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Biomedical subjects

M J Galvin

Publications and source records attributed to M J Galvin.

At least 19 recordsLinked to original sources
PubMed2000

Evaluation of in vitro effects of 50 and 60 Hz magnetic fields in regional EMF exposure facilities.

A weak association between magnetic-field exposure and increased incidences of cancer has been reported. While alterations in cellular processes after in vitro magnetic-field exposures have also been reported to provide plausibility for this association, other laboratories have been unable to repeat the findings. As part of an accelerated electric- and magnetic-field (EMF) research program, the National Institute of Environmental Health Sciences with the Department of Energy identified the replication of the published positive effects as a priority. Regional EMF exposure facilities were established to investigate major in vitro effects from the literature. These included effects on gene expression, intracellular calcium, colony growth in soft agar, and ornithine decarboxylase activity. The laboratories that first reported these effects provided experimental protocols, cell lines, and other relevant experiment details. Regional facility studies included sham/sham exposures (no applied field in either chamber) and were done in a blinded fashion to minimize investigator bias. In nearly all experiments, no effects of magnetic-field exposure were found. The effort provided insight into dealing with the difficulty of replication of subtle effects in complex biological systems. Experimental techniques provided some clues for the differences in experimental results between the regional facility and the original investigator. Studies of subtle effects require extraordinary efforts to confirm that the effect can be attributed to the applied exposure.

Animals↗
PubMed1992

Effects of blood contamination on equine peritoneal fluid analysis.

Peritoneal fluid and blood was collected from 8 healthy adult horses. Four 1-ml aliquots of peritoneal fluid from each horse were then contaminated with 0 ml (normal), 0.05 ml (1 drop), 0.10 ml (2 drops), and 0.20 ml (4 drops) of blood from the same horse. Samples were analyzed for RBC count, nucleated blood cell count, total protein concentration, and nucleated cell differential count. Statistical analysis revealed no significant changes in nucleated cell number, nucleated cell differential, or total protein concentration in peritoneal samples contaminated with blood. The RBC count significantly increased with blood contamination. It was concluded that up to 17% blood contamination of peritoneal fluid in clinically normal horses did not significantly alter interpretation of the nucleated cell count or protein concentration.

Animals↗
PubMed1988

Serum enzymes in hemorrhaged Japanese quail after microwave irradiation during embryogeny.

1. Japanese quail eggs were exposed to 2.45 GHz continuous wave microwave radiation at an incident power density of 5 mW/cm2 and a specific absorption rate of 4.03 mW/g during the first 12 days of embryogeny. 2. After hatching, serum biochemical changes in response to hemorrhagic stress were measured following a hemorrhage of 30% of the calculated total blood volume. 3. Lactate dehydrogenase, beta-glucuronidase, acid phosphatase, glucose and protein were not affected by microwave irradiation during embryogeny either before or after hemorrhage. 4. Microwave irradiation in ovo affected the response of serum glutamic oxaloacetic transaminase activity to hemorrhagic stress in Japanese quail.

Acid Phosphatase↗
PubMed1987

Reproduction of Japanese quail after microwave irradiation (2.45 GHz CW) during embryogeny.

Japanese quail (Coturnix coturnix japonica) embryos were irradiated continuously in ovo with 2.45-GHz continuous wave radiation during the first 12 days of embryogenesis at an incident power of 5 mW/cm2 and a specific absorption rate of 4.03 mW/g. The internal temperature of irradiated and nonirradiated (sham) eggs was 37.5 +/- 0.3 degrees C, which is the optimum temperature for incubating quail eggs. At 35 days after hatching irradiated and sham-irradiated males were paired with irradiated or sham-irradiated females and daily records of reproductive performance were collected through 224 days of age. Progeny were hatched from each of the male-female pairs, and progeny reproductive performance was measured from 35 through 168 days of age. Hatchability was not affected by irradiation during embryogeny. Mortality after hatching, egg production, egg weight, fertility, hatchability of eggs produced, and reproductive performance of the progeny were not affected by irradiation during embryogeny. These observations indicate that irradiation of quail embryos with low-level microwave radiation does not affect the reproductive capacity of the hatchlings or of progeny produced from quail irradiated during incubation.

Animals↗
PubMed1987

Leukocyte numbers during the humoral and cell-mediated immune response of Japanese quail after microwave irradiation in ovo.

