated by the He-APPJ for more than 3 minutes was destroyed. In addition, the CLSM images showed consistent results. Even in sites distant from the area of direct He-APPJ exposure, decontamination effects were observed in both SEM and CLSM images. CONCLUSIONS: He-APPJ application was effective in removing P. gingivalis biofilm on SLA titanium discs in an in vitro experiment.
Bacterial Load ; Biofilms ; Decontamination ; Helium ; In Vitro Techniques ; Methods ; Microbial Viability ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Plasma Gases ; Plasma ; Porphyromonas gingivalis ; Porphyromonas ; Stem Cells ; Titanium

OBJECTIVE: To investigate the effects of simulated 100 m Trimix conventional diving on tissue inflammatory cytokines in rabbits. METHODS: Eight New Zealand rabbits were performed a simulated 100 m Trimix conventional diving program which was established according to the Haldane theory. The expression levels of interferon-gamma(IFN-), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-8 (IL-8), myeloperoxidase(MPO) and matrix metallo proteinase-9 (MMP-9) in rabbits lung and brain tissues were detected by Elisa after diving decompression. The tissue wet/dry ratio was calculated. The serum levels of superoxide dismutase (SOD),glutathione(GSH), catalase(CAT), malondiadehyde(MDA) and lipid peroxide(LPO) were detected by Elisa method in rabbits before and after diving. RESULTS: The expressions of IFN-, TNF-α, IL-6, IL-8, MPO and MMP-9 in simulated diving group rabbits were significantly increased compared with the intact group(<0.05, <0.01); the simulated diving rabbits tissues wet/dry ratio had no significant changes compared with the intact group. After diving, the activities of SOD and GSH were decreased significantly (<0.01), while the contents of CAT, MDA and LPO were increased significantly (<0.01). CONCLUSIONS The simulated 100 m Trimix conventional diving had significant impact on oxidative stress and inflammatory reaction in rabbits, the results of wet/dry ratio showed that the diving rabbits had no tissue edema after decompression.
Animals ; Catalase ; Diving ; physiology ; Glutathione ; Helium ; Inflammation ; Interleukin-6 ; Interleukin-8 ; Malondialdehyde ; Matrix Metalloproteinase 9 ; Nitrogen ; Oxidative Stress ; Oxygen ; Peroxidase ; Rabbits ; Superoxide Dismutase ; Tumor Necrosis Factor-alpha

PURPOSE: The purpose of this report is to describe the proton therapy system at Samsung Medical Center (SMC-PTS) including the proton beam generator, irradiation system, patient positioning system, patient position verification system, respiratory gating system, and operating and safety control system, and review the current status of the SMC-PTS. MATERIALS AND METHODS: The SMC-PTS has a cyclotron (230 MeV) and two treatment rooms: one treatment room is equipped with a multi-purpose nozzle and the other treatment room is equipped with a dedicated pencil beam scanning nozzle. The proton beam generator including the cyclotron and the energy selection system can lower the energy of protons down to 70 MeV from the maximum 230 MeV. RESULTS: The multi-purpose nozzle can deliver both wobbling proton beam and active scanning proton beam, and a multi-leaf collimator has been installed in the downstream of the nozzle. The dedicated scanning nozzle can deliver active scanning proton beam with a helium gas filled pipe minimizing unnecessary interactions with the air in the beam path. The equipment was provided by Sumitomo Heavy Industries Ltd., RayStation from RaySearch Laboratories AB is the selected treatment planning system, and data management will be handled by the MOSAIQ system from Elekta AB. CONCLUSION: The SMC-PTS located in Seoul, Korea, is scheduled to begin treating cancer patients in 2015.
Cyclotrons ; Helium ; Humans ; Korea* ; Metallurgy ; Particle Accelerators ; Patient Positioning ; Proton Therapy* ; Protons* ; Radiation Oncology ; Respiratory System ; Seoul

OBJECTIVETo explore the underwater decompression schedule for 100 m Trimix conventional diving operations and evaluate its safety through a simulated rabbits Trimix conventional diving.

