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1.
Radiat Res ; 171(5): 615-21, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19580497

RESUMEN

The blood-brain barrier (BBB) consists of tight junctions between the endothelial cells that line the capillaries in the central nervous system. This structure protects the brain, and neurological damage could occur if it is compromised. Several publications by researchers at Lund University have reported alterations in the BBB after exposure to low-power 915 MHz energy. These publications increased the level of concern regarding the safety of wireless communication devices such as mobile phones. We performed a confirmation study designed to determine whether the BBB is altered in rats exposed in a transverse electromagnetic (TEM) transmission line cell to 915 MHz energy at parameters similar to those in the Lund University studies. Unanesthetized rats were exposed for 30 min to either continuous-wave or modulated (16 or 217 Hz) 915 MHz energy at power levels resulting in whole-body specific absorption rates (SARs) of 0.0018-20 W/kg. Albumin immunohistochemistry was performed on perfused brain tissue sections to determine the integrity of the BBB. Chi-square analysis revealed no significant increase in albumin extravasation in any of the exposed animals compared to the sham-exposed or home cage control animals.


Asunto(s)
Albúminas/farmacocinética , Barrera Hematoencefálica/efectos de la radiación , Ondas de Radio , Animales , Inmunohistoquímica , Masculino , Dosis de Radiación , Ratas , Ratas Endogámicas F344
2.
Forensic Sci Med Pathol ; 5(1): 2-10, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19330471

RESUMEN

In previous studies, repeated 5-s exposures of anesthetized pigs to an electronic control device (TASER International's Advanced TASER X26 device) resulted in acidosis and increases in blood electrolytes. In the current study, experiments were performed to investigate the effects of longer continuous exposures to a different electronic-control-device waveform. After intramuscular injection of tiletamine HCl and zolazepam HCl, anesthesia was maintained with propofol infusion. Ten pigs were exposed to either 30- or 60-s applications of an electronic waveform similar to the TASER-X26 device. Transient increases in potassium, and sodium were consistent with previous reports in the literature dealing with studies of muscle stimulation or exercise. Blood pH was significantly decreased after exposure, but subsequently returned to baseline levels. Lactate was highly elevated and remained somewhat increased even after three hrs. Serum myoglobin was increased after exposure and remained elevated for the 3-h follow-up period. Acidosis would appear to be one of the major concerns with long-duration (e.g., several min) exposures over a short period of time. Even with the extremely low pH immediately after exposure, all animals survived. On the basis of these results, further development of useful continuous-exposure electronic control devices is at least feasible, with the caveat that some medical monitoring of subjects may be required.


Asunto(s)
Electrochoque/instrumentación , Animales , Análisis Químico de la Sangre , Glucemia/análisis , Dióxido de Carbono/sangre , Creatina Quinasa/sangre , Medicina Legal , Frecuencia Cardíaca , Hematócrito , Concentración de Iones de Hidrógeno , Ácido Láctico/sangre , Masculino , Contracción Muscular , Mioglobina/sangre , Oxígeno/sangre , Potasio/sangre , Respiración , Sodio/sangre , Sus scrofa , Factores de Tiempo
3.
Forensic Sci Int ; 175(2-3): 166-70, 2008 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-17630236

RESUMEN

In a previous study, 18 repeated exposures of anaesthetized swine to an electro-muscular incapacitating device (TASER International's ADVANCED TASER X26 electronic control device) resulted in acidosis and increases in blood electrolytes. In the current study, experiments were performed to investigate effects of a more typical scenario of repeated exposures of the device on muscle contraction and changes in blood factors. Ten swine were exposed for 5s, followed by a 5-s period of no exposure, three times. Selected blood factors were monitored for 3h following exposure. Transient increases in blood glucose, lactate, sodium, potassium, calcium, and pCO(2) were consistent with previous reports in the literature dealing with studies of muscle stimulation or exercise. Blood pH was decreased immediately following exposure, but subsequently returned toward a normal level. Oxygen saturation (measured by pulse oximetry) was not changed significantly. In conclusion, three repeated TASER device exposures had only transient effects on blood factors, which all returned to pre-exposure levels, with the exception of hematocrit (which remained elevated after 3h). Since the increase in this factor was less than that which may occur after short periods of exercise, it is unlikely that this would be an indicator of any serious harm.


