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1.
Pest Manag Sci ; 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38940484

ABSTRACT

BACKGROUND: The olive fruit fly (OFF), Bactrocera oleae (Rossi), is the main insect pest of olive trees worldwide. Legislation limits to the use of some synthetic larvicidal insecticides is leading to the development of new control options for preventive control of adult flies. In the present study, the biological activity of four short-chain aliphatic aldehydes, namely hexanal, (E)-2-hexenal, heptanal and (E)-2-heptenal, previously reported as repellents to the OFF adults was investigated. RESULTS: Electroantennography (EAG) recordings showed that antennae of OFF males and females are able to perceive the test compounds in a wide range of doses. In field trapping experiments, reservoir-type polypropylene (PP) membrane dispensers loaded with individual compounds did not elicit a significant attraction of OFF males and females. On the contrary, a significant reduction of male catches was noticed when sex pheromone dispensers and PP membrane dispensers, loaded with one of the test compounds, were applied on the same white sticky traps ≈20 cm apart. Likewise, male and female catches in yellow sticky traps baited with ammonium carbonate (AC) dispensers as food attractant were significantly reduced by the presence of PP membrane dispensers of individual aliphatic aldehydes on the same traps. In small plots control trials, solid formulations of the four aldehydes into a bentonite clay support induced a significant reduction of the OFF active infestation mainly when C6 and C7 aldehyde-activated bentonites were used. CONCLUSION: Short-chain aliphatic aldehydes showed inhibitory effects on sex pheromone and food attractant-mediated attraction of OFF. Results of field trials suggest potential of short-chain aliphatic aldehydes to develop new semiochemical-based OFF control options. © 2024 Society of Chemical Industry.

2.
J Chem Ecol ; 2024 May 20.
Article in English | MEDLINE | ID: mdl-38767818

ABSTRACT

Chemical, electrophysiological, and field trapping experiments were carried out to identify the female-produced sex pheromone of the asparagus moth, Parahypopta caestrum, a very serious pests of asparagus cultivations in southern Europe. Gas chromatography coupled with mass spectrometry and electroantennogram detection (GC-MS-EAD) analysis of hexane and solid-phase microextraction (SPME) extracts of sex pheromone glands of calling females consistently detected four compounds eliciting EAG responses in male moth antennae. According to their GC retention times, mass spectra, and comparative EAG analyses with reference standards, these EAD-active compounds were identified as (Z)-9-tetradecenol (Z9-14:OH), (Z)-5-tetradecenyl acetate (Z5-14:Ac), (Z)-7-tetradecenyl acetate (Z7-14:Ac), and (Z)-9-tetradecenyl acetate (Z9-14:Ac), respectively. In the SPME extracts from the head-space of individual abdominal tips, Z9-14:Ac, Z5-14:Ac, Z7-14:Ac, and Z9:14 OH were detected in the ratio of 82:9:5:4. In EAG dose-response experiments, Z9-14:Ac was the strongest antennal stimulant at different doses tested. In field trapping experiments, Z9-14:Ac, Z7-14:Ac, and Z5-14:Ac proven to be essential for male attraction and a their 85:5:10 blend loaded onto green rubber septum dispensers was significantly more effective than single-, two-, and any other three-component blend of these compounds. The addition of Z9-14:OH to the optimal blend resulted in a significant reduction of male catches. The attractive blend here identified allowed for an effective and accurate monitoring of P. caestrum flight activity in southern Italy.

