Relative estimation of ventilatory fow rate in the eel (Anguilla anguilla L.)

Freshwater eels (Anguilla anguilla L.) were experimented on in order to measure ventilatory flow rate (by means of a direct method of collecting expired water), and simultaneously, to record sub-opercular pressure changes and opercular displacements (operculogram). Significant correlations (p less than 0.01) were found between the ventilatory flow rate (V) and various characteristics of operculiogram records. The relationships which are significant in each fish experimented on are; V = a(f.lo) + b; V = a(f.Ao) % b and V = a(f.Ao2) + b(f: ventilatory frequency: Ao and lo: mean amplitude and result of integration of opercular tracings). Considering the technical difficulties in measuring the ventilation flow rate of the eel, the easier operculographic recording methods lead to a correct estimation of relative changes in ventilatory flow rate, by using the refined relationship: V = a(Ao1.63).     

Switch in rod opsin gene expression in the European eel, Anguilla anguilla (L.)

The rod photoreceptors of the European eel, Anguilla anguilla (L.), alter their wavelength of maximum sensitivity (lambda max) from c.a. 523 nm to c.a. 482 nm at maturation, a switch involving the synthesis of a new visual pigment protein (opsin) that is inserted into the outer segments of existing rods. We artificially induced the switch in rod opsin production by the administration of hormones, and monitored the switch at the level of mRNA accumulation using radiolabelled oligonuleotides that hybridized differently to the two forms of eel rod opsin. The production of the deep-sea form of rod opsin was detected 6 h after the first hormone injection, and the switch in rod opsin expression was complete within four weeks, at which time only the mRNA for the deep-sea opsin was detectable in the retinal cells. It is suggested that this system could be used as a tractable model for studying the regulatory control of opsin gene expression.     

A method to measure the rate of metabolic clearance and secretion of cortisol in the eel (Anguilla anguilla L.)

Classical methods for the analysis of steroid dynamics were adapted to measure the metabolic clearance rate and the secretion rate of cortisol in the European eel using (1, 2-3H) cortisol as a tracer. 1. Measurements were made whilst the eels were in the steady state; stresses which usually result from anaesthesia and handling were avoided by chronic catheterization of the blood vessels of the swim bladder. In this way, the plasma cortisol level were constant; thus, it was possible to obtain valid measurements of the cortisol secretion rate knowing the metabolic clearance rate and the plasma cortisol level. 2. In the eel, cortisol and cortisone together form a chemical compartment', derived originally from cortisol secreted by the interrenal gland and subsequently transformed partially into cortisone in the plasma and maintained thenceforth in dynamic reversible equilibrium. Consequently, the metabolic clearance rate of cortisol has been calculated from the known changes in concentration of both (1, 2-3H) cortisol and (1, 2-3H)cortisone in the plasma deduced from dichloromethane-extractable plasma radioactivity, 72% of which is always attributable to these two steroids from the moment that the radioactivity begins to decline regularly as a function of time (15-30 min after the injection). 3. After a single injection of (1,2-3H) cortisol, the interpretation of the disappearance curve by compartmental analysis is complicated by the delay of tracer distribution and by the evident variability in the initial portion of the curve. Disappearance curves have accordingly been analysed in a more rigorous fashion either by integrating the area under each curve which allows one to calculate individually the metabolic clearance rates, or by integrating according to Normand, M., and Fortier, C. (1970. Can. J. Physiol. Pharmacol. 48, 274-281) which allows one statistical treatment of data. 4. Estimates of the metabolic clearance rate of cortisol were made in a satisfactory manner by either one of the two integration methods. They were also very similar to estimates obtained by prolonged infusion of (1, 2-3H) cortisol to constant specific activity into eels maintained under identical experimental conditions.     