1. Coturnix coturnix japonica eggs were exposed to 2.45-GHz continuous wave microwave radiation at an incident power density of 5 mW/cm2 (SAR = 4 mW/g) during the first 12 days of embryogeny. After hatching, leukocyte differential changes were measured in response to an injection with Alectoris graeca chukar red blood cells (CRBC) and in response to a phytohemagglutinin (PHA) injection in irradiated and nonirradiated (sham) quail of both sexes. 2. Microwave irradiation did not affect anti-CRBC hemagglutinin titers, PHA-evoked dermal swelling or leukocyte numbers and percentages. 3. In both the irradiated and sham irradiated males, lymphocyte percentages decreased while heterophil percentages increased after CRBC or PHA injection. 4. In ovo irradiation with microwaves did not alter the time course of either a humoral immune response or a cell-mediated immune response in Japanese quail.

Animals↗
PubMed1986

Influence of pre- and postnatal exposure of rats to 2.45-GHz microwave radiation on neurobehavioral function.

Rats exposed to microwaves prenatally (2,450 MHz, 10 mW/cm2, 3 h/day, days 5-20 of gestation) or perinatally (same as above plus days 2-20 postnatally) were examined by a neurobehavioral test battery on postnatal days 30 and 100. Body mass, locomotor activity, startle to acoustic and air-puff stimuli, fore- and hindlimb grip strength, negative geotaxis, reaction to thermal stimulation, and swimming endurance were assessed. The prenatally and the perinatally exposed rats (male and female) weighted more than sham-exposed rats at 30, but not at 100, days of age. In addition, the perinatally exposed animals had less swimming endurance at 30, but not at 100, days of age relative to sham-exposed rats. For the other measures, only the air-puff startle response was altered and was limited to the prenatally exposed female pups; ie, at postnatal day 30, the startle response was increased in magnitude, and at postnatal day 100, the response was decreased. No other reliable effects were observed. In a second experiment, rats treated as described above were examined for alterations in body mass, locomotor activity, reaction to air-puff stimuli, reaction to thermal stimulation, and swimming endurance at postnatal days 30-36. Again, perinatally exposed rats were larger in body mass and had less swimming endurance compared with sham-exposed rats. The latency to the air-puff startle response was longer in female pups exposed prenatally. These data indicate that altered endurance and gross motor activity result from perinatal exposure to microwave irradiation.

Animals↗
PubMed1986

Cardiovascular, hematologic, and biochemical effects of acute ventral exposure of conscious rats to 2450-MHz (CW) microwave radiation.

In this study the influence of acute (6 hr) exposure to 2450 MHz (CW) microwave radiation on certain cardiovascular, biochemical, and hematologic indices was examined in unanesthetized rats. Under methoxyflurane anesthesia, a catheter was inserted into the right femoral artery, which was used for monitoring blood pressure, heart rate, and blood sampling. Colonic temperature was monitored via a VITEK thermistor probe inserted rectally to a depth of 5 cm. The rat was subsequently placed into a ventilated restraining cage which was located inside an anechoic chamber. The temperature and humidity in the chamber were maintained at 22 +/- 0.5 degrees C and 60 +/- 5% (means +/- S.E.), respectively, during the experimental period. Rats (60) were exposed to either 0 (sham) or 10 mW/cm2 (exposed) for 6 hr. During exposure rats were oriented perpendicular to the E-field, and the measured specific absorption rate (SAR) was 3.7 mW/g. In the sham and exposed rats, the preexposure (time 0) mean +/- S.E. arterial blood pressure (MABP), heart rate, and colonic temperature were approximately 120 +/- 5 mmHg, 450 +/- 10 beats/min, and 37.0 +/- 0.2 degrees C, respectively. In the sham-exposed rats these values remained stable throughout the 6-hr exposure period. In the exposed rats, no effects were noted on MABP or colonic temperature; however after 1 hr of exposure, a significant reduction in heart rate was noted (450 versus 400 beats/min). This decrease in heart rate persisted throughout the remainder of the exposure period. None of the hematologic or biochemical parameters examined were affected by the microwave exposure. Although other mechanisms may be responsible, this decrease in heart rate may have been due to subtle cardiovascular adjustments because of microwave-induced heating with a resultant reduction in resting metabolic rate.

Animals↗
PubMed1986

Response of Japanese quail to hemorrhagic stress after exposure to microwave radiation during embryogeny.

