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At least 1,153 records · Page 64Linked to original sources
PubMed1994

A new coccidian (Apicomplexa: eimeriidae) in the northern pocket gopher (Thomomys talpoides) and a comparison of oocyst survival in hosts from radon-rich and radon-poor soils.

Forty (93%) of 43 northern pocket gophers (Thomomys talpoides) from the Jemez Mountains, Sandoval County, New Mexico (USA), had coccidian oocysts in their feces when examined. We describe this parasite, Eimeria jemezi, n. sp. Sporulated oocysts were subspheroidal, 13.3 by 12.2 (10 to 17 by 9 to 15) microns, with sporocysts ellipsoidal, 7.1 by 4.4 (5 to 9 by 4 to 5) microns; micropyle and oocyst residuum were absent, but polar bodies, Stieda bodies and sporocyst residua were present. All gophers were collected from two sites of similar habitat 7 km apart. One site (R+) had a high soil radon content (> or = 50 to 70 picocuries (pCi) per liter of air) whereas the other site (R-) had soils that were near average natural levels (1.2 to 1.6 pCi/g uranium nucleotides per gram of soil; < 1.9 pCi/g thorium nucleotides). Twenty-one (88%) of 24 gophers from the R+ site had coccidian oocysts in their intestines when examined, but none of these oocysts ever sporulated, whereas all 19 (100%) gophers from the R- site had coccidian oocysts in their intestines and 16 (84%) of these samples sporulated normally under laboratory conditions. The elevated radon content of the soil may have had an adverse effect on the sporulation of this coccidian while it still was intracellular within its host.

Animals↗
PubMed1998

Primary hepatic angiosarcoma: report of a case involving environmental arsenic exposure.

Hepatic angiosarcoma is a rare malignant tumor with a rapidly fatal course. It has become a subject of interest because of its intimate relationship with environmental carcinogens, such as thorium dioxide (Thorotrast), vinyl chloride monomer, and arsenic. We describe a case of a chronic hepatitis B surface antigen carrier, with a 20-year history of environmental exposure to arsenical-containing agricultural herbicides and bactericides, who developed a hepatic angiosarcoma. He died due to rupture of the hepatic angiosarcoma with acute hemoperitoneum 9 weeks after initial diagnosis. This is a rare case of primary hepatic sarcoma, especially in Taiwan where hepatocellular carcinoma is endemic. This case not only serves to give more evidence of the relationship between hepatic angiosarcoma and arsenical exposure, but also demonstrates the key point in the differential diagnosis of liver tumors. Increased familiarity with this disease will facilitate correct diagnosis and help to improve management of the condition in the future.

Agriculture↗
PubMed1999

Population study in the high natural background radiation area in Kerala, India.

A comprehensive survey of the population exposed to high-level natural radiation is presented. The population living in Karunagappally taluk in Kerala, India, presents a unique opportunity for studies on the health effects of chronic exposure to low-level radiation. The environmental radiation emanates largely from the thorium deposited mostly along coastal areas. In certain locations on the coast, it is as high as 70 mGy/year and on average is 7.5 times the level seen in interior areas. Using portable scintillometers, radiation levels in more than 66,306 houses were measured; outside levels were also measured in the same house compound. Of the total population of 400,000, 100,000 lived in areas with high natural radiation. Information on lifestyle, socio-demographic features, occupation, housing, residence history, and tobacco and alcohol use was obtained by house-to-house visits and enumeration of every resident individual. A population cancer registry system has been established to obtain cancer incidence rates. In this preliminary analysis, there is no evidence that cancer occurrence is consistently higher because of the levels of external gamma-radiation exposure in the area. Further dosimetry-level studies are needed along with biological studies. Studies of soil, thoron-in-breath, and the radon-thoron levels in houses are ongoing, and further case-control analyses are continuing.

Adolescent↗
PubMed1999

Radium and radon in natural underground water supply in the region of Lódź, Poland.

