Functional analysis of chimpanzee (Pan troglodytes) private signing

The chimpanzee's use of American Sign Language (ASL) to communicate with humans and with each other has been empirically demonstrated in several reports, but this is the first research to experimentally examine their use of sign language in a nonsocial fashion: private signing. This experiment examined the private signing behavior of five signing chimpanzees, using a remote videotaping technique with no human present. It was found that all five chimpanzees signed to themselves for a total of 368 instances. These instances of private signing were classified into nine different functional categories as has been done in the analysis of private speech and signing in hearing and deaf human children. Similar to humans, a few of the categories accounted for the majority of the instances of private signing. These findings empirically demonstrate a behavior similar to private speech and signing in humans.     

Transductional mapping of ksgB and a new Tn5-induced kasugamycin resistance gene, ksgD, in Escherichia coli K-12

We have mapped the Escherichia coli ksgB gene to min 36.5, 0.8 min from man and 0.7 min from aroD. A new kasugamycin resistance (Ksgr) gene, ksgD, has been isolated, using a transposon, Tn5. ksgD::TN5 is 44% cotransducible with sbcA, unlinked to trp, and unlinked to man (by P1 transduction). The ksgD::Tn5 has a late time of entry from HfrB7 (PO43). These data place ksgD clockwise from sbcA (which enters early from HfrB7) at min 30.4. The reistance of ksgB ksgD single and double mutant strains has been quantitated. Single mutations, ksgB or ksgD, gave resistance to 600 micrograms of kasugamycin per ml, whereas a ksgB ksgD strain was able to grow in the presence of kasugamycin levels in excess of 3,000 micrograms/ml. This indicates that the mechanisms of resistance coded for by the two genes are independent and synergistic.     

Imaginary Play in chimpanzees (Pan troglodytes)

Imaginary Play was studied in a group of five signing chimpanzees and it was found that chimpanzees engage in imaginary play similar to that found in human children. Fifteen hours of remote videotapes were analyzed for instances of imaginary play. Behaviors were defined as imaginary play by meeting a predetermined criteria which allowed them to be classified into one of six different categories of imaginary play. Six instances of imaginary play were found and these were classified into the two categories of Animation and Substitution. Observations of imaginary play in other research with chimpanzees were discussed.     

Activation of the mitogen-activated protein kinase signaling pathway is instrumental in determining the ability of Mycobacterium avium to grow in murine macrophages.

Of the two common morphotypes of Mycobacterium avium, designated smooth transparent (SmT) or smooth opaque (SmO), the SmO morphotype is avirulent, whereas the SmT morphotype is virulent. The role of the host macrophage in determining these different virulence phenotypes was analyzed using an in vitro model of macrophage infection. Initial studies confirmed previous reports of the increased ability of the SmT bacteria to grow in macrophages; this increased virulence correlated with reduced induction of inflammatory cytokines. Examination of the response of the mitogen-activated protein kinase (MAPK) pathway following infection with either morphotype revealed that all three members of the MAPK pathway were activated. Pharmacologic inhibition of either the extracellular signal-regulated kinase (ERK) or p38(MAPK) pathways resulted in distinct consequences for the growth of the two morphotypes. In particular, inhibition of the p38(MAPK) resulted in attenuated growth of the SmT morphotype, which correlated with reduced PGE(2) production. Inhibition of cyclooxygenase 2 by indomethacin also inhibited growth of SmT, substantiating the role for PGE(2) in promoting the growth of SmT. In contrast, SmO induction of the ERK pathway was increased compared with the SmT morphotype, and inhibition of ERK resulted in decreased TNF-alpha synthesis and enhanced SmO growth. Pharmacologic inhibitors of the MAPK pathway were present for only the first 4 h of infection and yet had consequences for bacterial growth at 7 days. Therefore, the data suggest that induction of the MAPK pathway during uptake of bacteria is instrumental in determining the eventual fate of the bacteria.