Satellite remote sensing,biodiversity research and conservation of the future

Assessing and predicting ecosystem responses to global environmental change and its impacts on human well-being are high priority targets for the scientific community. The potential for synergies between remote sensing science and ecology, especially satellite remote sensing and conservation biology, has been highlighted by many in the past. Yet, the two research communities have only recently begun to coordinate their agendas. Such synchronization is the key to improving the potential for satellite data effectively to support future environmental management decision-making processes. With this themed issue, we aim to illustrate how integrating remote sensing into ecological research promotes a better understanding of the mechanisms shaping current changes in biodiversity patterns and improves conservation efforts. Added benefits include fostering innovation, generating new research directions in both disciplines and the development of new satellite remote sensing products.     

Identification of an S-locus glycoprotein allele introgressed from B. napus ssp. rapifera to B. napus ssp. oleifera.

We have previously described a developmentally regulated mRNA in maize that accumulates in mature embryos and is involved in a variety of stress responses in the plant. The sequence of the encoded 16 kDa protein (MA16) predicts that it is an RNA-binding protein, since it possesses a ribonucleoprotein consensus sequence-type RNA-binding domain (CS-RBD). To assess the predicted RNA binding property of the protein and as a starting point to characterize its function we have used ribohomopolymer-binding assays. Here we show that the MA16-encoded protein binds preferentially to uridine- and guanosine-rich RNAs. In light of these results a likely role for this protein in RNA metabolism during late embryogenesis and in the stress response is discussed.     

Effect of tetranitromethane on the biological activities of botulinum neurotoxin types A,B and E

Botulinum neurotoxin serotypes A, B and E were modified at pH 7.9 with tetranitromethane, a reagent highly specific for tyrosine residues. The type B and E neurotoxins were completely detoxified without significant damage to their serological activities. Under similar modification conditions, the type A neurotoxin was incompletely detoxified with some alteration in its serological reactivity. Modification of only tyrosine residues to nitrotyrosine was evident from amino acid analysis of the acid hydrolysates of the modified proteins. The completely detoxified type B and E neurotoxins, used as toxoid, elicited antibodies in rabbits. The antisera precipitated and neutralized the homologous neurotoxin. The two toxoids, type B and E, were prepared with >99% pure neurotoxins as tested by sodium dodecyl sulfate-polyacrylamide gel electrophoresis whereas the traditional toxoids produced with formaldehyde are very crude preparations of the neurotoxin ( 90% impure). Chemical modification using tetranitromethane is more specific than products that form during 7 days of reaction between a protein and formaldehyde. The toxoids produced with tetranitromethane may be considered second-generation toxoids, compared with the first-generation toxoids (crude preparation of neurotoxins detoxified with formaldehyde).     

Parasites of prairie rattlesnakes (Crotalus viridis viridis) and gopher snakes (Pituophis melanoleucus sayi) from the eastern high plains of New Mexico

Three prairie rattlesnakes (Crotalus viridis viridis) and two gopher snakes (Pituophis melanoleucus sayi) from the eastern high plains of New Mexico (USA) were examined for parasites. One cestode (Oochoristica osheroffi), and two nematode (Kalicephalus inermis and Physoloptera retusa) species were recovered from two infected rattlesnakes. One female gopher snake was infected with two nematode (K. inermis and Rhabdias spp.) and one mite (Entonyssus halli) species.     

Optical properties of polypeptides in the β-conformation

The rotational strengths and oscillator strengths of the nπ* band and ππ* exciton bands have been calculated for antiparallel and parallel β-structures of varying length and width. The results are compared with experiment and with previous theoretical treatments of β-structures. The generally good agreement of calculations on the antiparallel β-structure with experimental results on poly-L -lysine and poly-L -serine indicates that these systems are indeed in the antiparallel conformation. It is found that the exciton component strongest in absorption shifts to longer wavelengths as the width of an antiparallel structure increases, and it is suggested that the position of the ππ* absorption band may be a useful criterion of sheet width. The results also reconcile the linear dichroism measurements of Rosenheck and Sommer on poly-L -lysine films with an anti-parallel structure. Calculations on parallel β-structures indicate that the CD spectra of this form will be rather similar to that of the antiparallel form. However, the major absorption band in the antiparallel form is associated with a small positive CD band, while in the parallel form it coincides with a large negative CD band. Finally, it is pointed out that the large positive CD bands predicted for single-stranded parallel and antiparallel β-structures at about 200 mμ render unlikely the suggestion that random-coil polypeptides contain a substantial fraction of extended chain.     

Effects of unilateral castration on morphologic characteristics of the testis in one-, two-, and three-year-old stallions

The effects of unilateral castration on testicular compensatory hypertrophy were measured in 12 Morgan stallions, four each at one, two, and three years of age. They were randomized within age to intact (IN) or unilaterally castrated (UC) groups. Allotment and surgery were in January 1983 and total castration was in June 1983, 150 d after unilateral castration. Testis weight increased linearly with age (P < 0.01) and was increased by unilateral castration (P < 0.07). Epididymal weight also increased linearly with age (P < 0.05) and was heavier in UC animals (P = 0.15). Tubule diameter (P < 0.10) and epithelial height (P < 0.03) were greater in UC than in IN stallions. In conclusion, testes of stallions underwent compensatory hypertrophy after unilateral castration.     

Absolute requirement for adherent cells in the production of human interleukin 2 (IL2)

Activated T lymphocytes appear to require a growth factor, interleukin 2 (IL2), for continued proliferation. It has been hypothesized that T lymphocytes serving an amplifier function produce IL2 in response to an activating signal such as antigen or mitogen; in addition, the producer lymphocytes receive a second signal from macrophages. The present experiments demonstrated that human IL2 production in culture is totally depleted by exhaustive removal of adherent cells and can be completely restored by replacement of the adherent cells.     

The antagonism of bombesin in the CNS by substance P analogues

The ability of substance P analogues to inhibit the action of bombesin in the CNS was investigated using receptor binding and biological assays. The putative substance P antagonists inhibited binding to central receptors for both substance P and bombesin-like peptides. Spantide, which was the most potent analogue tested, reversed the bombesin induced hypothermia and grooming. Therefore the putative substance P antagonists may also antagonize the actions of bombesin in the CNS