Studies on the prolonged storage of Metarhizium anisopliae conidia: effect of temperature and relative humidity on conidial viability and virulence against mosquitoes

The shell lengths, dried shell weights, soft tissue wet weights, and soft tissue dry weights were ascertained for noninfected Ilyanassa obsoleta and for the same snail species naturally infected with the following digeneans: Himasthla quissetensis, Zoogonus lasius, Cercaria dipterocerca, Lepocreadium setiferoides, Microphalloides nassicola, Stephanostomum tenue, and Microbilharzia variglandis. Analyses of the data obtained indicate that infection with all of the trematodes listed above causes neither enhanced growth of soft tissues nor accelerated lengthening of the shell. However, snails infected with sporocysts of Z. lasius have significantly heavier shells than do noninfected snails. These data suggest that infection with Z. lasius may have caused enhanced growth in the form of increased calcium deposition in the shell of I. obsoleta, possibly as a result of parasitic castration. In addition, the mean dry weight of the soft tissues of snails infected with M. variglandis, when normalized for shell length, is significantly lower than that of noninfected snails, possibly as a result of parasite-induced pathology. Finally, comparisons among infected snails indicate a trend toward increased soft tissue dry weight in snails infected with L. setiferoides, although the mean dry weight of these snails does not differ significantly from the mean dry weight of noninfected snails.     

Elevation of aminopeptidase activity in Biomphalaria glabrata (Mollusca) parasitized by Echinostoma lindoense (Trematoda)

Comparisons of the levels of aminopeptidase activity in the hemocytes and serum of Biomphalaria glabrata at 20 and 30 days postexposure to irradiated Echinostoma lindoense miracidia with enzyme levels in control snails have revealed that there are significant elevations in the serum of snails at both time periods postexposure. Furthermore, there is a significantly higher level of aminopeptidase activity in the serum of snails at 30 days than at 20 days postexposure. Although the biologic function of the elevated levels of serum aminopeptidase in sensitized snails remains uncertain, it is possible that this lysosomal enzyme may degrade the surface proteins of secondarily introduced parasites and thus act as a form of acquired humoral immunity.     

Host quality and spatial patterning in infections of the Eastern mudsnail (Ilyanassa obsoleta) by two trematodes (Himasthla quissetensis and Zoogonus rubellus)

Several studies have suggested that the fitness of a parasite can be directly impacted by the quality of its host. In such cases, selective pressures could act to funnel parasites towards the highest-quality hosts in a population. The results of this study demonstrate that snail host quality is strongly correlated with spatial patterning in trematode infections and that habitat type is the underlying driver for both of these variables. Two trematodes (Himasthla quissetensis and Zoogonus rubellus) with very different life cycles assume the same spatial infection pattern in populations of the first intermediate host (Ilyanassa obsoleta) in coastal marsh habitats. Infected snails are disproportionately recovered from intertidal panne habitats, which offer more hospitable environs for snails than do adjacent habitats (intertidal creeks, coastal flats, and subtidal creeks), in terms of protection from turbulence and wave action, as well as the availability of food stuffs. Snails in intertidal panne habitats are of higher quality when assessed in terms of average size-specific mass, growth rate, and fecundity. In mark-recapture experiments, snails frequently dispersed into intertidal pannes but were never observed leaving them. In addition, field experiments demonstrate that snails confined to intertidal panne habitats are disproportionately infected by both trematode species, relative to conspecifics confined to adjacent habitats. Laboratory experiments show that infected snails suffer significant energetic losses and consume more than uninfected conspecifics, suggesting that infected snails in intertidal pannes may survive better than in adjacent habitats. We speculate that 1 possible mechanism for the observed patterns is that the life cycles of both trematode species allows them to contact the highest-quality snails in this marsh ecosystem.     

