Two thousand two-hundred and thirty-three deciduous teeth were collected from cities, industrialized areas, and rural and fishing communities in several Norwegian counties. Teeth from Medieval Bergen were also included. Lead analysis of whole teeth revelant that in Norway there are many communities where lead absorption is minimal and comparable to background absorption in ancient societies. Such conditions are reflected in a lead level of 2.92 microgram/g in deciduous teeth. However, the analysis also revealed that urbaization and industrialization increased lead absorption, although the mean level recorded in Norway of 3.73 microgram/g was far lower than normal levels found in other countries. Automobile exhaust was rejected as an important source of undue lead absorption. This study indicated that 0.18% of Norwegian children from the ages of 7 to 12 yr may have been victims of undue absorption, reflected in a tooth lead level of about 70 microgram/g.
– Incisal dentin of mandible cow incisors was studied by incident light. The material consisted of 12 intact permanent unerupted incisors from 2‐yr‐old cows removed immediately after bleeding. These specimens were kept in an isotonic EDTA‐sucrose solution to be decalcified while maintaining vitality of cellular components. Three of the specimens were successfully dissected in a mesiodistal plane, exposing the giant tubule lumens and their content. By the use of NBT, a compound reduced by the dehydrogenase enzymes of the electron transport in the inner mitochondrial membrane, it was concluded that the giant tubules contained vital cells. The giant tubules were also shown to communicate with the incisal part of the pulp cavity by wide openings.
The localization and concentration of copper in cryostat sections of human fallopian tubes from women using an intrauterine contraceptive device (IUCD) and controls was determined by light microscopic- and atomic absorption spectrophotometric techniques. The copper was visually accumulated in the epithelium and the copper concentration in the tubal tissue was increased in the IUCD user group. We also measured the concentration of copper and ceruloplasmin in serum, but there was no statistical difference between the two groups studied. Our results indicate that the IUCD has effects beyond the uterine cavity. The accumulation of copper may be associated with earlier observations of the morphological changes and infiltration of inflammatory cells observed in the fallopian tube in IUCD users.
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