Consort Intrusion and Female Mate Choice in Japanese Macaques (Macaca fuscata)

Consort intrusion behavior has been proposed to largely function as a means of preventing or suppressing the reproductive activity of subordinate males. In the Japanese macaques of Arashiyama B troop this behavior was found to be ineffective in influencing female mate choice and affecting differential reproduction. Mainly directed towards the female of the pair intrusion resembled sexual solicitation and appeared to be an extension of consort behavior. Although the intruder male was almost always dominant over the other male, intrusion failed to provide priority of access to the estrous female as she most frequently chose to remain with her current partner. Copulations which were intruded upon were as likely to end in ejaculation as those which were undisturbed. Only a small proportion of intruder male-female pairs mated. Pairs that did mate were likely to have been in consort before or during the period in which intrusion occurred. No significant correlation was found between male rank order and number of possible females impregnated. Individual young, middle to lower ranking males were estimated to have been reproductively the most successful.     

A toxin fromPasteurella multocida serogroup D enhances swine herpesvirus 1 replication/lethality in vitro and in vivo

In swine, the nasal turbinate epithelium is both a site of swine herpesvirus 1 (pseudorabies virus, PRV) replication and a tissue affected by toxin fromPasteurella multocida serogroup D. We examined the effects of exposure to PRV and exposure to toxin in mice, swine, and nasal turbinate cell cultures. Increased mortality in mice was observed when nonlethal doses of PRV (1000 or 100 plaque-forming units, PFU) were administered along with nonlethal doses (60–200 ng/kg) of toxin. In swine, clinical disease and death in adult pigs was observed after an intradermal injection of toxin (20 ng/kg) and intranasal exposure to 1000 PFU/kg of PRV. Nasal turbinate cell cultures incubated with toxin and PRV had increased protein synthesis, DNA synthesis, and increased recovery of virus particles. These findings indicate that a toxin fromP. multocida serogroup D enhances swine herpesvirus 1 replication and lethality in cell cultures and animal models.     

Comparison of chemical analyses of boat and helicopter-collected water samples

Helicopters can be used to collect water samples from many lakes over a wide geographic area within a relatively short time period. Here we report the results from an experiment in which sequential water samples from a lake were collected first from a nonmotorized boat and then immediately afterward from a helicopter. No significant differences were found between the means of the measurement of 20 chemical parameters for the two methods of collection. When compared to obtaining samples from a boat, collection of samples from a helicopter platform had no effect on the content of the water samples.     

A new facultatively nitrite oxidizing bacterium,Nitrobacter vulgaris sp. nov.

A total of 17 facultatively lithoautotrophic strains of Nitrobacter were investigated. They all were found to be related on the species level by DNA hybridizations. The G+C content of DNA ranged between 58.9 and 59.9 mol %. The isolates originated from divers environments. The cells were 0.5–0.8×1.2–2.0 m in size and motile by one polar to subpolar flagellum. Cell-division normally occurred by budding. Polar caps of intracytoplasmic membranes as well as carboxysomes were present. The cells tended to excrete extracellular polymers forming aggregates or biofilms. Heterotrophic growth was slower than mixotrophic but often faster than litoautotrophic growth. In the presence of nitrite and organic substances the organisms often showed diphasic growth. First nitrite and then the organic material was oxidized. In the absence of oxygen growth was possible by dissimilatory nitrate reduction. Nitrite, nitric and nitrous oxide as well as ammonia were formed. Depending on growth conditions the generation times varied from 12 to 140 h. The new Nitrobacter spec. may be one of the most abundant nitrite-oxidizing bacteria in soils, fresh waters and natural as well as artificial stones. For this organism the name Nitrobacter vulgaris is proposed.The type strain is filed with the culture collection of the Institut für Allgemeine Botanik, Universität Hamburg, FRG.     