Ovarian and fat body protein concentrations in Ips sexdentatus (Coleoptera: Scolytidae) parasitized by nematodes

The protein concentrations of fat body and ovaries in Ips sexdentatus either uninfected or infected by Parasitaphelenchus sp., P. sexdentati, or Contortylenchus diplogaster were measured at various stages of insect development, from preswarming maturation to the first oviposition (24 hr after mating). Weight variations of the fat body and ovaries in insects infected by C. diplogaster show the same evolution as those observed in uninfected insects, but at a much lower level. Fat body proteins in uninfected insects reach their minimum level during swarming, but they remain fairly constant throughout the maturation of the first egg. After dropping shortly after swarming, the ovarian protein level in such insects increases in two stages during ovarian maturation. The first stage, which corresponds to a slow protein incorporation, takes place during the first 12 hr after mating. During the second stage, i.e., beyond 12 hr, a significant level of proteins is rapidly incorporated into the ovaries. In insects infected by Parasitaphelenchus fat body proteins are reduced and protein incorporation into the ovaries is reduced; Parasitaphelenchus would thus affect at least some proteins required for ovarian maturation in their host. Fat body protein levels are even more affected by C. diplogaster than by Parasitaphelenchus, while incorporation into ovaries seems to be less affected in spite of slower ovarian growth. C. diplogaster might thus essentially act both upon proteins which are not required for the ovarian maturation of their host and upon nonproteinaceous substances that are required for such maturation. Results are discussed in relation to the possible mode of action of parasitic nematodes.     

Observations on the life-cycle and larval morphogenesis of Cooperia fuelleborni (Nematoda: Trichostrongyloidea) parasitic in impala, Aepyceros melampus

The previously unknown life-cycle of Cooperia fuelleborni, parasitic in impala, is described. The morphology of the developmental stages are compared to those of other Cooperia spp. The similarity between C. fuelleborni and C. curticei is discussed as well as the differences between those two species. The morphological studies showed that C. fuelleborni is closely related to C. curticei of sheep, but also has some affinity with the cattle parasite C. punctata and C. oncophora.     

Eimeria Spp.: Influence of coccidia on digestion (amylolytic activity) in broiler chickens

Loss in pancreatic weight and an overall decrease in amylolytic activity in the pancreas were seen in broiler chickens infected with Eimeria acervulina, E. maxima, and E. necatrix. Only E. acervulina and E. maxima reduced amylolytic activity in the surface mucosa of the regions they infected. Surface-bound amylolytic activity decreased as the severity of infection (as measured by lesion score) with E. acervulina increased. This decrease in activity was not related to the decreased feed consumption in infected birds. Little decrease in amylase activity was found in the lumenal contents with the exception of E. acervulina in the jejunum. When the effect of pH on enzyme activity was studied in vitro, a marked reduction in amylolytic activity was observed as the pH went below 5.0.     

Nest defence by Magpies(Pica pica) and the brood parasitic Great Spotted Cuckoos(Clamator glandarius) in parasitized and unparasitized nests

Summary Nest defence is a frequent and widespread parental behaviour which enhances brood survival. We have found that in a Spanish Magpie population which is heavily parasitized by the brood parasitic Great Spotted Cuckoo, Magpies defend (1) unparasitized more frequently than parasitized nests, and (2) at the end of the nestling period more frequently than in other stages of the breeding cycle. Great Spotted Cuckoos are brood parasites, which means that their eggs are incubated and their nestlings are raised by members of a host species. Brood parasites are not thought to take care of their own offspring. However, we have found that Great Spotted Cuckoos sometimes scolded us on our regular visits to parasitized magpie nests (but never on those to unparasitized nests). Frequency of nest defence by cuckoos differed significantly among years, being significantly higher at the beginning of the study. Although sporadic observations of adult brood parasites feeding juveniles have been recorded, nest defence has not previously been suggested for any brood parasite.