The region of Lódź, located in the central part of Poland, is very specific with respect to water supply coverage. In this densly populated and extensively industrialised region there is a lack of natural reservoirs of surface water in the nearest vicinity of Lódź. Therefore, over 50% of water for public and domestic use is provided from underground water intakes. It is well known from the literature that in underground water may occur radionuclides in the uranium and thorium decay series. Underground water intakes in Lódź used for public water supplies have been surveyed for the presence of radium-226 and radon-222 since the earlier studies of quality standards of the gross alpha and gross beta activity pointed to their possible excessive values. The surveillance was based on the guidelines set by the World Health Organisation (WHO). The measurements of radium-226 activity showed its different concentrations depending on the age of the water-bearing level. These concentrations fell within the range of < 10 divided by 50 Bqm-3. Measurements of radon yielded similar results and its highest concentrations were found in the Lower cretaceous and Jurassic formations. Radon concentrations ranged from 200 to 11,400 Bqm-3. A maximum annual dose taken into the body in the population drinking this water may account for 0.85 microSv which is lower than the limit recommended by WHO.

Carcinogens, Environmental↗
PubMed2000

Anomalous X-ray diffraction with soft X-ray synchrotron radiation.

Anomalous diffraction with soft X-ray synchrotron radiation opens new possibilities in protein crystallography and materials science. Low-Z elements like silicon, phosphorus, sulfur and chlorine become accessible as new labels in structural studies. Some of the heavy elements like uranium exhibit an unusually strong dispersion at their M(V) absorption edge (lambdaMV = 3.497 A, E(MV) = 3545 eV) and so does thorium. Two different test experiments are reported here showing the feasibility of anomalous X-ray diffraction at long wavelengths with a protein containing uranium and with a salt containing chlorine atoms. With 110 electrons the anomalous scattering amplitude of uranium exceeds by a factor of 4 the resonance scattering of other strong anomalous scatterers like that of the lanthanides at their L(III) edge. The resulting exceptional phasing power of uranium is most attractive in protein crystallography using the multi-wavelength anomalous diffraction (MAD) method. The anomalous dispersion of an uranium derivative of asparaginyl-tRNA synthetase (hexagonal unit cell; a = 123.4 A, c = 124.4 A) has been measured for the first time at 4 wavelengths near the M(V) edge using the beamline ID1 of ESRF (Grenoble, France). The present set up allowed to measure only 30% of the possible reflections at a resolution of 4 A, mainly because of the low sensitivity of the CCD detector. In the second experiment, the dispersion of the intensity of 5 X-ray diffraction peaks from pentakismethylammonium undecachlorodibismuthate (PMACB, orthorhombic unit cell; a = 13.003 A, b = 14.038 A, c = 15.450 A) has been measured at 30 wavelengths near the K absorption edge of chlorine (lambdaK = 4.397 A, EK= 2819.6 eV). All reflections within the resolution range from 6.4 A to 3.4 A expected in the 20 degree scan were observed. The chemical state varies between different chlorine atoms of PMACB, and so does the dispersion of different Bragg peaks near the K-edge of chlorine. The results reflect the performance of the beamline ID1 of ESRF at wavelengths beyond 3 A at the end of 1998. A gain by a factor 100 for diffraction experiments with 4.4 A photons was achieved in Autumn 1999 when two focusing mirrors had been added to the X-ray optics. Further progress is expected from area detectors more sensitive to soft X-rays. Both CCD detectors and image plates would provide a gain of two orders of measured intensity. Image plates would have the additional advantage that they can be bent cylindrically and thus cover a larger solid angle in reciprocal space. In many cases, samples need to be cooled: closed and open systems are presented. A comparison with the state of art of soft X-ray diffraction, as it had been reached at HASYLAB (Hamburg, Germany), and as it is developing at the Brookhaven National Laboratory (USA), is given.

Amino Acyl-tRNA Synthetases↗
PubMed1975

Identification of a novel cell type in peripheral lymphoid organs of mice. IV. Identification and distribution in mouse spleen.