3.
Sci Rep ; 13(1): 14246, 2023 08 30.
Article in English | MEDLINE | ID: mdl-37648729

ABSTRACT

The granary weevil (Sitophilus granarius L.) is a major primary pest of stored cereals throughout the world. Among the major classes of plant secondary metabolites, flavonoids can affect insect feeding behaviour and their growth rate. In this study, the susceptibility of an anthocyanin-rich purple durum wheat genotype (T1303) to the granary weevil was evaluated in comparison with two yellow durum (Ofanto) and bread (Mec) wheat varieties. The feeding response and food utilisation efficiency by adult insects was also investigated by calculating nutritional indices in whole flour disk bioassays. Different levels of susceptibility to granary weevil emerged among genotypes tested. The mean food consumption by an insect, F1 progeny, and female parental offspring calculated for the T1303 genotype were significantly lower than those of yellow kernel wheat varieties. Moreover, T1303 genotype induced deterrence in the adult insects as demonstrated by the positive values of the food deterrence index. Besides, relative grow rate and efficiency conversion of ingested food indices were negative for T1303 and positive for both yellow wheat varieties indicating respectively a decrease and an increase of insect body weight during the bioassays. Finally, a higher mortality rate was recorded for insects fed on T1303 flour disks compared to disks obtained from yellow wheat varieties. These results provide evidence for the antifeedant and toxic effects of anthocyanins present in the T1303 pericarp against the granary weevil. Overall, this study contributes new insights into the mechanisms of host acceptance and food utilization by S. granarius and would be useful to identify antifeedant flavonoids as well as to develop varietal resistance-based strategies against this pest.


Subject(s)
Triticum , Weevils , Animals , Triticum/genetics , Weevils/genetics , Anthocyanins/pharmacology , Bread , Flavonoids/pharmacology , Genotype
4.
Zootaxa ; 5230(2): 209-224, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-37044848

ABSTRACT

Neocarus platensis is redescribed from part of the syntype series collected in Argentina and lectotype specimens are designated. The remaining syntype material from Uruguay represents a new species, herein named Neocarus paraplatensis sp. nov. Taxonomic problems within the Opilioacaridae are discussed in light of a comparative morphological discussion including setae quantity variation.


Subject(s)
Acari , Animals
5.
Arthropod Struct Dev ; 63: 101057, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34022513

ABSTRACT

The genera Daidalotarsonemus De Leon and Excelsotarsonemus Ochoa & Naskrecki are mainly characterized, in the females, by the presence of sculpturing on the dorsal shields and by highly modified dorsal setae, greatly enlarged, laminar or sail-shaped. Moreover, both genera are characterized by abundant cerotegument all over the body and on the modified setae (d, e, f) with the presence of fungi, lichens, and bacteria accumulating. The peculiar morphology of the dorsal setae in these two genera has suggested they might have other functions beside the sensory one. Ultrastructural observations using scanning and transmission electron microscopy techniques revealed that, albeit extravagantly modified, these dorsal setae should act as mechanoreceptors in agreement with most of the previous observations in mites. The morphological modifications of the setae d, e, and f (pronounced cup shape of setae e and enlarged shaft with concave longitudinal strips of setae d and f) suggest they play, in addition to the tactile function, a storage role and dispersive role for fungal spores collected by the mite while moving in the humid environment. Moreover, the modified setae d, e, and f inserted on elevated sockets are probably movable by the action of dorso-ventral muscles; thus, mites might use their sail-shape to become airborne. In addition, the body dorso-ventral muscles observed inserting close to the elevated seta e sockets suggest the mite might also lift these cup-like setae to spread the fungal particles on the body or over adjacent vegetation as well. Biological and feeding studies are necessary to better understand the role such fungi might play in the mite life cycle.


Subject(s)
Mites , Sensilla , Animals , Female , Mechanoreceptors , Microscopy, Electron, Transmission
6.
Arthropod Struct Dev ; 60: 101023, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33401135

