MODIFICATION OF THE NORTHROP-KUNITZ MICROCATAPHORESIS CELL

A modification of the Northrop-Kunitz microcataphoresis cell is described. Although the theory of von Smoluchowski relating to such systems is in general followed, certain deviations may be encountered which are easily avoided.     

Nephrogenous cyclic adenosine monophosphate levels in normocalcemic cancer patients: its significance

We evaluated nephrogenous cyclic adenosine monophosphate ( NcAMP ) levels in 61 normocalcemic patients with documented cancer of various organs and cell types. NcAMP levels were elevated in 17 (28%) and decreased in 13 (21%) of the cancer patients. Both high and low NcAMP levels were seen within the various cancer groups. There was a significant correlation (r = 0.383, P less than 0.01) between NcAMP and serum parathyroid hormone (PTH) levels, suggesting that tumor-related factors affecting NcAMP , may be partially related to native PTH. Alternatively, these factors might be altering the effect of endogenous PTH on renal tubules. A significant negative correlation was also observed between NcAMP and tubular maximum for phosphate (r = -0.356, P less than 0.02) suggesting that either cAMP per se or factors affecting NcAMP alter phosphate excretion. Follow up serum calcium data was available on 48 of the 61 patients. Subsequent hypercalcemia developed independent of the initial nephrogenous cAMP levels. It therefore appears that NcAMP elevation and development of hypercalcemia are two separate paraneoplastic phenomena.     

Relationship between suicide and myocardial infarction with regard to changing physical environmental conditions

In recent years, the possible association of changes in mortality from cardiovascular disease and myocardial infarction (MI) and deaths related to violence and the suicide rate has been repeatedly discussed. This study examined the relationship between cosmic physical changes (solar, geomagnetic and other space activity parameters) and changes in the total number of in-hospital and MI-related deaths and deaths from suicide to determine if a relationship exists between the distribution of total and MI-related deaths with suicide over time; some differences in the serotonergic mechanisms involved in the pathogenesis of MI and suicide were also taken into account. All suicides (n=2359) registered in the State of Israel from 1981 to 1989 (108 months) were analysed and compared with the total number of deaths (n=15601) and deaths from MI (n=1573) in a large university hospital over 180 months (1974–1989). The following were the main features of the Results. (1) Monthly suicide rate was correlated with space proton flux (r=0.42,P=0.0001) and with geomagnetic activity (r=–0.22,P=0.03). (2) Total hospital and MI-related deaths were correlated with solar activity parameters (r=0.35,P<0.001) and radiowave propagation (r=0.52-0.44,P<0.001), an with proton flux (r=–0.3 to –0.26,P<0.01). (3) Monthly suicide distribution over 108 months was correlated with MI (r=–0.33,P=0.0005) and total hospital mortality (r=–0.22,P=0.024). (4) Gender differences were prominent. We conclude that the monthly distributions of suicides and deaths from MI are adversely related to many environmental physical parameters and negatively correlated with each other.     

Human and animal leptospirosis in irrigated lands

To study the influence of amelioration on the spread of leptospirosis, the survey of humans, agricultural animals and rodent was made on the territory where the irrigation system was under construction and during 2 years after the beginning of irrigation. This survey failed to establish the occurrence of significant changes in the number of rodents and their species composition, as well as in the number of agricultural animals showing the positive reaction to leptospirosis. No cases of leptospirosis were registered, and during the first years after the beginning of irrigation antibodies in low titers were detected only in 4 out of 536 subjects. The results obtained in this survey suggest that during the first years of artificial irrigation the conditions for a wider spread of leptospirosis do not appear, but the final solution of this problem can be made on the basis of observations lasting for many years.     

Use of Flower Color-Cue Memory by Honey Bee Foragers Continues when Rewards No Longer Differ between Flower Colors

Honey bees (Hymenoptera: Apidae) were used as a model insect system to explore forager use of a learned color-cue memory over several subsequent days. Experiments used artificial flower patches of blue and white flowers. Two experiments were performed, each beginning with a learning experience where 2 M sucrose was present in one flower color and 1 M sucrose in the alternative flower color. The first experiment followed flower color fidelity over a series of sequential days when rewards no longer differed between flowers of different color. The second examined the effect of intervening days without the forager visiting the flower patch. Results showed that color-cue memory decline was not a passive time-decay process and that information update in honey bees does not occur readily without new experiences of difference in rewarding flowers. Further, although the color cue learned was associated with nectar reward in long term memory, it did not seem to be specifically associated with the 2 M sucrose nectar reward when intervening nights occurred between learning and revisiting the flower patch.     

Evolutionary trends in the dentition of true lemmings (Lemmini, Cricetidae, Rodentia): functional-adaptive analysis

This paper offers a functional analysis of structure and variation trends in the dentition of species of the tribe Lemmini Simpson, 1945. The striking differences in the structure, trends in variation and rate of evolution between the Lemmini and all other members of Arvicolinae can be understood from the quite different functioning of the masticatory apparatus. The polarity of character states in the dentition of the Lemmini is discussed. Suggested polarity is supported by the palaeontological and functional evidence. The distinctive means of increasing the efficiency of the masticatory apparatus seen in Lemmini not only reflects definite genetic history but can also be explained by their very unusual food specialization and the demands it imposes on the mechanics of their masticatory apparatus.