White pulp nodules of mouse spleen contain a minor population of cells with morphologic features that are identical to those of dendritic cells, a cell type recently described in vitro. They have characteristic large, irregularly shaped nuclei with distinctive chromatin patterns and small nucleoli. The cytoplasm is extended in processes that contain relatively few organelles. These presumptive dendritic cells can be distinguished from other cell types that are known to exist in spleen including those that have irregular or branching cell shapes. In particular, dendritic cells do not contain the large number of lysosomes seen in phagocytes, and do not actively interiorize intravenously administered colloidal thorium dioxide particles. They also lack the well developed secretory apparatus (rough endoplasmic reticulum and Golgi zone) and microfilament bundles that are noted in connective tissue cells. These morphologic observations, combined with previous in vitro work, substantiate the existence of a novel class of cells in mouse lymphoid organs.

Animals↗
PubMed2001

Analytical microscopy observations of rat enterocytes after oral administration of soluble salts of lanthanides, actinides and elements of group III-A of the periodic chart.

The behavior in the intestinal barrier of nine elements (three of the group III-A, four lanthanides and two actinides), absorbed as soluble salts, has been studied by two microanalytical methods: electron probe X-ray micro analysis (EPMA) and secondary ion mass spectrometry (SIMS). It has been shown that the three elements of group III-A, aluminium, gallium and indium; and the four lanthanides, lanthanum, cerium, europium and thulium, are selectively concentrated and precipitated as non-soluble form in enterocytes of proximal part of the intestinal tract. SIMS microscopy has shown that these elements are concentrated as a number of submicroscopic precipitates, most of them localized in the apical part of the duodenum enterocytes, where they are observed from one hour to 48 hr after a single intragastric administration. No precipitate is observed after three days. It is suggested that this mechanism of local concentration limits the diffusion of these elements through the digestive barrier, some of them being toxic and none of them having a recognized physiological role. Additionally, the precipitation in duodenal enterocytes, the life time of which is on the order of 2-3 days, allows the elements absorbed as soluble form to be eliminated as a non-soluble form in the digestive lumen along with the desquamation of the apoptotic enterocytes. The intracytoplasmic localization of the precipitates are supposed to be the lysosomes although no direct evidence could be given here due to the very small sizes of the lysosomes of enterocytes. The same results were not observed with the two studied actinides. After administration of thorium, only some very sparse microprecipitates could be observed in intestinal mucosa and, after administration of uranium, no precipitates were observed with the exception of some in the conjunctive part of the duodenal villi.

Actinoid Series Elements↗
PubMed1999

Dr. Nobuo Yamada's whole life, dead due to his radioactive studies at the Radium Institute (Part 2): in celebration of the 100-year anniversary of the discovering radium, 1898-1998.

On the occasion of the 100th anniversary of the discovery of radium by M. & Mme. Curie, commemorative lecture meetings were held in Japan in 1998 as follows. 1) The 42nd Symposium on Radiochemistry was held in Sendai on September 18. Dr. M. Sakanoue, Professor Emeritus Kanazawa University, presented a commemorative lecture entitled "Collaborative Research done by Irene Curie and Nobuo Yamada." He explained an outline of the studies on the measurement of long-range particles emitted by various radioactive substances such as polonium, radium and thorium. In addition to his lecture, I made a comment on the curriculum vitae of Dr. N. Yamada. 2) On October 24, another commemorative lecture meeting was held in Tokyo. At this meeting, Helene Langevin-Joliot, daughter of Irene Joliot-Curie presented a lecture on whole life of M. & Mme. Curie as a guest speaker. After meeting ended, I had the opportunity to talk with her personally. I have been investigating references describing the cause of death of Dr. Nobuo Yamada and found the following. The inadequacy of an apparatus for protection from radioactivity in the 1920s and reference to the death of Dr. Nobuo Yamada specifically were described in an article written by Dr. S. Iimori and in a nonograph written by Dr. M. Furukawa. The tragedy of scientists who suffered severe radiation syndrome during experiments at the Radium Institute was described in a biography of Marie Curie written by Susan Quinn.