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Nestverteidigung von durch den Häherkuckuck(Clamator glandarius) parasitierten und unparasitierten Nestern bei Elstern(Pica pica)

Zusammenfassung Nestverteidigung ist ein häufiges und weit verbreitetes elterliches Verhalten zur Erhöhung des Bruterfolges. In einer spanischen Elsterpopulation, die sehr intensiv vom Häherkuckuck parasitiert ist, wurden unparasitierte Nester häufiger verteidigt als parasitierte, und zum Ende der Nestlingsperiode wurden Nestern häufiger verteidigt als zu früheren Phasen des Brutzyklus. Häherkuckucke sind Brutparasiten, deren Eier von den Wirtseltern bebrütet und die Nestlinge von ihnen aufgezogen werden. Solche Brutparasiten kümmern sich im allgemeinen nicht selbst um ihre Nachkommen. Manchmal jedoch haßten Häherkuckuck auf uns, wenn wir parasitierte Nester der Elster kontrollierten, während an unparasitierten Nestern ein solches Hassen niemals erfolgte. Die Häufigkeit dieser Nestverteidugung der Kuckucke variierte zwischen Jahren und war signifikant häufiger zu Beginn unserer Untersuchung. Zwar wurde gelegentlich schon Füttern der Jungvögel durch elterliche Brutparasiten beobachtet, die hier festgestellte Nestverteidung ist bisher aber von keinem Brutparasiten beschrieben.

     

Olencira praegustator (Crustacea, Isopoda, Cymothoidae) parasitic on Brevoortia species (Pisces, Clupeidae) from the southeastern coasts of North America: review and re-description

The cymothoid isopod Olencira praegustator (Latrobe, 1802), the sole species of the genus Olencira Leach, 1818, has been the subject of several previous studies, but has remained incompletely described. This species is re-described and figured from the Atlantic menhaden Brevoortia tyrannus (Latrobe, 1802), the type host from the estuarine systems of the South Carolina coast, USA. The general morphology, mouthparts and appendages of the female, male and other stages of its lifecycle are described.

The geographical distribution and hosts recorded for O. praegustator are reviewed. Biological data are summarized and discussed. Areas that need additional studies include the infection process and the effect of the parasite on its host.     

Host and site selection by larval stages and adults of the parasitic copepod Lernaeenicus sprattae (Sowerby) (Copepoda,Pennellidae) in the Oslofjord

Sprat caught by beach seining during the period 1977–1980 were examined for adult Lernaeenicus, and both sprat and herring caught in 1981–1983 were examined for all parasitic stages. Lernaeenicus was never found on herring. Adult L. sprattae were always found in the sprat's eye, usually (89%) in the upper rear quadrant of the eye. Double and triple infection of one or both eyes were found. Infection experiments support results from field work. The sprat is the only intermediate and final host of L. sprattae. In laboratory experiments, copepodites showed no preference for particular size groups of sprat. The infective stages, copepodid and adolescent female, are both initially randomly distributed on the host before the copepodites move towards the fins and the gravid females to the eye.     

G(olf) protein levels in rat striatum are increased by chronic antidepressant administration and decreased by olfactory bulbectomy

There are many studies of the mechanisms of antidepressants; however, most of these studies were conducted on the hippocampus or frontal cortex. In the present study, we hypothesized that the nucleus accumbens and caudate/putamen might be major targets for antidepressant effects. Thus, we focused on G(olf) protein, a stimulant alpha-subunit of G protein that is coupled with the dopamine D1 receptor and specifically expressed in the striatum (nucleus accumbens, caudate/putamen and olfactory tubercle) in the rat brain. We examined the effects of chronic administration of imipramine, fluvoxamine, maprotiline and, as a negative control, cocaine on the level of G(olf) protein in the rat striatum. We also examined the effect of olfactory bulbectomy. Chronic imipramine treatment (10 mg/kg for 2 or 4 weeks) significantly increased the level of G(olf) in the striatum (by 17% or 18%, respectively), although this increase was not apparent after only 1 week of treatment. The time course of these changes corresponded well to that of the clinical efficacy of imipramine. Chronic fluvoxamine and maprotiline treatment (20 mg/kg for 2 weeks) also significantly increased the level of G(olf) (by 9% and 25%, respectively), but cocaine did not alter it significantly. Bulbectomy decreased the G(olf) protein level by 9%. The increases in G(olf) protein after chronic administration of these three different classes of antidepressants and the decrease after bulbectomy suggest that G(olf) protein may play an important role in the antidepressant effect.     

