Oral exudate as a mediator of behavior in larval eastern and western spruce budworms (Lepidoptera: Tortricidae)

The production of oral exudate by larval eastern and western spruce budworms,Choristoneura fumiferana (Clem.) andChoristoneura occidentalis Free., respectively, was investigated in the laboratory. All larvae except those entering into a molt exhibited aggressive behavior and produced exudate in response to handling or intraspecific encounters. Larvae could be induced to produce exudate up to four times over 2–3 min and produced an average of 1.92±0.04 µl (X ± SE) per induction. Larvae on foliage spent much of their time maintaining their silken feeding tunnel, including spinning and combing silk and removing frass. Exposure to conspecific oral exudate deposited inside the tunnel, or released by agitated larvae inside the tunnel, increased the proportion of larvae that dispersed away from the tunnels and, apparently, increased the larval sensitivity to disturbances. The behavior induced by the oral exudate indicates that it acts as an epideictic (spacing) pheromone.     

Migration of Gasterophilus intestinalis larvae (Diptera: Gasterophilidae) in the equine oral cavity

Cogley T. P., Anderson J. R. and Cooley L. J. 1982. Migration of Gasterophilus intestinalis larvae (Diptera: Gasterophilidae) in the equine oral cavity. International Journal for Parasitology12: 473–480. Larvae of G. intestinalis pursued a specific migratory pathway within the equine oral cavity en route to the stomach. The larval migration included the following sequence: burrowing in the tongue mucosa, invasion of the interdental spaces, transitory attachment at the root of the tongue and movement to the stomach. The molt from first to second instar did not occur in the tongue, as commonly believed, but between the interdental spaces. Ninety five percent of the larvae invading the interdental spaces were associated with gingiva of the upper molars. SEM analysis revealed further details of the oral migration: (1) air holes excavated in the epithelium which connect with deeper burrows; (2) an intimate association between air holes and posterior spiracles of larvae; (3) precise impressions of larvae in tissue immediately surrounding the most recently formed burrows; and (4) initial larval entry into the tongue through the use of natural disruptions or healing lesions. Factors influencing the development of the oral migration are discussed.     

Timing and Regulation of Nuclear and Cortical Events in the Cell Cycle of Tetrahymena pyriformis*

SYNOPSIS. Using continuous flow cultures based on the chemostat principle, we varied the cell generation times of the ciliate Tetrahymena pyriformis strain GL, from 4.9 to 22.2 hr and studied various parameters of the cell cycle at 28 C. These included: the duration of the periods required for oral morphogenesis, macronuclear division, cell division, G₁ S, and G₂. The size of individual cells was also measured. Independent of the growth rate, the period of oral morphogenesis occurred during the last 90 min of the cell cycle. In all cases macronuclear and cell divisions took place during the last part of these 90 min, and the final macronuclear separation occurred just before final cell separation. The S-period increased slightly, while the G₁ and G₂ both increased in roughly the same relative proportion to the increasing generation times. Slowly growing cells (generation time 20.5 hr) were shorter but broader and somewhat larger in volume than quickly growing cells (generation time 4.9 hr).     

A review of the bioavailability of petroleum constituents

Exposure to petroleum constituents at contaminated sites may occur through a variety of pathways, including inhalation of vapors and particulates, ingestion of water and soils, and dermal contact with water and soils. Accurately assessing the human health risks from such exposures requires information on the medium‐ and route‐specific bioavailability of petroleum constituents (e.g., how well these chemicals enter the body via the gastrointestinal tract and skin). For example, when the medium or exposure route in an animal toxicity assay (e.g., ingestion of water) differs from the actual route of human exposure at the petroleum contaminated site (e.g., dermal contact with soil), adjustments should be made that reflect the relative bioavailability of the chemical in the different media. The focus of this article is on (1) the availability of oral and dermal absorption data for one PAH (benzo[a]pyrene, (B[a]P) and three VOCs in soil (benzene, toluene, and xylene); (2) factors affecting the uptake of these PAHs and VOCs from soil; and (3) ways to incorporate bioavailability data into human health risk assessments. Based on our review, we recommend the following default values for the oral and dermal absorption of B[a]P, benzene, toluene, and xylene from soil:

A review of the bioavailability of petroleum constituents

All authors

Jennifer Bramard & Barbara D. Beck

https://doi.org/10.1080/15320389209383417

Published online:

02 December 2008

Display Table

Site‐specific information such as chemical concentrations in soil, soil characteristics, soil loadings on the skin, contact site, and contact time could result in modifications of these numbers. As shown, our default absorption values are generally less than those recommended by the U.S. EPA (1991a,b,c). The implications of these estimates of bioavailability for risk assessment and for the selection of soil cleanup levels at petroleum‐contaminated sites are discussed.     