Academies and Institutes↗
PubMed1975

[Liver disease in polyvinyl chloride production workers - Clinical and peritoneoscopic aspects (author's transl)].

Peculiar clinical symptoms observed in polyvinyl chloride production workers of a nearby chemical plant arose the suspicion of liver and spleen disease in these workers before first reports on vinyl chloride-induced angiosarcoma of the liver became known. Starting at the end of 1972, 44 workers were followed up by biochemical investigations, peritoneoscopy and liver biopsy. As early as 1973 it could be ascertained, that advanced vinyl chloride-induced liver damage presents as hepatic fibrosis with splenomegaly, portal hypertension, and thrombocytopenia without conspicuous deterioration of hepatic parenchyma function. Similar symptoms have been observed after chronic intoxication by arsenic and thorium dioxide (thorotrast). The clinical and peritoneoscopic aspects of the disease are described.

Chemical Industry↗
PubMed1975

Bronchial deposition of free ions and submicron particles studied in excised lung.

Direct measurements of bronchial deposition in ventilated pig lungs are reported for radon daughter ions and condensation nuclei. Comparisons are made with deposition calculated from the theory of particle diffusion in steady, laminar air-flow. In segmental bronchi, the observed deposition of condensation nuclei was within about 25% of that calculated. Deposition was greater by up to a factor 2 in main stem and lobar bronchi. Deposition in the trachea depended upon the entrance conditions set by vocal cords. For thorium-B ions, deposition in segmental bronchi was a factor 4 less than calculated, apparently due to rapid hygroscopic growth. Clearance rates by dissolution from bronchial epithelium in vivo for lead and bismuth ions are also reported. Approximately 10% of 212Pb ions diffused into blood with a half-time of about 70 min and 30% of 212Bi ions with a much shorter half-time of about 7 min. The implications of these data in the calculation of radiation dose from inhaled radon daughters are discussed.

Aerosols↗
PubMed2002

Study in China on ingestion and organ content of trace elements of importance in radiological protection.

To improve knowledge of the ingestion and organ content of calcium, cesium, iodine, potassium, strontium, thorium, and uranium that have a high priority in radiological protection, a total diet and organ content studies was conducted. The total diet study used the market basket sample method with representative sampling. For the organ content specimens of muscle, skeleton, liver, kidney, lung, and thyroid were collected during autopsies of normal, healthy adult accidental death victims. The concentration of above stated elements in the diet and organs were analyzed by nuclear and nuclear-related techniques with strict quality assurance measures. The results are presented in the paper and compared with previous national and international data and the parameters of current International Commission on Radiological Protection (ICRP) Reference Man. The study provided a new and reliable database for setting the parameters for the Chinese reference man and the reference Asian man. It also facilitated the study on biokinetics behavior of their radiation counterparts in human body and helped in the realistic assessment of their internal radiation doses.

Body Composition↗
PubMed2002

[Archaeological application of the Raman microprobe to the non-destructive identification of dinosaur fossil from Yunnan Wuding].

Selected ancient Dinosaur fossils (about a hundred million ago) from Wuding, Yunnan, pilot were studied by micro-Raman spectroscopy, atomic emissive spectrum and polarization microscopic analysis. Raman experimental results found out the primary compounds of fossil surface and section are calcite (CaCO3), and are not others. Analysis of atomic emissive spectrum indicated that main elements of fossils are calcium (> 10%), silicon (5.0%), phosphor (4.0%) and iron (1.0%), rare elements example of iridium (Ir) and thorium (Th) are not found in testing. Complementary studies by atomic emissive spectrum and polarization microscope found that besides calcite (CaCO3), SiO2.nH2O, which is not crystal, is contained in the examples of the fossils. Main composition data taken from both the atomic emissive spectrum, microscopic photograph and Raman spectroscopy are in agreement.

English Abstract↗
PubMed2003

[Angiosarcoma (hemangiosarcoma) cordis].