METHODSAccording to the Haldane theory, the assumed time units, the classification of tissue compartments, the nitrogen super-saturation safety coefficient and the selection of methods used for the calculation of the simulated 100 m Trimix conventional diving schedule were properly selected, and the calculating method for the dive decompression schedule was thus firmly established. In our experiments, five tissue compartments were selected during the calculation of decompression schedule: 5 min, 10 min, 20 min, 40 min and 75 min, and the nitrogen super-saturation safety coefficient was calculated by 1.6. Eight New Zealand rabbits were performed a simulated 100 m Trimix dive program which was established according to the Haldane theory, and eight rabbits for intact group. The tissues wet/dry ratio and ethology were detected and observed before and after the simulated diving to evaluate the safety of decompression schedule.

RESULTSBy using the developed underwater decompression schedule, abnormal ethology changes in rabbits could not be observed after compression and decompression to the surface; and the tissues wet/dry ratio of simulated diving rabbits had no significant changes compared with the intact group (P > 0.05).

CONCLUSIONThe decompression schedule calculated by Haldane theory seemed to be safe and reliable, the diving breathing gas concentration did not cause oxygen toxicity and nitrogen narcosis among the dive rabbits, and dive efficiency was greatly improved by using enriched oxygen gas in UPTD safety range during decompression.

Animal Experimentation ; Animals ; Decompression ; Diving ; Helium ; Nitrogen ; Oxygen ; Rabbits

BACKGROUNDAcute exacerbation of chronic obstructive pulmonary disease (AECOPD) is a common condition, which affects not only the quality of life of patients but also their prognosis. The purpose of this study was to explore the effects of an inhaled salbutamol sulfate solution and an inhalation suspension of the glucocorticoid budesonide that were atomized with heliox to treat patients with AECOPD.

METHODSTwenty-three patients with AECOPD were divided into a treatment group (He/O2 = 70%/30%) and a control group (N2/O2 = 70%/30%). The salbutamol sulfate and budesonide were administered by inhalation twice a day for 7 days. Vital signs, arterial blood gas levels, pulmonary function and the levels of serum myostatin (sMSTN) were measured and lung vibration imaging was performed.

RESULTSWe found that the PaO2 and PaCO2 values were not significantly different between the two groups at the various time points (P > 0.05). There were also no significant differences in any of the parameters of pulmonary function between the two groups. However, after baseline correction, the increase rate of the forced expiratory volume in one second (FEV1), the forced vital capacity (FVC), and the maximum minute ventilation (MVV) appeared to be significantly increased at some time points compared with the baseline (before treatment) in both groups (P < 0.05). Although the values of quantitative lung distribution (QLD) for different regions and the levels of sMSTN were slightly different between the two groups, the repeated measures analysis of variance (ANOVA) revealed that there were no significant differences between the two groups or within any group (P > 0.05).

CONCLUSIONAlthough the use of heliox as a driving gas can improve symptoms and benefit patients with AECOPD, the heliox treatment group did not have significant differences in arterial blood gases, lung function, lung vibration response imaging or the levels of sMSTN compared with the control group. (Chinese Clinical Trial Register Center ChiCTRTRC-00000273).

Administration, Inhalation ; Aged ; Albuterol ; administration & dosage ; therapeutic use ; Budesonide ; administration & dosage ; therapeutic use ; Drug Interactions ; Female ; Helium ; administration & dosage ; therapeutic use ; Humans ; Male ; Middle Aged ; Oxygen ; administration & dosage ; therapeutic use ; Prospective Studies ; Pulmonary Disease, Chronic Obstructive ; drug therapy