The use of oral prostaglandin E2 in the management of intrauterine fetal death

12 otherwise healthy patients with intrauterine fetal death 1 to 6 weeks earlier were treated with oral prostaglandin E₂. 9 of the 12 patients delivered within 48 hours after treatment began. 2 others delivered within 48 hours after unsuccessful treatment ceased. In a third patient the cervix relaxed after treatment, and the uterine contents were removed by curettage. No serious complications, such as hemorrhage occurred. The uterus seemed surprisingly responsive to oral prostaglandin E₂ in cases of intrauterine fetal death.     

叶下珠有效部位对血栓形成的影响及其作用机制初探

采用Born方法和改良的Hamburger方法分别测定叶下珠 (Phyllanthusurinaria)含corilagin的有效部位 (代号PUW )在体内外对血小板聚集功能和对血小板与中性粒细胞之间粘附反应的影响 ;应用Myers方法评价PUW灌胃对小鼠尾静脉注射花生四烯酸 (AA)引起猝死的保护作用 ;运用改良的Charl ton方法及陈长勋等方法分别观察PUW灌胃对电刺激大鼠颈动脉血栓形成和下腔静脉血栓形成的影响 ;采用Tomihisa方法 ,观察PUW对大鼠尾尖出血时间的影响。结果显示 ,PUW在体内外对ADP、AA或血小板活化因子 (PAF)诱导的血小板聚集均无明显抑制作用 ;PUW呈浓度依赖性明显阻抑AA激活的血小板与中性粒细胞之间的粘附反应 ,其半数抑制浓度 (IC50 )为 39 7mg/kg。PUW (10、2 0和 4 0mg/kg)灌胃呈剂量依赖性显著减少AA致小鼠死亡的数量 ,明显延长电刺激大鼠颈动脉血栓形成时间 ,减轻大鼠下腔静脉血栓的干、湿重。 2 0mg/kg的PUW对出血时间无明显影响 ,4 0mg/kg的PUW虽延长出血时间 ,但与阿司匹林 (2 0mg/kg)比较 ,出血时间明显缩短 (P <0 0 5 )。本实验结果提示 ,PUW灌胃在多种体内血栓模型中均具有明显的抗血栓形成作用 ,其机制可能与阻抑血小板和中性粒细胞之间的的粘附作用密切相关。     

Plant‐based oral vaccines against zoonotic and non‐zoonotic diseases

The shared diseases between animals and humans are known as zoonotic diseases and spread infectious diseases among humans. Zoonotic diseases are not only a major burden to livestock industry but also threaten humans accounting for >60% cases of human illness. About 75% of emerging infectious diseases in humans have been reported to originate from zoonotic pathogens. Because antibiotics are frequently used to protect livestock from bacterial diseases, the development of antibiotic‐resistant strains of epidemic and zoonotic pathogens is now a major concern. Live attenuated and killed vaccines are the only option to control these infectious diseases and this approach has been used since 1890. However, major problems with this approach include high cost and injectable vaccines is impractical for >20 billion poultry animals or fish in aquaculture. Plants offer an attractive and affordable platform for vaccines against animal diseases because of their low cost, and they are free of attenuated pathogens and cold chain requirement. Therefore, several plant‐based vaccines against human and animals diseases have been developed recently that undergo clinical and regulatory approval. Plant‐based vaccines serve as ideal booster vaccines that could eliminate multiple boosters of attenuated bacteria or viruses, but requirement of injectable priming with adjuvant is a current limitation. So, new approaches like oral vaccines are needed to overcome this challenge. In this review, we discuss the progress made in plant‐based vaccines against zoonotic or other animal diseases and future challenges in advancing this field.     

Biomanufacturing of protective antibodies and other therapeutics in edible plant tissues for oral applications

Although plant expression systems used for production of therapeutic proteins have the advantage of being scalable at a low price, the downstream processing necessary to obtain pure therapeutic molecules is as expensive as for the traditional Chinese hamster ovary (CHO) platforms. However, when edible plant tissues (EPTs) are used, there is no need for exhaustive purification, because they can be delivered orally as partially purified formulations that are safe for consumption. This economic benefit is especially interesting when high doses of recombinant proteins are required throughout the treatment/prophylaxis period, as is the case for antibodies used for oral passive immunization (OPI). The secretory IgA (SIgA) antibodies, which are highly abundant in the digestive tract and mucosal secretions, and thus the first choice for OPI, have only been successfully produced in plant expression systems. Here, we cover most of the up‐to‐date examples of EPT‐produced pharmaceuticals, including two examples of SIgA aimed at oral delivery. We describe the benefits and drawbacks of delivering partially purified formulations and discuss a number of practical considerations and criteria to take into account when using plant expression systems, such as subcellular targeting, protein degradation, glycosylation patterns and downstream strategies, all crucial for improved yield, high quality and low cost of the final product.