The case of a young 32 year old male with a primary cardiac angiosarcoma is reported. The neoplasm manifested itself by a quickly increasing cardiac tamponade but without metastases. The nonradical resection of the tumor was made because of local invasion with tumor tissue. The patient was followed-up for 3 years after the surgery and no recurrence of the malignant process was observed. Cardiac angiosarcoma is a very rare malignant tumor of soft tissues. In spite of significant progress in clinical treatment, for a patient diagnosed antemortem with cardiac angiosarcoma, the long-term expectations are usually very poor. Commonly known risk factors for this group of neoplasms (haemangioma of skin, chroniclymphedema, chronic post-tuberculosis pleurisy, X-ray, thorium dioxide) cannot be easily associated with the primary cardiac angiosarcoma cases. The search for chromosomal anomalies and gene mutations leading to cardiac angiosarcoma is ongoing. There is hope that recently obtained evidence for mutation of the p53gen, will provide a better understanding of this heart neoplasia.

Adult↗
PubMed2004

Trace elements in Jamaican tobacco.

The concentrations of 28 elements, in hand-made cigars, "rope" tobacco and freshly picked tobacco leaves from the parish of Manchester in central Jamaica, were compared with locally packaged and imported cigarettes and cigars. Except for chromium and vanadium, which are lower in the imported products, the elemental concentrations of all the brands sold in Jamaica are rather similar. The means for aluminium, cadmium, caesium, cerium, chromium, iron, thorium, uranium, vanadium and zinc for the Manchester material exceed the maximum values of the other tobaccos. The significant concentrations of heavy metals, and especially cadmium, which is about 50 times that of commercial cigarettes, reflect the known high concentrations in the soils in the region. This tobacco is not filtered and the smoke contains 50% of the cadmium. This, and the concentrations of radioactive elements, may indicate an additional health risk compared with commercial cigarettes. A study of three samples of marijuana indicates a similar level of risk from heavy metals.

Cannabis↗
PubMedDate not supplied

Pioneers of nuclear medicine, Madame Curie.

Among those who have made important discoveries in the field of radioactivity and thus helped in the development of nuclear medicine as an identical entity are: Heinrich Hertz who in 1886 demonstrated the existence of radiowaves. In 1895 Wilhelm Röntgen discovered the X-rays. In 1896 H. Becquerel described the phenomenon of radioactivity. He showed that a radioactive uranium salt was emitting radioactivity which passing through a metal foil darkened a photographic plate. An analogous experiment performed by S.Thomson in London was announced to the president of the Royal Society of London before the time H.Becquerel announced his discovery but Thomson never claimed priority for his discovery. Muarie Sklodowska Curie (1867-1934) was undoubtedly the most important person to attribute to the discovery of radioactivity. In 1898 she discovered radium as a natural radioactive element. This is how she describes the hard time she had, working with her husband Pierre Curie (1859-1906) for the discovery of radium and polonium: "During the first year we did not go to the theater or to a concert or visited friends. I miss my relatives, my father and my daughter that I see every morning and only for a little while. But I do not complain...". In presenting her discovery of radium, Madame Curie said: " ...in the hands of a criminal, radium is very dangerous. So we must often ask ourselves: will humanity earn or lose from this discovery? I, myself belong to those who believe the former...". The notebooks that Madame Curie had when she was working with radium and other radioactive elements like polonium, thorium and uranium are now kept in Paris. They are contaminated with radioactive materials having very long half-lives and for this reason anyone who wishes to have access to these notes should sign that he takes full responsibility. There are some more interesting points in Madame Curie's life which may not be widely known like: Although her full name is Maria Sklodowska-Curie, she is not known neither by that full name nor as Maria Sklodowska but as Marie Curie. Madame Curie was the second of five children. At the age of 24 she went to Sorbonne-Paris after being invited by her sister Bronja to study for about 2-3 years; instead she stayed in Paris for her whole life. Her doctorate was on the subject: "Research on radioactive substances" which she completed in six years under the supervision of H. Becquerel. Pierre Curie was Director of the Physics Laboratory of the Ecole Municipale of Physics and Industrial Chemistry when he married M. Curie in 1895. Pierre Curie left his other research projects and worked full time with his wife. In this laboratory M. Curie and her husband Pierre discovered radium and polonium. In 1901 Pierre Curie induced a radiation burn on his forearm by applying on his skin radiferous barium chloride for 10 hours. During World War I, M.Curie organized for the Red Cross a fleet of radiological ambulances each with X-ray apparates which were called "Little Curies". The X-ray tubes of these apparates were unshielded and so M.Curie was exposed to high doses of radiation. Once an ambulance fell into a ditch and M.Curie who was inside the ambulance was badly bruised and stayed at home for 3 days. M. Curie with her daughters, Irene and Eve, was invited and visited America in 1921. She led a successful campaign to collect radium for her experiments. Before leaving America, President Harding donated through her to the Radium Institute of Paris 1 g of radium for research purposes. At that time the process to obtain 0.5 g of pure radium bromide required 1 ton of ore and 5 tons of chemicals. No measures of radiation protection were taken back then. In 1929 Madame Curie visited the United States for a second time. She met with President Hoover and with the help of the Polish women's association in America collected funds for another gram of radium. Madame Curie died of leukemia on July 4, 1934. Sixty years after her death her remnants were laid to rest under the dome of the Pantheon. Thus she became the first woman under her own merit, to rest in the Pantheon. In 1934 at the Institute of Radiology in Paris, Frederique Joliot and Irene Curie-Joliot discovered artificial radiation. They studied alpha particles and beta;-radiation.