A 39-year-old man, his 35-year-old wife, and their 13-year-old daughter were found dead in their home. The man and his daughter were found lying in her bedroom, with his head wrapped in a plastic bag connected to four helium gas cylinders by green polypropylene tubes. Fragments of the burnt ignition briquette were found in the bucket located at her feet. His wife was found in a decomposed state lying on her right side in her bedroom. Autopsy findings for the man were unremarkable except for cherry pink lividity; the blood carboxyhemoglobin concentration was 73%. Autopsy findings were unremarkable for the woman as well, except for a few petechial hemorrhages and conjunctival congestion. The daughter showed no definite abnormalities; however, her blood and lung contained helium gas. The deceased man's suicide note, evidence gathered at the scene, and postmortem examination revealed that this was a case of dyadic death.
Adolescent ; Adult ; Asphyxia ; Autopsy* ; Carboxyhemoglobin ; Deception ; Estrogens, Conjugated (USP) ; Female ; Foot ; Head ; Helium* ; Hemorrhage ; Humans ; Lung ; Nuclear Family ; Plastics ; Polypropylenes ; Prunus ; Spouses ; Suicide

Since the book "Final Exit: The Practicalities of Self-Deliverance and Assisted Suicide for the Dying" was published in 1991, there has been a worldwide increase in the number of cases of suicidal asphyxiation using helium gas. However, no domestic reports have been published thus far. Recently, we encountered a case of asphyxial suicide by inhalation of helium from inside a plastic bag. Subsequently, we reviewed the records of the Scientific Crime Analysis System of National Police Agency of Korea. There were 17 cases of helium-associated asphyxial suicides between January 1, 2000 and June 30, 2012. The average age of the deceased was 30.6 years with a male to female ratio of approximately 5:1. Thirteen of 17 such deaths occurred in the victims'houses. In all cases, the method of death involved placing a plastic bag over the head with a hose attached to helium tanks. In 6 of 17 cases, the decedents had psychiatric disorders such as depression. As neither characteristic signs of death nor conventional methods for detecting helium gas exist, a thorough investigation of the death scene and the decedents'environment is extremely vital for confirming death due to helium asphyxiation.
Crime ; Depression ; Female ; Head ; Helium ; Humans ; Inhalation ; Korea ; Male ; Plastics ; Police ; Suicide ; Suicide, Assisted

OBJECTIVETo investigate the changes of adhesion molecules, cyclic adenosine monophosphate(cAMP) and cyclic guanosine monophosphate (cGMP) in divers post 480 heliox saturation diving.

METHODSFour divers were compressed within 96 hours to depths of 480 m with heliox-oxygen and held at the designated depth for 49 hours, excursion to 493 m during their saturation stay, then decompressed within 302 hours to the surface. The blood samples were collected before compression and post decompression, the expression level of intercellular adhesion molecule-1(ICAM-1), E-selectin, P-selectin, cAMP, cGMP were detected with ELISA analysis box.

RESULTSCompared with the levels of CAMs before compression, the levels of ICAM-1, E-selectin, P-selectin and cGMP in the serum were changed post decompression (P > 0.05). The levels of cAMP were significantly elevated post decompression (629.91 +/- 75.01) nmol/L vs (66.72 +/- 83.15) (P < 0.05).

CONCLUSIONThe decompression schedule in this heliox saturation diving is safe, the decompression sickness pathology in this diving has not been induced. But the stress response of divers are enhanced by this great depth saturation diving.

Cyclic AMP ; blood ; Diving ; physiology ; E-Selectin ; blood ; Helium ; Humans ; Intercellular Adhesion Molecule-1 ; blood ; Oxygen ; P-Selectin ; blood

Every operation could have a fire emergency, especially in the case of a tracheostomy. When a flammable gas meets a source of heat, the danger of fire is remarkable. A tracheal tube filled with a high concentration of oxygen is also a great risk factor for fire. Intra-tracheal tube fire is a rare, yet critical emergency with catastrophic consequences. Thus, numerous precautions are taken during a tracheostomy like, use of a special tube to prevent laser damage, ballooning of the tube with normal saline instead of air, and dilution of FiO2 with helium or nitrogen. Since the first recorded cases on tube fires, most of the fires were initiated in the balloon and the tip. In the present case report, however, we came across a fire incidence, which originated from the wire.
Airway Management ; Burns ; Emergencies ; Fires ; Helium ; Hot Temperature ; Incidence ; Nitrogen ; Oxygen ; Porphyrins ; Risk Factors ; Tracheostomy