Coturnix coturnix japonica eggs were exposed to 2.45 GHz continuous wave microwave radiation at an incident power density of 5 mW/cm2 (SAR = 4 mW/g) during the first 12 days of embryogeny. After hatching, hematologic changes in response to an acute hemorrhage were measured in exposed and nonexposed (control) juveniles and adults of both sexes. Reticulocyte numbers and percentages were depressed below control numbers at 24 hr postphlebotomy in exposed adult females. Lymphocyte numbers were depressed below control levels at 24 hr postphlebotomy in exposed juvenile and adult males. At 72 hr heterophil numbers were depressed in exposed juvenile and adult males. These data suggest that microwave irradiation during embryogeny affects the ability of Japanese quail to recover from an acute and voluminous hemorrhage and that these radiation effects are small.

Aging↗
PubMed1985

An approach to NMR studies of the metabolism of internal organs using surface coils.

This communication describes a surgical preparation of experimental animals to permit NMR spectroscopic studies of the metabolism of internal organs. In the procedure developed, the layer of protective muscle directly above the organ is removed, but the skin is left intact. NMR studies of the metabolism of the organ can then be carried out using surface coils placed externally over the herniated area. Modified probe and stack designs for use with the surgically modified animals in a conventional NMR spectrometer are described. Phosphorus-31 NMR spectra of liver and kidney of the modified animals have been obtained, and data corresponding to the hepatic response to a load of fructose are presented.

Adenine Nucleotides↗
PubMed1985

Hematological response of Japanese quail to acute hemorrhagic stress.

Hematological and serum biochemical changes in response to hemorrhagic stress were determined in both sexes of juvenile and adult Coturnix coturnix japonica over 3 day period following a mechanical hemorrhage of 30% of the calculated total blood volume. There was an initial shift posthemorrhage towards greater numbers of more mature erythrocytes and fewer circulating reticulocytes. Reticulocytosis was indicated 48-72 hr posthemorrhage. Glucose and lactic acid dehydrogenase levels increased after hemorrhage. Serum beta-glucuronidase was elevated only in adults. Japanese quail seemed to recover from hemorrhage more rapidly than had been reported for chickens, other birds and mammals.

Aging↗
PubMed1985

Hematological response of immunized and serially bled Japanese quail.

Sexually mature female Japanese quail (Coturnix coturnix japonica) were immunized by an intravenous injection with .5 ml of a 7.5% suspension of Chukar partridge (Alectoris graeca chukar) red blood cells (CRBC). Blood samples were collected either serially from one group of quail or a single time from separate groups of quail at 0 (nonimmunized), 3, 6, and 9 days post-immunization. Total anti-CRBC hemagglutinin titers (HA) were measured by a microhemagglutinin procedure. Selected hematological variables were also measured. Mean HA was not affected by serial blood sampling. Total erythrocyte numbers, percent hematocrit, and hemoglobin levels were depressed in serially bled quail at 3 days postimmunization. Reticulocytosis was found in serially bled quail at 6 days postimmunization.

Animals↗
PubMed1985

Teratogenic, biochemical, and histological studies with mice prenatally exposed to 2.45-GHz microwave radiation.

Pregnant CD-1 mice were exposed to 2.45-GHz continuous wave microwave radiation at an incident power density of 30 mW/cm2. The local specific absorption rate near the uterine area (deep colonic location), as determined from time-temperature profiles measured with a Vitek thermistor probe, was 40.2 mW/g. Groups of mice were exposed 8 hr per day through Days 1-6 or 6-15 of pregnancy. Other groups of animals were exposed to an elevated ambient temperature of 31 degrees C which increased the colonic temperature 2.3 degrees C, the same as that produced by the microwaves. Sham-irradiated groups of animals were treated exactly the same as the microwave-exposed animals. For the two conditions, temperature exposed and sham exposed, two groups of animals were used. One group was handled in the same manner as the microwave-irradiated group and the other group was not handled so as to evaluate the effects of stressing the animals by handling. Eleven groups of animals were used in the complete study: five groups for gestational Days 1-6, five groups for gestational Days 6-15, and one group of cage control animals. On Day 18 of gestation the dams of all experimental groups were sacrificed and their reproductive status was determined. The fetuses were examined for visceral and skeletal alterations. Brain cholinesterase activity and histology were evaluated in the groups exposed on Days 6-15. The results show that microwave radiation increases embryo lethality at the early stages of gestation (exposure Days 1-6). Fetal toxicity and teratogenicity were not significantly increased by exposure to microwaves on either Days 1-6 or 6-15 of gestation. Cholinesterase activity and histology of the brain of 18-day-old fetuses were not adversely affected.

Abnormalities, Radiation-Induced↗
PubMed1984

In vitro effects of microwave radiation on rat liver mitochondria.

