Characterization of a Bacillus thuringiensis delta-endotoxin which is toxic to insects in three orders.

We report here the first Bacillus thuringiensis (Bt) toxin which is toxic to insects from three insect orders (Diptera, Coleoptera, and Lepidoptera). An oligonucleotide probe based on the delta-endotoxin N-terminal sequence was used to detect the gene. A 23-kb BamHI fragment containing the intact gene was identified and cloned from Bt strain YBT-226 plasmid DNA into the vector pBluescript II. Through a series of DNA manipulations the size of this fragment was reduced and the gene sequenced. The deduced amino acid sequence gave a predicted molecular mass of 137 kDa and was identical to a cry1Ba protein from Bt subsp. thuringiensis HD-2, which is now designated as Cry1Ba1 under a new classification scheme. This protein also showed 81.6% similarity with the Cry1B protein (Cry1Bb1) from Bt strain EG 5847. When the YBT-226 cry1Ba1 gene was expressed in an acrystalliferous Bt subsp. israelensis strain it produced irregular bipyramidal crystals during sporulation, which reacted specifically with anti-Cry1Ba antiserum. Bioassays using these crystals after purification resulted in significant mortality at low to moderate concentrations to larvae of the house fly (Musca domestica, Diptera), cottonwood leaf beetle (Chrysomela scripta, Coleoptera), and tobacco hornworm (Manduca sexta, Lepidoptera). This broad-spectrum toxicity was not dependent on presolubilization. In assays with insect cell lines not derived from midgut cells, the soluble toxin killed CH1t (Manduca sexta cells) but was inactive against CF1 (Choristoneura fumiferana cells), Aa(s) (Aedes aegypti), and C2 (Culex quinquefasciatus) mosquito cells.

Laboratory and field evaluations of two Bacillus thuringiensis formulations, Novodor and Raven, for control of cottonwood leaf beetle (Coleoptera: Chrysomelidae).

Laboratory and field experiments were conducted to determine the efficacy of two Bacillus thuringiensis Berliner formulations, Novodor and Raven, for controlling cottonwood leaf beetle, Chrysomela scripta F. (Coleoptera: Chrysomelidae). In laboratory bioassays, larvae or adults were added to petri dishes containing Populus x euramericana Guinier 'Eugenei' foliage that had been treated with distilled water (control) or one of the commercial Bt formulations at either high or low label rates. Survival was recorded on a 24-h basis, and leaf area consumed was measured at the conclusion of all trials. Significant differences from the control in mortality and leaf area consumption resulted in the Novodor and Raven treatments for all life stages tested; however, adults were better able to withstand the effects of B. thuringiensis toxins than were the immatures. Early- and late instar C. scripta populations were monitored in the field (1998 and 1999) after treatment with either water or various concentrations of one of the commercial Bt formulations. Significant mortality resulted with all concentrations and for all life stages tested compared with the control (tap water). The commercial formulations also were tested under plantation conditions as part of a long-term defoliation study. Both Novodor and Raven reduced cottonwood leaf beetle defoliation damage after a single application, giving high efficacy for control of cottonwood leaf beetle under the conditions and concentrations evaluated.

Uptake of [(3)H]glycine by synaptosomes of channel.

It is known that channel catfish erythrocytes can take up glycine by several distinct transport systems. Further, glycine is an inhibitory neurotransmitter in mammalian brain and spinal cord. Consequently, the uptake of [(3)H]glycine by catfish brain was investigated and found to be a saturable process, dependent on the presence of Na(++) and Cl(--) and sensitive to temperature. A kinetic analysis of transport was performed at 22C. This showed that a high-affinity system existed which exhibited a K(m) of 5.1 (+/- 2. 1) microM. Several structural analogues of glycine were capable of inhibiting uptake in a competitive manner. The most effective inhibitor was sarcosine (IC(50) 5 36 microM). Uptake was also able to be inhibited by harmaline, a drug known to interfere with Na(+)-dependent transport processes. It is concluded that glycine transport by channel catfish brain has much in common with transport by mammalian nervous tissue which is carried out by the membrane carriers GLYT1 and GLYT2. On the other hand, synaptosomal transport differs somewhat from glycine transport by channel catfish erythrocytes.

Ocular effects of oral contraceptives. II. Studies in the rhesus monkey.

Oral contraceptives were administered cyclically to 96 female rhesus monkeys for 5 years. Forty-eight animals received Enovid-E and 48 were treated with Ovulen at doses 1, 10, and 50 times the human dose. Ophthalmic lesions did not occur at any of the dose levels employed. Significant fundic lesions, including papilledema, venous dilatation, venous retinal thrombosis, or arterial retinal thrombosis, did not develop in any of the treated animals.

Effect of oral contraceptives on the mammary glands of Rhesus monkeys: a preliminary report.

PIP: To determine the relationship of oral contraceptive use and breast cancer, 96 rhesus monkeys were administered either Enovid-E (2.5 mg norethynodrel and .1 mg mestranol) or Ovulen (1 mg ethynodiol diacetate and .1 mg mestranol) cyclically for 5 years at doses of 1, 10 and 50 times the human dose. The animals' progress was compared with a control group of 32 monkeys. General physical and mammary gland examinations were conducted before treatment and monthly thereafter. During the 5 year study period none of the treated animals demonstrated clinical evidence of mammary gland lesions, no deaths from breast malignancy occurred, and no palpable breast nodules were found.^ieng