Morphofunctional changes of the digestive gland in the bivalve mollusk Crenomytilus grayanus (Dunker, 1853) in normal conditions and after parasitic invasion by trematodes

Specifics of the digestive cycle were studied in normal individuals of Gray’s mussel Crenomytilus grayanus and in those infested by trematodes from an unpolluted area of the sublittoral zone of Peter the Great Bay in May (during the day), June, July, and August. Four types of tubules corresponding to four phases of the digestive cycle were identified, and three varieties of destructing tubules were distinguished. It was shown that normally phases of absorption and digestion prevailed in the digestive gland. The portion of absorptive tubules (type II) was 95% in spring and 79% in summer. The total portion of destructing and restoring tubules (types III and IV) did not exceed 10% in spring and 20% in summer, and portion of tubules at the initial condition (type I) was 4% in spring and 2% in summer. During the day, insignificant variations in the ratio of different type tubules were recorded. It was revealed that, normally, granulocytomes were formed during utilization of necrotic tubules. Parasitic invasion of trematodes entailed swelling of the gland and a change in the proportion of tubules: the number of absorptive tubules decreased to 20%, the number of destructing and restoring tubules increased up to 60% and 12%, respectively.     

Studies on the characteristics of parasitism ofPlutella xylostella (Lep.: Plutellidae) by a larval parasiteDiadegma semiclausum (Hym.: Ichneumonidae)

Laboratory experiments were conducted to study the characteristics of parasitism of diamondback moth,Plutella xylostella (L.), a worldwide pest of crucifers, by a larval parasite,Diadegma semiclausum Hellén. Results showed that the greater the host larval density, the lesser was the percentage of larvae parasitized. The area of discovery decreased with increasing parasite density, but k-value remained practically unchanged. Parasitism reduced food consumption in parasitised larvae. No difference was observed in duration of larval instars between the parasitized and healthy larvae. As the frequency of superparasitism increased, the proportion of production of female progeny also increased. Presence of parasite larva within the host larva deterred superparasitism greater than the presence of parasite egg. Presence of larva of eitherD. semiclausum or another larval parasite,Cotesia plutellae Kurdjumov, within host larva deterred multiparasitism by either species greater than the presence of egg of either parasite species.Diadegma semiclausum was much more aggressive thanC. plutellae in parasitisingP. xylostella larvae.     

Analysis of serum heat shock protein 70 (HSPA1A) concentrations for diagnosis and disease activity monitoring in patients with rheumatoid arthritis

Heat shock proteins (HSPs) have been repeatedly implicated in the pathogenesis of rheumatoid arthritis (RA). The authors aimed to study applicability of heat shock protein 70 (HSPA1A) serum levels as a diagnostic factor and a severity indicator in patients with RA and to quantify cut-off point that predicts status of RA with highest specificity. A total of 76 patients with RA and 36 healthy adults were studied in this case-control analysis. Patients had a higher HSPA1A level than the control group (0.78 ± 0.13 vs. 0.12 ± 0.02 ng/mL, p = 0.006), irrespective of presence of absence of rheumatoid factor or anti-citrullinated cyclic peptide. Next, diagnostic accuracy of the HSPA1A in diagnosis of RA was evaluated (area under curve 0.71; p < 0.05). HSPA1A predicted status of having RA in levels above 0.42 ng/mL with more than 90 % specificity. In addition to diagnostic value, HSPA1A can distinguish between high disease activity (1.66 ± 0.75 ng/mL) and low (0.49 ± 0.1 ng/mL), moderate (0.52 ± 0.12 ng/mL), or remission phase (0.48 ± 0.11 ng/mL). Moreover, patients in remission still had a higher HSPA1A level compared to normal subject (0.48 ± 0.11 vs. 0.12 ± 0.02 ng/mL, p < 0.05). Our results showed that serum HSPA1A could be implemented as a specific tool to facilitate diagnosis and monitoring disease activity in patients with rheumatoid arthritis.

Electronic supplementary material

The online version of this article (doi:10.1007/s12192-015-0578-z) contains supplementary material, which is available to authorized users.     

