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Biomedical subjects

G Linden

Publications and source records attributed to G Linden.

At least 55 records · Page 3Linked to original sources
PubMed1975

Mitochondrial and cytoplasmic ribosomes and their activity in blood and culture form Trypanosoma brucei.

Ribosomes of Trypanosoma brucei, a parasitic, flagellated protozoan (order Kinetoplastida), were identified on sucrose density gradients by their radioactively labeled nascent peptides. Ultraviolet absorption revealed only cytoplasmic ribosomes which served as internal sedimentation markers. Synthesis on cytoplasmic ribosomes was completely inhibited by cycloheximide. In the presence of this antibiotic, nascent peptides were associated with ribosomes of lower sedimentation coefficient than the cytoplasmic ribosomes. Chloramphenicol blocked synthesis on these ribosomes which are probably the mitochondrial ribosomes. These ribosomes differed from the cytoplasmic ribosomes in several ways. Their sedimentation coefficient was about 72S rather than 84S. The stability of the 72S ribosomes was less sensitive to pancreatic ribonuclease and low Mg-++ concentrations, dissociating below 0.1 mM Mg++. The 72S ribosomes were more sensitive to elevated KCl concentrations, dissociation above 0.25 M. Protein synthetic activity associated with the 72S class of ribosomes was found in trypanosomes grown in rats. Under these conditions no cytochromes or fully active Krebs cycle is present in these cells and respiration is insensitive to cyanide.

Animals↗
PubMed1972

Cancer patterns in Alameda County, California.

There has been a general increase in the incidence of cancer of most major sites during the period 1960-69; this is true even when allowances are made for shifts in the age composition of the population. Improvements in diagnostic procedures may account for some of these increases but it is doubtful that they are solely responsible for the greater incidence recorded.A few sites stand out as being primarily responsible for the increase in the overall cancer incidence. Lung cancer is increasing in both males and females; the rate of increase, however, is much greater among females. It is generally acknowledged that women began smoking cigarettes at a later point in time and to a lesser extent. The pattern which has emerged indicates that females are experiencing a similar trend in lung cancer incidence to that of males. The increase in the incidence of female breast cancer is also noteworthy, although the forces producing this change can only be speculated upon. The high incidence of prostatic cancer among negroes and the increase in the incidence of prostatic cancer in whites are subjects which deserve further investigation, especially since the Alameda County experience is not duplicated in data from the Connecticut Tumour Registry. One of the most encouraging findings is that the incidence of stomach cancer appears to be declining.

Black or African American↗