Bioconcentration and excretion of fenitrothion in the brain of the eel (Anguilla anguilla)

The bioconcentration of fenitrothion in the brain of the european eel (Anguilla anguilla) and its posterior elimination have been studied. Animals were exposed to a sublethal concentration of fenitrothion (0.04 mg/L) for 96 hours in a flow-through test system. After this pesticide exposure, animals were transferred to clean water for 72 hours more. Bioconcentration and elimination processes of fenitrothion were studied in blood and brain. This insecticide showed a strong tendency to bioconcentrate into selected tissues. A steady-state was observed in blood in few hours. Highest accumulation was detected in brain, where any steady-state could be observed. Elimination started rapidly from both tissues when a recovery period was allowed. Elimination kinetics were adjusted to one-compartment model. K2 of 0.015 and 0.044 hr-1 were calculated for fenitrothion in blood and brain. These K2 values were related with a relatively short half-live of fenitrothion in the analyzed tissues; probably due to the low biotransformation rate of this toxicant in the european eel. That fact would protect the animals against many biotransformation products even more toxic than the parent fenitrothion.     

Morphological, cytological, and biochemical changes of Anguilla anguilla L. gills deprived of Stannius corpuscles (S. C.) (author's transl)

In the silver female eel (Anguilla anguilla L.) maintained in fresh water, surgical removal of Stannius corpuscles (SC) resulted in: a) A significant increase of wet weight of gill cells and the dry weight of gill filaments expressed as function of body weight. b) A proliferation and a hypertrophy of chloride cells shown by a significant rise of cell volume expressed as a precentage of the epithelial volume. c) An increase of the calcium (Ca) binding protein activity in the total branchial mucosa. These modifications are not observed when eels are maintained in Ca-free water. The results are discussed in relation to the Ca fluxes across gills in eels deprived of SC and gill morphological changes during sea water adaptation.     

Metal-induced genotoxic adaptation in barley (Hordeum vulgare L.) to maleic hydrazide and methyl mercuric chloride

Presoaked seeds of barley, Hordeum vulgare L., were exposed for 2 h to maleic hydrazide (MH), 5 x 10(-2) M or methyl mercuric chloride (MMCl), 10(-4) M with or without a prior conditioning with MH, 5 x 10(-3) M; MMCl, 10(-5) M; cadmium sulfate (CdSO4), 10(-4) M or zinc sulfate (ZnSO4), 10(-1) M; the interexposure time was 2 h. Subsequently as the seeds germinated a number of endpoints were measured that included mitotic index, mitotic chromosome aberrations and micronuclei (MNC) in embryonic shoot cells fixed at 32, 36, 40, 44, 48 and 52 h of recovery, and seedling height on day 7. The results demonstrated that prior conditioning exposure to MH or metals induced genotoxic adaptation to the subsequent challenge exposure to MH and MMCl. Cadmium-induced genotoxic adaptation against either MH or MMCl challenge exposure was, however, significantly prevented when the presoaked seeds were pre-exposed to buthionine sulfoximine, 10(-3) M for 2 h, thereby providing evidence that the underlying mechanism of genotoxic adaptation possibly involved phytochelatins.     

The effect of serotonin and transcapillary pressure on the capillary permeability in the rete mirabile of the eel (Anguilla vulgaris l.)

A frame of reference for studying human disease is presented. An individual's social behavior serves as the orienting theme. Special forms of social behavior are in effect what tie an individual to his physical and social space, and alterations here can lead to disease. Causes of disease can thus be linked to behaviors of the individual. Although associated with basic changes in the psysiologies and chemistries of the individual, disease invariably comes to affect the individual's behavior and adaptation. Different ways in which such behavioral changes can be conceptualized are discussed. The individual relies on these behavioral changes as the data for evaluating his disease and deciding about medical treatment. A model of how an individual processes information about illness and makes decisions designed to alleviate his condition is presented. Finally, the rationale and value of keeping behavior and adaptation in mind when studying disease are discussed.     