Internal seiches in Lake Constance: influence on plankton abundance at a fixed sampling site

During thermal stratification, pronounced internal seiches occurin Lake Constance with periods of 4–6 days The amplitudesreach 12 m at the sampling site in berlinger See (northwesternpart of Lake Constance). Seiches change the thickness of thewarm and generally biologically rich epilimnion and, thus, alsothe areal abundance of planktonic organisms at a fixed samplingsite. The potential impact of seiche-dnven changes of epilimneticthickness on observed plankton abundance was calculated usingcontinuously recorded temperature profiles and weekly verticalprofiles of plankton biomass. Observed plankton biomass wasrecalculated by taking into account the effect of changing layerthickness in order to give a more realistic picture of biomasschanges caused by waxing and waning of populations Our calculationsimply that changes of strata thickness do not mask the generalseasonal trend in population dynamics (e g. spring bloom andclear water phase), estimates of average yearly standing stockare not significantly affected if sampling is done at leastweekly. However, changes of strata thickness can alter arealplankton abundance at the sampling site by a factor of 2 within2 days During pronounced seiches, areal abundance of phytoplankton,which generally exhibit a stronger vertical gradient than-mostother plankton, may be changed by a factor of 3–4 withinhours Hence, at our sampling site, the impact of changes instrata thickness cannot be ignored for detailed analysis ofpopulation dynamics of autotrophs involving comparisons betweensingle observations     

Stimulation of insulin release from pancreatic islets by quinones

Coenzyme Q (CoQ₀) and other quinones were shown to be potent insulin secretagogues in the isolated pancreatic islet. The order of potency was CoQ₀benzoquinonehydroquinonemenadione. CoQ₆ and CoQ₁₀ (ubiquinone), duroquinone and durohydroquinone did not stimulate insulin release. CoQ₀'s insulinotropism was enhanced in calcium-free medium and CoQ₀ appeared to stimulate only the second phase of insulin release. CoQ₀ inhibited inositol mono-, bis- and trisphosphate formation. Inhibitors of mitochondrial respiration (rotenone, antimycin A, FCCP and cyanide) and the calcium channel blocker verapamil, did not inhibit CoQ₀-induced insulin release. Dicumarol, an inhibitor of quinone reductase, did not inhibit CoQ₀-induced insulin release, but it did inhibit glucose-induced insulin release suggesting that the enzyme and quinones play a role in glucose-induced insulin release. Quinones may stimulate insulin release by mimicking physiologically-occuring quinones, such as CoQ₁₀, by acting on the plasma membrane or in the cytosol. Exogenous quinones may bypass the quinone reductase reaction, as well as many reactions important for exocytosis.     

The Isolation and Evaluation of Two Naturally Occurring Mild Strains of Vanilla Necrosis Potyvirus for Control by Cross-Protection

In an attempt to find mild virus strains that would cross-protect sgainst vanilla necrosis potyvirus (VNPV), Vanilla fragrans plants in Tonga were surveyed for the presence of mild or symptomless potyvirus infections. Potyviruses were detected by indirect ELISA using a commercially available portyvirus group monoclonal anibody. From 28 plants with mild or symptomless infections two portyvirus isolates, designated V1 and V3, included systemic infections in Nicotiana benthamiana following mechanical inoculation. V1, which causes a mild mottle in N. benthamiana, is serologically related to VNPV, while V3 which causes mild vein banding is serologically unrelated to VNPV. Prior inoculation with V1 protected N. benthamiana against the severe mosaic symptoms of VNPV when challenge inoculated after 14 and 21 days, but not after 7 days. When V3 was used as the protecting strain, cross-protection was observed in some, but not all plants, when chalenged with VNPV after 14 and 21 days.     

Whole-embryo culture of Drosophila : development of embryonic tissues in vitro

Summary We have devised techniques to culture whole, dissected embryos of Drosophila melanogaster. We examine multiple aspects of the morphological and physiological development of the epidermis, musculature, nervous system, and internal organs in this cultured preparation, and show that in vitro development closely parallels normal embryogenesis. These techniques permit a wide range of experimental manipulations during embryogenesis and allow us to extend observations through late embryonic stages, after cuticle deposition. Applications of this technique are presented.