ABSTRACT

The setae of mites are not regarded as secretory structures, yet in the flat mite genus Raoiella, each developmental stage presents droplets of fluid associated with the tips of their dorsal setae. To understand the origin of this fluid, the ultrastructure of the dorsal setae is investigated in females of Raoiella bauchani Beard & Ochoa and the invasive pest species Raoiella indica Hirst using scanning and transmission electron microscopy techniques. The dorsal setae are barbed along their entire length and have either a broadened plumose or a flat spatulate tip. Ultrastructurally, they present the typical features of mechanoreceptors, but have a "hollow" axis represented by a protoplasmatic core containing dendritic branches. This combination of ultrastructural characters indicates that the setae might be multimodal receptors: acting as both mechanoreceptors and contact chemoreceptors. The epidermal cells that underlie the setal sockets are columnar and have an ultrastructure that suggests they have a glandular function. Moreover, these cells present regular microvilli apically and form extracellular cuticular canals, containing epicuticular filaments, that are connected with the microvilli proximally and which open via pores onto the surface of the setal base distally. This arrangement indicates that the secretion from the microvilli passes into the canals and is then conducted to pores at the base of the seta, where it then accumulates and moves up the setal shaft, along the longitudinal grooves of the barbs. Based on similar arrangements in some insect taxa, the organization of the structures here observed in Raoiella suggests the passage of a non-polar, water insoluble, lipoid fluid through the cuticle, the function of which is still obscure.


Subject(s)
Mites/ultrastructure , Sensilla/ultrastructure , Animals , Chemoreceptor Cells/ultrastructure , Female , Mechanoreceptors/ultrastructure , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Species Specificity
7.
Exp Appl Acarol ; 81(4): 531-546, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32748183

ABSTRACT

The genus Brevipalpus (Tenuipalpidae) includes 291 described species commonly found in the tropical and subtropical regions. Morphological characters considered in the taxonomy of Brevipalpus species are difficult to discern, which often leads to erroneous identifications and the presence of cryptic species within species is suspected. New morphological characters are now considered relevant for identification of Brevipalpus species; among them, the morphology of the seminal receptacle (spermatheca) of the female insemination system. This feature has not been considered relevant until now; thus, there is little information about the insemination system in the available species descriptions. Hence, in the present study, ultrastructural details are provided for the insemination system in five species of Brevipalpus, representing different morphological groups. The seminal receptacle (spermatheca) and the insemination duct are illustrated using light, transmission and scanning electron microscopy. The spermatheca proved to have specific morphological features that can be useful for taxonomic purposes. On the other hand, its appearance within a population might be variable in a way that needs to be ascertained and evaluated.


Subject(s)
Mites/anatomy & histology , Mites/physiology , Animals , Female , Insemination , Mites/ultrastructure
8.
Antioxidants (Basel) ; 8(12)2019 Dec 13.
Article in English | MEDLINE | ID: mdl-31847149

ABSTRACT

BACKGROUND: Caloric restriction is a valid strategy to reduce the visceral adipose tissue (VAT) content in obese persons. Hypocretin-1 (orexin-A) is a neuropeptide synthesized in the lateral hypothalamus that strongly modulates food intake, thus influencing adipose tissue accumulation. Therapeutic diets in obesity treatment may combine the advantages of caloric restriction and dietary ketosis. The current study aimed to evaluate the effect of a very low calorie ketogenic diet (VLCKD) in a population of obese patients. METHODS: Adiposity parameters and orexin-A serum profiling were quantified over an 8 week period. The effect of the VLCKD on reactive oxygen species (ROS) production and cell viability was evaluated, in vitro, by culturing Hep-G2 cells in the presence of VLCKD sera. RESULTS: Dietary intervention induced significant effects on body weight, adiposity, and blood chemistry parameters. Moreover, a selective reduction in VAT was measured by dual-energy X-ray absorptiometry. Orexin-A levels significantly increased after dietary treatment. Hep-G2 cell viability was not affected after 24, 48, and 72 h incubation with patients' sera, before and after the VLCKD. In the same model system, ROS production was not significantly influenced by dietary treatment. CONCLUSION: The VLCKD exerts a positive effect on VAT decrease, ameliorating adiposity and blood chemistry parameters. Furthermore, short-term mild dietary ketosis does not appear to have a cytotoxic effect, nor does it represent a factor capable of increasing oxidative stress. Finally, to the best of our knowledge, this is the first study that shows an effect of the VLCKD upon the orexinergic system, supporting the usefulness of such a therapeutic intervention in promoting obesity reduction in the individual burden of this disease.