豹斑毒鹅膏菌毒素粗品对黄粉虫的毒性研究

[目的]探讨豹斑毒鹅膏菌毒素粗品对黄粉虫的毒性.[方法]测定了5种大型真菌子实体及毒素粗品对黄粉虫的毒杀活性,并对筛选出的豹斑毒鹅膏菌进行了致死效应研究.[结果]随着豹斑毒鹅膏菌毒素粗品浓度的增大,防治效果越来越明显.当豹斑毒鹅膏菌毒素粗品浓度为17.5 mg/ml时,黄粉虫死亡率为93.3%,效果显著.[结论]豹斑毒鹅膏菌毒素粗品对黄粉虫有较显著的毒杀作用.     

Acute and subacute toxicity of atrazine to carp (Cyprinus carpio L.)

Investigations of acute and subacute atrazine toxicity in carp (Cyprinus carpio L.) were carried out. Acute toxicity was investigated in a semi-static test during a 96-hr exposition. The estimated LC-50 value was 18.8 mg/l. Subacute toxicity was investigated by exposing fish (carp) to different atrazine concentrations (1.5, 3.0, and 6.0 mg/l) for 14 days. Biochemical and histopathological changes in certain organs and tissues were investigated. The results show that atrazine leads to changes of varying intensity depending on the parameter tested, the organs and tissues examined, as well as the atrazine concentration. Biochemical changes were most prominent in the alkaline phosphatase, glutamic-oxaloacetic transaminase, and glutamic-pyruvic transaminase activities whereas the most severe histopathological changes were observed in the gills.     

Implicit and self-attributed dependency strivings: differential relationships to laboratory and field measures of help seeking

Inflammatory processes occurring in the vicinity of bone tissue often result in stimulation of osteoclast activity and loss of skeletal mass. The aim of the current study was to determine if inflammatory exudates collected from gingival pockets in patients with periodontitis contain factors capable of stimulating resorptive activity. The degree of bone mineral mobilization and bone matrix degradation was assessed by analysis of the release of 45Ca and 3H from bones prelabelled with 45CaCl2 and [3H]proline, respectively. Gingival crevicular washings from six patients with signs of periodontitis stimulated 45Ca or 3H release from the calvarial bones. The stimulatory effect of the gingival crevicular washings on 45Ca release was concentration- and time-dependent, and reduced by calcitonin, a specific osteoclast inhibitor. These data demonstrate that crevicular fluid contains factor(s) which can stimulate osteoclastic degradation of bone in vitro. The bone resorbing activity was partially retained after extensive dialysis. Analysis of the concentrations of prostaglandin E2, interleukin-1alpha and interleukin-1beta in the crevicular fluids, and comparisons of these agents as stimulators of 45Ca release in the mouse calvarial assay, suggest that prostaglandin E2 is not the sole factor responsible for the bone resorbing activity of the exudates. The data indicate that other factors, such as IL-1, may play key roles in the stimulation of osteoclastic activity by gingival crevicular washings.     

Children's responses to adult–adult and mother–child arguments: The role of parental marital conflict and distress.

Children's responses to verbal and physical conflict between adult–adult, mother–girl, and mother–boy participants were examined as a function of parental marital conflict. Seven- to 9-year-olds viewed videotaped arguments and were then interviewed. In comparison with children from low-conflict homes, children from high-conflict homes perceived the actors engaged in both the interadult and mother–child disputes as more angry and reported feeling more fearful during these arguments. The results extend support for the sensitization hypothesis and indicate that parental marital conflict exacerbates children's perceptions of conflict and fear responding to not only interadult disputes but also to mother–girl and mother–boy conflict. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Laboratory and field evaluations of oviposition responses of Aedes albopictus and Aedes triseriatus (Diptera: Culicidae) to oak leaf infusions