Oesophagostomum dentatum: effect of glutathione S-transferase (GST) inhibitors on GST activity and larval development

Sulphobromophthalein (SBP) inhibits isolated glutathione S-transferase of the porcine nodule worm Oesophagostomum dentatum (Od-GST) and reduces larval development in vitro. In this study possible inhibitory effects of various inhibitors were evaluated in an enzymatic (CDNB) assay with isolated Od-GST and in a larval development assay (LDA). Reversibility was tested in the LDA by removing the inhibitor from culture halfway through the cultivation period. SBP, indomethacin and ethacrynic acid inhibited both enzyme activity and larval development in a dose-dependent and reversible manner. HQL-79 also reduced larval development but had only a minor effect on the isolated enzyme. The phospholipase A₂ inhibitors dexamethasone and hydrocortisone had no major effect. High thermal stability of Od-GST was demonstrated with increasing activity between 4 and 50 °C. Differences between Od-GST and GST of other organisms indicate structural and possibly functional peculiarities and highlight the potential of such enzymes as targets of intervention.     

Energy and water balance in the lesser double-collared sunbird (Nectarinia chalybea) feeding on different nectar concentrations

The water balance of nectarivores is tightly linked to their energy balance. When nectar is dilute, consumption of a large water excess is inevitable. We investigated energy and water balance in lesser double-collared sunbirds, Nectarinia chalybea (8 g), kept at 20 °C and fed different nectar concentrations (0.4, 0.8 M sucrose or 1.2 M sucrose). The mass of sucrose consumed, body mass, day-time mass gain and night-time mass loss were the same irrespective of diet, the birds compensating energetically for changes in sucrose concentration by drinking greater volumes of the more dilute solutions. Sunbirds consumed between 0.5 times and 1.8 times their body mass in preformed water per day, depending on sucrose concentration, and excreted around 75% of the water. The difference between water gain (preformed and metabolic water) and excreted water is assumed to equal evaporative water loss, and was similar on 1.2 M and 0.8 M sucrose, but was higher on a diet of 0.4 M sucrose. The osmolalities and K⁺ and Na⁺ concentrations of the excreted fluid were extremely low, so that sunbird urine resembled that of hummingbirds and freshwater vertebrates rather than that of typical terrestrial vertebrates. N. chalybea is able to maintain energy and water balance over a range of nectar concentrations by adjusting the volume of solution consumed and by excreting copious, dilute fluid. Accepted: 2 January 1999     

Increased circulating heat shock protein 70 (HSPA1A) levels in gestational diabetes mellitus: a pilot study

Recent data indicate that serum Hsp70 (HSPA1A) levels are increased in type 1 and 2 diabetes mellitus. However, there is no report in the literature on circulating Hsp70 levels in gestational diabetes mellitus. In this pilot study, we measured serum Hsp70 levels in 11 pregnant women with pregestational diabetes, 38 women with gestational diabetes, and 40 healthy pregnant women with ELISA. Plasma glucose levels, serum insulin concentrations, HbA1c values, and the Homeostatic Model Assessment-Insulin Resistance (HOMA-IR) index were also determined. According to our results, serum Hsp70 concentrations were significantly higher in women with pregestational and gestational diabetes mellitus than in healthy pregnant women. In addition, pregestational diabetic women had significantly higher Hsp70 levels than those with gestational diabetes. Furthermore, in the group of women with gestational diabetes mellitus, serum Hsp70 levels showed a significant positive correlation with HbA1c values. However, there was no other relationship between clinical features and metabolic parameters of the study subjects and their serum Hsp70 levels in either study group. In conclusion, we demonstrated for the first time in the literature that serum Hsp70 levels are increased and correlate with HbA1c values in women with gestational diabetes mellitus. Nevertheless, further studies are needed to determine whether circulating Hsp70 plays a causative role in the pathogenesis of gestational diabetes or elevated serum Hsp70 levels are only consequences of the disease.     