9.
PLoS One ; 14(9): e0223058, 2019.
Article in English | MEDLINE | ID: mdl-31553779

ABSTRACT

Several heart rate variability (HRV) studies show abnormalities in autonomic nervous control in obese and overweight subjects. However, some of the results appear to be controversial. Here we investigate the HRV profile in seventy adult normotensive women and its association with general and visceral adiposity. Specifically, we recorded the electrocardiographic (ECG) activity in subjects during a supine resting state for five minutes in a quiet room late in the morning. Total fat mass (TFM) and visceral adipose tissue (VAT) were instead estimated using dual-energy X-ray absorptiometry (DXA). Finally, we used simple a linear regression analysis of frequency and time-domain parameters to study the relationship between HRV and adiposity. Our data showed an overall reduction of the HRV related to an increase of TFM although this regression appeared significant only for high frequencies (HF). When the linear regression was applied between HRV variables and VAT, the slope of the line increases, thus unveiling a statistically significant relation (i.e. the more VAT, the lower HRV). Finally, a control analysis showed that age does not alter the relation between HRV and VAT when used as a confounding factor in multiple regression. To conclude, these findings point to abnormal activity of the autonomic nervous system (ANS) in subjects with an excess of VAT and represent a starting point to determine a non-invasive index of cardiac wellness for clinical and nutritional application.


Subject(s)
Adiposity/physiology , Autonomic Nervous System/physiopathology , Biological Variation, Individual , Heart Rate/physiology , Heart/physiopathology , Absorptiometry, Photon , Adult , Body Mass Index , Electrocardiography , Female , Healthy Volunteers , Humans , Intra-Abdominal Fat/diagnostic imaging , Young Adult
10.
Insects ; 10(9)2019 Aug 27.
Article in English | MEDLINE | ID: mdl-31461927

ABSTRACT

BACKGROUND: The red-necked longhorn beetle, Aromia bungii, is one of the most damaging pests of stone fruit trees. Native to the south-eastern Palearctic and Oriental regions, it invaded and is established to some extent in the Campania Region (Southern Italy). In several cerambycid species, volatile organic compounds (VOCs) have been shown to play a role in mate and host plant location. METHODS: The electroantennographic (EAG) technique was employed to explore the antennal chemoreceptivity of male and female A. bungii antennae to 90 VOCs. RESULTS: Increasing EAG amplitudes from the basal to the distal antennal segments were recorded in response to six selected plant volatiles. From the distal flagellomeres, the largest EAG responses (>0.8 mV) were elicited by 2-hexanol, octanal, sulcatone, guaiacol, sulcatol, 2,4-dimethyl-3-hexanol, 2,4-dimethyl-2-hexanone, heptanal, nonanal, (Z)-3-hexenol, and 1-heptanol in both sexes, and by linalool, (E)-2-heptenal, 1-octen-3-ol, (E)-2-octenal, 3-octanol, (E)-2-octen-1-ol, α-phellandrene, and α-terpinene in males. The olfactory system of both sexes proved to be sensitive to changes in stimulus concentration and compound structure. CONCLUSIONS: this study demonstrates the capability of A. bungii males and females to detect and discriminate among a wide range of VOCs and provides a basis for further olfactometer and field trapping experiments aimed at identifying behaviorally-active compounds useful for the implementation of semiochemical-based control strategies for this pest.