Asunto(s)
Electrochoque/instrumentación , Animales , Glucemia/análisis , Calcio/sangre , Dióxido de Carbono/sangre , Creatina Quinasa/sangre , Medicina Legal , Frecuencia Cardíaca/fisiología , Hematócrito , Concentración de Iones de Hidrógeno , L-Lactato Deshidrogenasa/sangre , Masculino , Contracción Muscular/fisiología , Mioglobina/sangre , Oxígeno/sangre , Potasio/sangre , Respiración , Sodio/sangre , Sus scrofa , Troponina I/sangre , Troponina T/sangre
4.
Mil Med ; 172(2): 182-9, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17357774

RESUMEN

There have been many previous claims of nonlethal acoustic weapon effects, mostly in the popular rather than the scientific literature. Anecdotal reports of extraordinary effects can make meaningful assessment and review of this area very difficult. Acoustics research has shown that the nonlethal weapon capabilities of audible sound generators have been grossly overstated. Although high-intensity infrasound significantly disrupted animal behavior in some experiments, the generation of such energy in a volume large enough to be of practical use is unlikely because of basic physical principles. On the basis of experimentation completed to date at a number of institutions, it seems unlikely that high-intensity acoustic energy in the audible, infrasonic, or low-frequency range can provide a device suitable for use as a nonlethal weapon.


Asunto(s)
Acústica/instrumentación , Traumatismos por Explosión/etiología , Audición/efectos de la radiación , Personal Militar , Traumatismos por Radiación/etiología , Guerra , Animales , Salud Global , Humanos , Sonido/efectos adversos
5.
Forensic Sci Int ; 161(1): 20-30, 2006 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-16289999

RESUMEN

Repeated exposure to electro-muscular incapacitating devices could result in repetitive, sustained muscle contraction, with little or no muscle recovery period. Therefore, rhabdomyolysis and other physiological responses, including acidosis, hyperkalaemia, and altered levels of muscle enzymes in the blood, would be likely to occur. Experiments were performed to investigate effects of repeated exposures of TASER International's Advanced TASER X26 on muscle contraction and resultant changes in blood factors in an anaesthetized swine model. A total of 10 animals were used. Six swine were exposed for 5 s, followed by a 5-s period of no exposure, repeatedly for 3 min. (In five of the animals, after a 1-h delay, a second 3-min exposure period was added.) The remaining four animals were used for an additional pilot study. All four limbs of each animal exhibited contraction even though the electrodes were positioned in areas at some distances from the limbs. The degree of muscle contraction generated during the second exposure period was significantly lower than that in the first exposure series. This finding was consistent with previous studies showing that prolonged activity in skeletal muscle will eventually result in a decline of force production. There were some similarities in blood sample changes in the current experiments with previous studies of muscular exercise. Thus problems concerning biological effects of repeated TASER exposures may be related, not directly to the "electric output" per se, but rather to the resulting contraction of muscles (and related interruption of respiration) and subsequent sequelae. Transient increases in hematocrit, potassium, and sodium were consistent with previous reports in the literature dealing with studies of muscle stimulation or exercise. It is doubtful that these short-term elevations would have any serious health consequences in a healthy individual. Blood pH was significantly decreased for 1h following exposure, but subsequently returned toward a normal level. Leg muscle contractions and decreases in respiration each appeared to contribute to the acidosis. Lactate was highly elevated, with a slow return (time course greater than 1 h) to baseline. Other investigators have reported profound metabolic acidosis during restraint-associated cardiac arrest. Since restraint often occurs immediately after TASER exposure, this issue should be considered in further development of deployment concepts. On the basis of the results of the current studies, the repeated use of electro-muscular incapacitating devices in a short period of time is, at least, feasible, with the caveat that some medical monitoring of subjects may be required (to observe factors such as lactate and acidosis).


Asunto(s)
Acidosis/sangre , Traumatismos por Electricidad/sangre , Estimulación Eléctrica/instrumentación , Ácido Láctico/sangre , Animales , Glucemia/análisis , Medicina Legal , Frecuencia Cardíaca , Hematócrito , Modelos Animales , Contracción Muscular , Potasio/sangre , Respiración , Sodio/sangre , Sus scrofa
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