Acquired TRAIL resistance in human breast cancer cells are caused by the sustained cFLIP(L) and XIAP protein levels and ERK activation

We established TRAIL-resistant MDA-231/TR cells from MDA-231 parent cells to understand the mechanism of TRAIL resistance in breast cancer cells. The selected TRAIL-resistant cells were cross-resistant to TNF-alpha/cycloheximide but remained sensitive to DNA-damage drugs such as oxaliplatin and etoposide. The expression levels of death receptors (DR4 and DR5), FADD, cIAP1, cIAP2, and Bcl-2 family were not changed in TRAIL-treated both cells. Significant down-regulation of XIAP and cFLIP was occurred after TRAIL treatment in MDA-231 cells whereas their levels were sustained in MDA-231/TR cells. TRAIL-mediated activation of ERK and JNK were also observed in parent MDA-231 cells but not in MDA-231/TR cells. However, TRAIL-resistant cells showed constitutive activation state after treatment with TRAIL. Pretreatment with PD98059 or transfection of MKK1-DN (dominant negative) expression vector attenuated TRAIL resistance in MDA-231/TR cells. Our findings provide the evidence that the sustained expression level of cFLIP(L) and XIAP protein and constitutive ERK activation may lead to acquired TRAIL resistance in breast cancer cells.     

Differences in heat shock protein 70 expression during larval and early spat development in the Eastern oyster, Crassostrea virginica (Gmelin, 1791)

For a variety of species, changes in the expression of heat shock proteins (HSP) have been linked to key developmental changes, i.e., gametogenesis, embryogenesis, and metamorphosis. Many marine invertebrates are known to have a biphasic life cycle where pelagic larvae go through settlement and metamorphosis as they transition to the benthic life stage. A series of experiments were run to examine the expression of heat shock protein 70 (HSP 70) during larval and early spat (initial benthic phase) development in the Eastern oyster, Crassostrea virginica. In addition, the impact of thermal stress on HSP 70 expression during these early stages was studied. C. virginica larvae and spat expressed three HSP 70 isoforms, two constitutive, HSC 77 and HSC 72, and one inducible, HSP 69. We found differences in the expression of both the constitutive and inducible forms of HSP 70 among larval and early juvenile stages and in response to thermal stress. Low expression of HSP 69 during early larval and spat development may be associated with the susceptibility of these stages to environmental stress. Although developmental regulation of HSP 70 expression has been widely recognized, changes in its expression during settlement and metamorphosis of marine invertebrates are still unknown. The results of the current study demonstrated a reduction of HSP 70 expression during settlement and metamorphosis in the Eastern oyster, C. virginica.     

Seasonal modulation of plasma antifreeze protein levels in Atlantic (Anarhichas lupus) and spotted wolffish (A. minor)

The Atlantic and spotted wolffish (Anarhichas lupus and A. minor, respectively) inhabit the cold waters of the northeast Atlantic Ocean. Although both species experience subzero water temperatures during winter, the Atlantic wolffish, which occupies shallower waters than the spotted wolffish, faces the greater threat of coming into contact with ice and freezing. This laboratory study was designed to determine whether these species differed in their abilities to resist freezing by examining the seasonal changes in blood plasma freezing points, antifreeze protein (AFP) activity and Na⁺ and Cl⁻ concentrations when exposed to seasonally cycling water temperatures and photoperiod. The plasma of both species showed distinct seasonal cycles in all parameters with the highest values occurring during the winter. However, of the two species, only the Atlantic wolffish produced sufficient AFP to protect the fish down to the freezing point of seawater (− 1.80 °C). The levels of AFP in the spotted wolffish were too low to impart any significant improvement in their resistance to freezing (approximately − 0.8 °C).When wolffish were maintained in warm water under a seasonally changing photoperiod, the amplitude of the seasonal cycle in AFP activity was greatly reduced, indicating that low water temperatures are necessary to maximize plasma AFP levels. However, despite being maintained in warm water, plasma levels of AFP activity began to increase over summer values at the same time of year as did the fish exposed to seasonally changing water temperatures. This suggests that photoperiod plays a major role in the timing of the annual AFP cycle.