11.
Avian Pathol ; 48(sup1): S10-S16, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31012743

ABSTRACT

Scanning electron microscopy observations of the distal leg region of the poultry red mite Dermanyssus gallinae (De Geer 1778) identified the presence of a compound ambulacrum, the part of the leg that contacts the substratum when the mite walks. The ambulacrum is comprised of a praetarsus (the ambulacrum stalk), a pulvillus and two claws. The pulvillus is a weakly sclerotized structure that can be partly expanded or retracted in the praetarsus. When expanded, the pulvillus shows a cushion-like shape which can, as a result of its soft surface, function as a sucker, thus allowing D. gallinae to adhere to a smooth surface. When traversing an irregular surface, or clinging to a soft surface, the mite retracts the pulvillus and uses only its strongly sclerotized movable claws. These observed morphological adaptations explain the ability of D. gallinae to climb upwards on a slippery surface, resist an air flux, walk on smooth and rigid feathers of its avian hosts, and cling to the bird's or human's soft skin. This knowledge is important to better understand the attachment mechanism of this species to its host and to the substratum on which it moves, and also to provide insight into the circumstances under which it is able to move. RESEARCH HIGHLIGHTS The ambulacrum is the distal part of the leg touching the substratum D. gallinae's ambulacrum consists of a praetarsus, a pulvillus and two claws The weakly sclerotized pulvillus can be part expanded/retracted in the praetarsus The expanded pulvillus functions as a sucker to adhere to smooth surfaces The claws are used to walk on an irregular surface or cling to a soft surface.


Subject(s)
Mite Infestations/veterinary , Mites/anatomy & histology , Poultry Diseases/parasitology , Animals , Feathers/parasitology , Female , Male , Microscopy, Electron, Scanning , Mite Infestations/parasitology , Mites/physiology , Poultry , Walking
12.
Insects ; 10(4)2019 Mar 28.
Article in English | MEDLINE | ID: mdl-30925753

ABSTRACT

BACKGROUND: It has been proved that chemical signals play an important role in mating location and reproductive behavior in cerambycids; moreover, they rely on contact chemoreception for mate recognition. METHODS: Adult antennae of Aromia bungii were observed using scanning electron microscopy and adult antennal secretions were collected and analyzed with gas chromatography-mass spectrometry. RESULTS: Twelve different types of sensilla were morphologically described on the antennae of A. bungii. At least six mechanoreceptors-one gustative, one putative chemo- or thermoreceptor, and three multiporous olfactory receptors-are present on the antennae of both sexes while a receptor-type of unclear function is limited to males. Secretions associated with sensilla basiconica were observed for the first time in a cerambycid species. CONCLUSIONS: Sensilla basiconica should play a role in odor perception detecting host tree volatiles and/or pheromones. Sensilla basiconica type 1 and 2 produce a viscous material accumulating on the antennal surface. Chemical analysis of adult antennal secretions highlighted marked differences between sexes. Some of the identified compounds have been previously reported as contact pheromone components of other cerambycid species. Our observations strongly suggest sensilla basiconica as the production sites of compounds involved in mate recognition.

13.
Vet Dermatol ; 2018 Apr 30.
Article in English | MEDLINE | ID: mdl-29708634

ABSTRACT

BACKGROUND: Dermanyssus gallinae is a major threat for the poultry industry; these mites also feed on the blood of many other birds, small mammals and potentially humans. HYPOTHESIS/OBJECTIVES: Three cats with dermatitis attributed to D. gallinae infestation. ANIMALS: Two 40-day-old kittens, living in a rural area, and one 7-year-old female indoor cat, were presented with a pruritic skin condition. METHODS: Mite specimens were collected from the cats and examined by light and scanning electron microscopy. Cytological and histological examinations of the skin lesions were performed. RESULTS: A diagnosis of D. gallinae infestation was made after identification of the mites. Histological findings were compatible with eosinophilic dermatitis. Clinical improvement was noted two weeks after treatment. CONCLUSIONS AND CLINICAL IMPORTANCE: The two kittens showed chronic blood loss which reflects the ability of D. gallinae mites to switch host. For the indoor cat, mites were presumed to be carried by birds regularly present on the balcony of the apartment. This demonstrates that mite infestation is possible even in urban areas, through contact with birds or their abandoned nests. When birds are not present, cats or other small mammals as well as humans, can be infested.