Editorial↗
PubMed1965

An experimental obliterating thromboangiitis limited to the posterior part of the body.

After a brief outline of the principles involved in the production of thrombohemorrhagic phenomena (THP) with special organotropic localizations, an experimental technique is described which permits the production of acrocyanosis and thrombohemorrhagic lesions largely limited to the posterior part of the body. This phenomenon can be consistently produced by certain combinations of THP elicitors, anaphylactoid agents and noradrenaline (NA). The most effective combination among those tested is thorium dextrin (Th-Din) plus tannic acid plus NA. Several drugs can decisively influence the course of this reaction. Most otable among these are Neo-Antergan (an antihistaminic) which sensitizes for the production of the aboral THP, while heparin (presumably through its anticoagulant effect) and Dibenamine (presumably through its antiadrenergic action) offer virtually complete protection. When only Th-Din plus tannic acid is given, there develops an intense but reversible cyanosis in the hind paws and tail; additional treatment with NA induces obliterating thromboangiitis with hemorrhages and gangrene. None of hese changes are produced by Th-Din, tannic acid or NA alone. Evidently, here, e are dealing with pluricausal experimental diseases whose possible relationship to Raynaud's disease, thromboangiitis obliterans and anaphylactoid purpura is briefly discussed.

Animals↗
PubMed2006

[Radioactive waste due to electric power and mineral fertiliser production].

Radiation Protection Unit of the Institute for Medical Research and Occupational Health in Zagreb has been conducting systematic investigations of radioactive contamination of the Croatian environment by anthropogenic fission products as well as by naturally occurring radioactive material (NORM) since 1963. Several critical sites in Croatia were identified for NORM, that is, for slag and ash repositories from coal-fired power plants and phosphogypsum repository from a mineral fertilizer production plant. As the coals and phosphate ores contain naturally occurring radionuclides, especially the members of the uranium and thorium radioactive chains, utilising these materials in various industries only enhances their natural radioactivity in residual waste. Consequently, the resulting activity concentrations of natural radionuclides in waste material could be several times higher than in the adjacent soil. These deposited materials pose permanent risk of radiation exposure due to the long physical half-life of natural radionuclides (e.g., T 1/2 = 1600 years for 226Ra). Results of scientific investigations related to natural radioactivity are used in the recovery of slag and ash repositories and landfills, as well as in establishing regulatory criteria targeting import of coal and phosphate ores. In consequence, recently measured activity concentrations of natural radioactivity in imported materials used nowadays in coal-fired power plants are significantly lower than in previously used raw materials. Therefore, slag and ash can be used as additive materials in cement production.

Croatia↗