Organic infusions created by fermenting white oak (Quercus alba L.) leaves in water were evaluated as sources of attractant odorants and contact oviposition stimulants for gravid Aedes albopictus (Skuse) and Aedes triseriatus (Say). Infusions were bioassayed in the laboratory by giving single females a choice of ovipositing in 1 container with infusion and 7 containers with water. Ae. albopictus laid significantly more eggs in containers with infusion, regardless of concentration (dilutions ranging from 10 to 100%) or age (fermentation periods of 7, 28, 60 d), than in containers holding water. The largest proportion of eggs (76.8%) was deposited in response to a 60% concentration of 7-d-old infusion. In contrast, Ae. triseriatus exhibited variable oviposition responses but generally deposited the largest number of eggs in only a few concentrations of older age infusions. In binary "sticky screen" bioassays, there was no difference between the numbers of females attracted to infusion or water, indicating that oviposition responses to infusion were mediated by contact chemostimulants rather than by attraction to odorants. Oviposition responses to infusions by field populations of Ae. albopictus and Ae. triseriatus in Raleigh, NC, were evaluated with pairs of oviposition traps, one containing infusion and the other containing water. Generally, Ae. albopictus laid significantly more eggs in ovitraps containing infusion regardless of its age (7, 28, and 60 d old) or the mass of leaves fermented (126 g = 1x or 504 g = 4x) than in water. In contrast, Ae. triseriatus deposited an equivalent number of eggs in traps containing water or 1x, 80% infusion regardless of its age; however, the oviposition response to ovitraps containing 4x, 7-d-old, 50% infusion was significant. Placement of an automobile tire behind an ovitrap did not increase the number of Ae. albopictus eggs laid in ovitraps containing 4x, 7-d-old, 50% infusion or water relative to ovitraps without a tire. Our research indicates that baiting ovitraps with oak leaf infusion would increase the sensitivity of surveillance efforts for Ae. albopictus and Ae. triseriatus.     

Reactions of the goldfish (Carassius auratus auratus L.) to quantified mechanical and thermal stimuli

Goldfish can differentiate between mechanical and thermal stimuli components in combined stimulations. Reactions to heated thermode (deltaT = + 3 degrees C) differ from those to isotherm thermode by up to 30%. Additional pretension (0.5 p) increases the reaction more than double; at simultaneously varied temperature (deltaT = + 3 degrees C and + 5 degrees C), there is a further increase in reaction of 25% and 35%. The significance for the organism of the two stimuli components is discussed.     

Determination of the digestibility of crude nutrients and amino acids of 2 horse bean (Vicia faba L.) varieties in colostomized laying hens

The apparent digestibility of crude nutrients and the amino acids in the varieties Fribo and Erfordia of horse bean (Vicia faba L.) was determined in a digestibility and N-balance experiment with 32 colostomised laying hen hybrids. For this purpose 4 rations each with a rising quota of horse beans (10%, 20%, 40%, 50%) were tested with 4 hens each in a 6-day collecting period; the digestibility values were determined according to the regressive method. The average apparent digestibility is (formula; see text) The values of the apparent digestibility of the 17 amino acids vary for the variety Fribo between 68.6% (methionine) and 90.6% (arginine) and for the variety Erfordia between 47.7% (cystine) and 89.5% (arginine).     

Neonatal and early life immune responses to various forms of vaccine antigens qualitatively differ from adult responses: predominance of a Th2-biased pattern which persists after adult boosting