14.
PLoS One ; 12(12): e0190454, 2017.
Article in English | MEDLINE | ID: mdl-29287108

ABSTRACT

The meadow spittlebug, Philaenus spumarius L. (Hemiptera, Aphrophoridae) is a commonly found vector of Xylella fastidiosa Wells et al. (1987) strain subspecies pauca associated with the "Olive Quick Decline Syndrome" in Italy. To contribute to the knowledge of the adult P. spumarius chemoreceptivity, electroantennographic (EAG) responses of both sexes to 50 volatile organic compounds (VOCs) including aliphatic aldehydes, alcohols, esters, and ketones, terpenoids, and aromatics were recorded. Measurable EAG responses were elicited by all compounds tested. In both sexes, octanal, 2-octanol, 2-decanone, (E)-2-hexenyl acetate, and vanillin elicited the strongest antennal amplitude within the chemical groups of aliphatic saturated aldehydes, aliphatic alcohols, aliphatic acetates and aromatics, respectively. Male and female EAG responses to sulcatol, (±)linalool, and sulcatone were higher than those to other terpenoinds. In both sexes, the weakest antennal stimulants were phenethyl alcohol and 2-pentanone. Sexual differences in the EAG amplitude were found only for four of test compounds suggesting a general similarity between males and females in antennal sensitivity. The olfactory system of both sexes proved to be sensitive to changes in stimulus concentration, carbon chain length, and compound structure. Compounds with short carbon chain length (C5-C6) elicited lower EAG amplitudes than compounds with higher carbon chain length (C9-C10) in all classes of aliphatic hydrocarbons with different functional groups. The elucidation of the sensitivity profile of P. spumarius to a variety of VOCs provides a basis for future identification of behaviorally-active compounds useful for developing semiochemical-based control strategies of this pest.


Subject(s)
Arthropod Antennae/physiology , Hemiptera/physiology , Smell/physiology , Volatile Organic Compounds , Animals , Female , Male
15.
ScientificWorldJournal ; 2017: 9064531, 2017.
Article in English | MEDLINE | ID: mdl-28251174

ABSTRACT

In Mediterranean countries, Sarcophaga (Liopygia) crassipalpis, Sarcophaga (L.) argyrostoma, and Sarcophaga (L.) cultellata share the same ecological niche and can be responsible of myiasis. In this study, the main morphological characters of a larva found in a hospitalized woman were described and illustrated by light and SEM microscopy and the features discussed. Then, a fragment within the mitochondrial encoded cytochrome c oxidase subunit I (coxI) gene of ~735 bp was amplified and sequenced. The molecular investigation was necessary to confirm the species Sarcophaga (Liopygia) argyrostoma (99% of identity). Our findings showed that morphological descriptions of larvae of three Mediterranean species of Liopygia available in several papers might not be clear enough to allow for comparison and correct identification. Until results of reliable comparative studies of larvae of all three species will be available, the use of molecular tools is crucial, to avoid misleading or incomplete identification, and in particular when a myiasis becomes a legal issue.


Subject(s)
Myiasis/pathology , Sarcophagidae/classification , Animals , Cyclooxygenase 1/genetics , Female , Genes, Insect , Humans , Larva/anatomy & histology , Larva/classification , Sarcophagidae/anatomy & histology
16.
J Morphol ; 274(8): 918-25, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23650142

ABSTRACT

Many gamasid mites, mainly of the taxon Dermanyssina, possess a secondarily evolved insemination system that is generally described as occurring in two types, the laelapid and the phytoseiid-type, which are structurally considerably different. Considering that Dermanyssina represent the most recent and most diverse group of gamasid mites, it was expected that a greater diversity of insemination system than reflected by the two types could be present and could give an idea of its evolution within the taxon. Here, the authors present a description of the fine-structure of the female secondary insemination system in the dermanyssine mite Hattena cometis. The system consists of a pair of sperm induction pores (solenostomes) and short sperm access ducts (tubules) which end in a syncytium. The syncytial strands of both sides meet medially under the ovary s.str., where they form a spherical syncytial spermatheca. Mature sperm cells of a modified ribbon type were seen in the syncytial parts of the system. The insemination system of Hattena cometis is regarded as a modification of the laelapid type. However, it is much simpler than that of Varroa destructor, the only other gamasid mite with the laelapid type studied ultrastructurally until now, and shows also some structural differences (e.g., no presence of an unpaired sperm duct). Hence, the present study suggests that some intermediate types might be revealed in future ultrastructure studies representing steps in the evolution of the insemination system in the Dermanyssina.


