Tetrodotoxin is a neurotoxin produced by about 90 species of puffer fish and causes paralysis of central nervous system and peripheral nerves by blocking the movement of all monovalent cations. Ingestion of tetrodotoxin produces clinical manifestations such as paresthesias(within 10-45 min), vomiting, lightheadedness, salivation, muscle twitching, dysphagia, difficulty in speaking, convulsion and death that expressed by cardiopulmonary arrest with loss of brain stem reflex sometimes. Tetrodotoxin prevents or delays ischemia induced neuronal death by way of following 3 mechanisms. Firstly, it reduces the energy demand of the brain tissues. Secondly, it delays or even prevents anoxic depolarization. Finally, it diminishes ischemia induced cell swelling and cerebral edema. We report a case of puffer fish poisoning which presented with cardiopulmonary arrest and loss of brain stem reflex, but completely recovered by aggressive cardiopulmonary resuscitation.
Brain ; Brain Edema ; Brain Stem ; Cardiopulmonary Resuscitation ; Cations, Monovalent ; Central Nervous System ; Deglutition Disorders ; Dizziness ; Eating ; Heart Arrest ; Ischemia ; Neurons ; Paralysis ; Peripheral Nerves ; Poisoning* ; Reflex ; Salivation ; Seizures ; Tetraodontiformes* ; Tetrodotoxin ; Vomiting

Age-related hearing loss (AHL) is one of the most common sensory disorders among elderly persons. The inwardly rectifying potassium channel 5.1 (Kir5.1) plays a vital role in regulating cochlear K(+) circulation which is necessary for normal hearing. The distribution of Kir5.1 in C57BL/6J mice cochleae, and the relationship between the expression of Kir5.1 and the etiology of AHL were investigated. Forty C57BL/6J mice were randomly divided into four groups at 4, 12, 24 and 52 weeks of age respectively. The location of Kir5.1 was detected by immunofluorescence technique. The mRNA and protein expression of Kir5.1 was evaluated in mice cochleae using real-time polymerase-chain reactions (RT-PCR) and Western blotting respectively. Kir5.1 was detected in the type II and IV fibrocytes of the spiral ligament in the cochlear lateral wall of C57BL/6J mice. The expression levels of Kir5.1 mRNA and protein in the cochleae of aging C57BL/6J mice were down-regulated. It was suggested that the age-related decreased expression of Kir5.1 in the lateral wall of C57BL/6J mice was associated with hearing loss. Our results indicated that Kir5.1 may play an important role in the pathogenesis of AHL.
Aging ; genetics ; metabolism ; Animals ; Cations, Monovalent ; Fluorescent Antibody Technique ; Gene Expression Regulation ; Ion Transport ; Mice ; Mice, Inbred C57BL ; Microtomy ; Potassium ; metabolism ; Potassium Channels, Inwardly Rectifying ; genetics ; metabolism ; Presbycusis ; genetics ; metabolism ; physiopathology ; RNA, Messenger ; genetics ; metabolism ; Spiral Ligament of Cochlea ; metabolism ; physiopathology ; ultrastructure

No abstract available.
Osteoporosis ; Proton Pumps ; Protons

No abstract available.
Craniocerebral Trauma* ; Head* ; Protons*

We studied a Monte Carlo simulation of the proton beam delivery system at the National Cancer Center (NCC) using the Geant4 Monte Carlo toolkit and tested its feasibility as a dose verification framework. The Monte Carlo technique for dose calculation methodology has been recognized as the most accurate way for understanding the dose distribution in given materials. In order to take advantage of this methodology for application to externalbeam radiotherapy, a precise modeling of the nozzle elements along with the beam delivery path and correct initial beam characteristics are mandatory. Among three different treatment modes, double/single.scattering, uniform scanning and pencil beam scanning, we have modeled and simulated the double.scattering mode for the nozzle elements, including all components and varying the time and space with the Geant4.8.2 Monte Carlo code. We have obtained simulation data that showed an excellent correlation to the measured dose distributions at a specific treatment depth. We successfully set up the Monte Carlo simulation platform for the NCC proton therapy facility. It can be adapted to the precise dosimetry for therapeutic proton beam use at the NCC. Additional Monte Carlo work for the full proton beam energy range can be performed.
Proton Therapy ; Protons* ; Radiotherapy

No abstract available.
Proton Pumps ; Protons

No abstract available.
Biopsy* ; Brain* ; Protons*

No abstract available.
Proton Pumps* ; Protons*

The main benefit of proton therapy over photon beam radiotherapy is the absence of exit dose, which offers the opportunity for highly conformal dose distributions to target volume while simultaneously irradiating less normal tissue. For proton beam therapy two patient specific beam modifying devices are used. The aperture is used to shape the transverse extension of the proton beam to the shape of the tumor target and a patient-specific compensator attached to the block aperture when required and used to modify the beam range as required by the treatment plan for the patient. A block of range shifting material, shaped on one face in such a way that the distal end of the proton field in the patient takes the shape of the distal end of the target volume. The mechanical quality assurance of range compensator is an essential procedure to confirm the 3 dimensional patient-specific dose distributions. We proposed a new quality assurance method for range compensator based on image processing using X-ray tube of proton therapy treatment room. The depth information, boundaries of each depth of plan compensatorfile and x-ray image of compensator were analyzed and presented over 80% matching results with proposed QA program.
Humans ; Proton Therapy ; Protons

No abstract available.
Eosinophilia* ; Proton Pumps* ; Protons*