Induction of neonatal immune responses to vaccine antigens is believed to be of limited efficacy because of immune immaturity and particular susceptibility to tolerogenic signals during this period of life. To characterize particular features of neonatal immune responses to vaccine antigens, we assessed the capacity of BALB/c mice at different stages of immunological maturation to respond to a selection of vaccine antigens and presentation systems. Significant B and T cell responses to vaccine antigens (tetanus and measles virus peptides, tetanus toxoid, live viral attenuated measles virus, canarypox recombinant measles vector or bacillus Calmette-Guérin) were obtained as early as the first week of life. However, these neonatal responses differed qualitatively from adult responses by a decreased IgG2a/IgG1 ratio of vaccine-specific antibodies, the secretion of significantly higher interleukin-5 and lower interferon-gamma levels by vaccine-specific T cells and an impaired induction of cytotoxic T cell precursors. This pattern of biased Th2 versus Th1 responses induced upon early exposure to vaccines was not reversed by decreasing the doses of vaccine antigens. It did not disappear with aging and was still reflected in adult responses to booster immunization with the corresponding antigen. Thus, neonatal immunization can induce significant vaccine specific responses with a predominance of a Th2 pattern which can persist in boosted adult mice.     

Behavioral and glucocorticoid responses of adult domestic dogs (Canis familiaris) to companionship and social separation.

Removal of 1 member of a long-standing pair of adult domestic dog (Canis familiaris) kennel mates from the home run for 4 hr had no effect on the behavior or plasma glucocorticoid levels of the remaining dog. When tested in a novel environment, dogs showed increased activity and elevated glucocorticoid levels at the end of the session, but these responses were as large when the dogs were with their kennel mates as when they were alone. However activity and glucocorticoid levels were not elevated if the dogs were exposed to the novel environment in the presence of their human caretaker. Dogs more often were observed in proximity with, and soliciting social behavior from, the human than the kennel mate. These results highlight the importance of human companionship for the domestic dog and point to a difference in the nature of the social relationships of dogs with humans and with conspecifics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Blood cells of the gilthead seabream (Sparus aurata L.): light and electron microscopic studies

The peripheral blood cells of the gilthead seabream (Sparus aurata L.) were studied by light and transmission and scanning electron microscopic methods. Acidophilic erythroblasts and mature erythrocytes, round, oval, and fusiform thrombocytes, neutrophils, acidophils and basophils, lymphocytes, plasma cells, and monocyte-macrophages were characterized. A comparison of our light and electron microscopic results was carried out. The results were discussed with those for other fish species and the main modifications from the common vertebrate haematological pattern observed being considered.     

Xanthophyll biosynthesis: molecular and functional characterization of carotenoid hydroxylases from pepper fruits (Capsicum annuum L.)

In analysis, comparison and classification of conformations of proteins, a common computational task involves extractions of similar substructures. Structural comparisons are usually based on either of two measures of similarity: the root-mean-square (r.m.s.) deviation upon optimal superposition, or the maximal element of the difference distance matrix. The analysis presented here clarifies the relationships between different measures of structural similarity, and can provide a basis for developing algorithms and software to extract all maximal common well-fitting substructures from proteins. Given atomic coordinates of two proteins, many methods have been described for extracting some substantial (if not provably maximal) common substructure with low r.m.s. deviation. This is a relatively easy task compared with the problem addressed here, i.e., that of finding all common substructures with r.m.s. deviation less than a prespecified threshold. The combinatorial problems associated with similar subset extraction are more tractable if expressed in terms of the maximal element of the difference distance matrix than in terms of the r.m.s. deviation. However, it has been difficult to correlate these alternative measures of structural similarity. The purpose of this article is to make this connection. We first introduce a third measure of structural similarity: the maximum distance between corresponding pairs of points after superposition to minimize this value. This corresponds to fitting in the Chebyshev norm. Properties of Chebyshev superposition are derived. We describe relationships between the r.m.s. and minimax (Chebyshev) deviations upon optimal superposition, and between the Chebyshev deviation and the maximal element of the difference distance matrix. Combining these produces a relationship between the r.m.s. deviation upon optimal superposition and the maximal element of the difference distance matrix. Based on these results, we can apply algorithms and software for finding subsets of the difference distance matrix for which all elements are less than a specified bound, either to select only subsets for which the r.m.s.deviation is less than or equal to a specified threshold, or to select subsets that include all subsets for which the r.m.s. deviation is less than or equal to a threshold.