Subject(s)
Mites/ultrastructure , Animals , Female , Insemination , Male , Mites/physiology , Ovary/ultrastructure , Spermatozoa/ultrastructure
17.
J Morphol ; 274(9): 1010-25, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23686457

ABSTRACT

The ameroseiid mite Hattena cometis has a male genital system that consists of an unpaired, u-shaped testis and paired deferent ducts leading into an unpaired accessory genital gland and ejaculatory duct. The genital opening is located anteriorly immediately in front of the sternal shield. Spermatogenesis is simple, probably due to the haploid nature of the male. Eight stages of spermatogenesis could be roughly distinguished. Mature spermatozoa as found in the deferent duct lumen are peculiar in having a bisected nucleus and numerous peripheral flat chambers, which were formed from indentations of the plasmalemma. In inseminated females, spermatozoa were observed in the syncytial tissue of the sperm access system and in the somatic cells of the ovary. These spermatozoa have achieved a new structure, i.e., an electron-dense plate dividing the cell into two unequal halves. The dense plate has an intricate substructure. Its function is unknown. These sperm cells are considered to represent capacitated spermatozoa. The peripheral chambers are reduced in number inside the female. Similar sperm cells, containing a dense plate, were seen in vacuoles within the epithelium of the deferent duct of one male. These cells are evidently under destruction, but before being completely dissolved had undergone a development leading beyond that of the mature sperm cells found in the deferent duct. Apparently, entering the cell of the deferent duct epithelium or the syncytium tissue triggers the production of the dense plate (or the capacitation process). Our observations are compared with results obtained from other anactinotrichid Acari, mainly Gamasida, and confirm and complete the interpretation of the correlated evolution of components of gamasid reproductive systems.


Subject(s)
Mites/ultrastructure , Animals , Ejaculatory Ducts , Genitalia, Male/ultrastructure , Insemination , Male , Mites/physiology , Spermatogenesis/physiology , Spermatozoa/physiology , Spermatozoa/ultrastructure , Testis/ultrastructure
18.
Parasit Vectors ; 5: 104, 2012 May 30.
Article in English | MEDLINE | ID: mdl-22647594

ABSTRACT

BACKGROUND: Dermanyssus gallinae (poultry red mite) is a major threat for the poultry industry and is of significant interest for public health. Identification of D. gallinae can be difficult for scientists not familiar with mite morphology and terminology especially when trying to use identification keys. Moreover, this species may easily be confused with another dermanyssoid mite, Ornithonyssus sylviarum (northern fowl mite), which often shares the same hosts and environment. METHODS: Specimens of D. gallinae were collected at poultry farms in the Puglia and performed for light and scanning electron microscopy observations, identification and micrographs. Moreover specimens of O. sylviarum were collected separately macerated and mounted on slides for light microscopy observations, identification and pictures. RESULTS: The micrographs used in this study, based on LM and SEM observations, highlight the following important identifying characters of D. gallinae: the prominent shoulders of the dorsal shield and the jagged edges of the shield reticulations, the position of setae j1, s1 and the epigynal pores, and the presence on tibia IV pl of one seta. Additional micrographs highlighting the shape of the dorsal (abruptly narrowed posteriorly) and epigynal (narrowly rounded posteriorly) shields and the chelicera (elongate, with distinct digits) of O. sylviarum enable its differentiation from D.gallinae. CONCLUSION: The photographic support provided here (both LM and SEM pictures) can be considered a practical tool for scientists who are not well acquainted with the morphology of D.gallinae, and who are involved with classical and molecular systematics, veterinary and human health aspects of poultry red mites.