Liver mitochondria were exposed in vitro at 30 degrees C to microwave radiation (2.45 GHz) during the following states of respiration: resting, state 1; substrate dependent, state 2; ADP stimulated, state 3; and ADP depleted, state 4. At 10 or 100 mW/g, with succinate as substrate, no effect of exposure was observed on states 1-4 or the respiratory control index (state 3/state 4) of either tightly or loosely coupled mitochondria. When glutamate was used as substrate, no effects were observed at 10 mW/g. However, in the loosely coupled mitochondria the 100 mW/g exposure produced an increase in states 2 and 4 and a decrease in the respiratory control index. The results suggest that the function of loosely coupled mitochondria can be affected at high power levels of microwave radiation.

Animals↗
PubMed1984

Effect of 2450 MHz microwave radiation on hematopoiesis of pregnant mice.

In this study, the influence of 2450 MHz CW microwave radiation on hematopoiesis in pregnant mice was examined. Dams (mice CD-1 strain) were irradiated during Days 1-6 or 6-15 of pregnancy. The animals were irradiated for a total of 8 hr per day (two 4-hr exposures in 9 hr) at an average power density of 30 mW/cm2. Peripheral blood and bone marrow samples were obtained on Day 18 of pregnancy. The total leukocyte and differential leukocyte counts of peripheral blood samples were not affected by either exposure regimen. In addition, no effects were noted in either the erythroid or myeloid mitotic indices of bone marrow samples. Exposure of pregnant mice to microwave radiation under the conditions of these experiments had no effects on the investigated aspects of hematopoiesis.

Animals↗
PubMed1983

Influence of in vitro microwave radiation on the fertilizing capacity of turkey sperm.

Turkey sperm were exposed to 2.45-GHz microwave radiation in a temperature-controlled wave-guide apparatus. Temperature was maintained at either 25 or 40.5 degrees C. The sperm were exposed for 30 min at a specific absorption rate (SAR) of 10 or 50 mW/g. Following irradiation, the sperm were used to inseminate virgin turkey hens artificially. During the 9 weeks following the single insemination, the following were assessed: mean number of eggs, percentage of fertile eggs, rate of decrease in egg fertility, percentage of hatched eggs, and percentage of early and late deaths. These data demonstrate that, for the conditions used in these experiments, microwave radiation has no effect on the fertilizing capacity of turkey sperm.

Animals↗
PubMed1983

Effect of 2,450 MHz microwave radiation on the development of the rat brain.

Male Sprague-Dawley rats were exposed to 2,450 MHz microwave radiation at an incident power density of 10 mW/cm2 daily for 3 hours from day 4 of pregnancy (in utero exposure) through day 40 postpartum, except for 2 days at the perinatal period. The animals were killed, and the brains removed, weighed, measured, and histologically examined at 15, 20, 30, and 40 days of age. The histologic parameters examined included the cortical architecture of the cerebral cortex, the decline of the germinal layer along the lateral ventricles, the myelination of the corpus callosum, and the decline of the external germinal layer of the cerebellar cortex. In 40-day-old rats, quantitative measurements of neurons were also made. The spine density of the pyramidal cells in layer III of the somatosensory cortex, and the density of basal dendritic trees of the pyramidal cells in layer V were measured in Golgi-Cox impregnated specimens. In addition, the density of Purkinje cells and the extent of the Purkinje cell layer in each lobule were measured in midsagittal sections of the cerebellum stained with thionin. There were no remarkable differences between microwave-exposed and control (sham-irradiated) groups for any of the histologic or quantitative parameters examined; however, the findings provide important information on quantitative measurements of the brain. The data from this study failed to demonstrate that there is a significant effect on rat brain development due to microwave exposure (10 mW/cm2) during the embryonic, fetal, and postnatal periods.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

Effects of 2450 MHz microwave radiation during the gestational period on the postnatal hematology of rats.

Pregnant Sprague-Dawley rats were exposed to 2.45 GHz CW radiation for 3 h daily from day 4 through day 20 of pregnancy at an average power density of 10.3 mW/cm2. At 2, 10, 20, and 30 d postpartum, several aspects of peripheral blood hematology of male and female pups were examined. No effects were noted on pregnancy rate or litter size; however, pup weight was reduced. Also, the white blood cell numbers were lower in male and female pups exposed to microwave radiation and the differential cell counts were altered in the female pups at 10 d postpartum. At 30 d of age, no differences were noted between the sham and exposed pups for any of the hematologic variables examined.

Animals↗