Although Ni uptake was variable, it was generally low, whereas Co uptake was substantial, as had previously been observed in the same plant when Co was the only binder under use. It was therefore possible to rule out any influence of Ni exposure on Co uptake and to suggest the contrary, as has been demonstrated in bacterial species and in rats using everted intestinal sacs.
Twenty-six workers in a hard metal manufacturing plant were monitored by cobalt urinary and ambient air measurements during the first month after summer holidays. Cobalt determinations were performed utilizing AAS, with a preliminary chelation and extraction procedure for urinary samples. Almost all personal ambient air samples turned out to be under the cobalt dust TLV of 0.1 mg/m3. When restarting work after the holidays, urinary values did not differ from the control group. At the end of the first working week, urinary cobalt had increased four fold, then decreased to the original values on the following Monday before restarting work. Thereafter, the weekend was no longer sufficient to reduce the levels to normal urinary cobalt values. The values rose to the same level observed before the holidays, and dit not substantially decrease even after the weekend. End-shift urinary cobalt values showed a good relationship with present as well as with mean past exposure on the first and the fifth weekday, but the third day did not. The correlation was better with present exposure on Monday and with mean past exposure on Friday. The observed differences may be explained by the minor influence of recent exposure on present exposure on Monday. The highest values were found on Wednesday. We suggest the utilization of end-shift urinary cobalt determination as a measure of the present exposure on Monday, and of mean recent or preceding exposure on Friday.
A case of juvenile secretory carcinoma of the breast is reported. The tumor occurred in a 19 yr-old nulliparous woman and was treated by local resection; it recurred 7 years later. Slight infiltration of the pectoral muscle, metastatic involvement of one lymph node and multifocal areas of carcinoma were found at radical mastectomy. No further recurrence has been detected after 1 year. This case confirms the slow evolution of this neoplasm but stresses that its behavior is not always as indolent as previously believed. We have used histochemical techniques for mucins (PAS, Alcian Blue) and immunoperoxidase methods for milk proteins (MFGM, beta-Casein, alpha-lactalbumin), for myoepithelial cells (actin) and for oncofetal antigens (CEA). Our results suggest that: Immunoperoxidase methods for milk proteins are a more specific and reliable marker than PAS staining in characterizing the secretory activity of juvenile carcinoma. The absence of myoepithelial cells in infiltrative areas detected by immunoperoxidase methods for actin confirms the low degree of organization in this well differentiated carcinoma of limited aggressiveness which secretes milk proteins.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.