Subject(s)
Acari/classification , Acari/ultrastructure , Animals , Female , Larva , Male , Microscopy, Electron, Scanning , Nymph , Species Specificity
19.
Am J Physiol Gastrointest Liver Physiol ; 293(4): G673-81, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17640974

ABSTRACT

PGE2 plays a critical role in colorectal carcinogenesis. We have previously shown that COX-2 expression and PGE2 synthesis are mediated by IGF-II/IGF-I receptor signaling in the Caco-2 cell line and that the pathway of phosphatidylinositol 3-kinase (PI3K)/Akt protects the cell from apoptosis. In the present study, we demonstrate that PGE2 has the ability to increase Ras and PI3K association and decrease the level of apoptosis in the same experimental system. The effect of PGE2 on PI3K/Ras association is dependent on the activation of EP4 receptor, the increase of cAMP levels, and the activation of PKA. In fact, treatment of cells with the PKA inhibitor H89 decreases the association of Ras and PI3K and Ras-associated PI3K activity. PKA inhibitor H89 is able to decrease threonine phosphorylation of Akt and to increase serine phosphorylation of Akt by p38 MAPK and counteracts the cytoprotective effect induced by PGE2. In addition, PGE2 is able to activate p38 MAPK and the inhibition of p38 MAPK, with SB203580 specific inhibitor or with dominant negative MKK6 kinase, is able to revert the apoptotic effect of H89 and serine phosphorylation of Akt. The effect of PGE2 on Caco-2 cell survival through PKA activation is mediated and regulated by the balance of threonine/serine phosphorylation of Akt by p38 kinase and PI3K. In conclusion, our data elucidate a novel mechanism for regulation of colon cancer cell survival and provide evidences for new combinatory treatments of colon cancer.


Subject(s)
Apoptosis/drug effects , Cyclic AMP-Dependent Protein Kinases/physiology , Dinoprostone/pharmacology , Phosphatidylinositol 3-Kinases/physiology , ras Proteins/physiology , Caco-2 Cells , Humans , Imidazoles/pharmacology , Isoquinolines/pharmacology , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Proto-Oncogene Proteins c-akt/physiology , Pyridines/pharmacology , Sulfonamides/pharmacology , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors
20.
Mol Cancer Ther ; 5(5): 1318-24, 2006 May.
Article in English | MEDLINE | ID: mdl-16731765

ABSTRACT

Aspirin displays, at millimolar concentrations, several mechanisms independent from its ability to inhibit cyclooxygenases. Occasionally, the mechanisms displayed in vitro have been clearly related to an effect of clinical relevance in vivo. An expanding literature has been focusing on the cytoprotective effect of aspirin in neurodegenerative disorders and the activation of AKT pathway in neuroprotection and induction of resistance to anticancer drugs. In this work, we tested the ability of aspirin to activate the AKT survival pathway in methylcholanthrene-induced fibrosarcoma cells (Meth A) transplanted into BALB/c nude mice and the clinical effect of aspirin cotreatment during etoposide (VP-16)-based anticancer therapy. We found that cotreatment with aspirin reduced VP-16-induced apoptosis and activated AKT in vitro and in vivo. In Meth A-bearing mice, aspirin administration also activated glycogen synthase kinase-3 and reduced the activity and the efficacy of anticancer therapy in VP-16 cotreated animals. Our data suggest that the antiapoptotic effect of aspirin operates in vivo through the activation of AKT-glycogen synthase kinase pathway causing a decrease in the outcome of VP-16-based therapy. These findings could have clinical relevance in treatment of human malignancies.


Subject(s)
Antineoplastic Agents, Phytogenic/antagonists & inhibitors , Aspirin/pharmacology , Etoposide/antagonists & inhibitors , Glycogen Synthase Kinases/metabolism , Neoplasms, Experimental/drug therapy , Proto-Oncogene Proteins c-akt/metabolism , Animals , Anti-Inflammatory Agents, Non-Steroidal/metabolism , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Antineoplastic Agents, Phytogenic/therapeutic use , Aspirin/metabolism , Etoposide/therapeutic use , Female , Fibrosarcoma/chemically induced , Fibrosarcoma/metabolism , Methylcholanthrene , Mice , Mice, Inbred BALB C , Neoplasm Transplantation , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction/drug effects , Time Factors , Tumor Cells, Cultured
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