Cytochemical study of Rhodnius neglectus and Rhodnius prolixus salivary gland cells (Hemiptera, Triatominae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Female paraurethral prostate gland in Bitches

Even though the presence of the female prostate has been reported in many species, including humans, bats and several rodents, it has many anatomical and histological variations. There is still plentiful discussion on the biological function of this organ. Many authors state that paraurethral ducts and glands are functional and homologous to the male prostate. The use of experimental models and a better knowledge of the female prostate gland in other species, can be useful to veterinary medicine as well as human medicine. Therefore the aim of this study is to check for the presence of this gland in female dogs of various breeds and age. For that purpose 25 urethras, from the bladder to the vulva, were collected, fixed in 10% neutral buffered formalin, routinely processed and sectioned into 4 slides of 4 µm, each with 40 µm gap between each set of 4 slides, using an automatic microtome and stained with Hematoxylin and Eosine (HE). The HE sections were evaluated for the presence of prostatic gland in the sample. Unstained tissue sections cut from paraffin blocks were marked with a polyclonal anti-PSA primary antibody. The prevalence of the gland was 32% (8/25). The structure of the paraurethral PSA-positive gland was acinar, organized in buds, with secretory epithelium varying from cubic to columnar; eccentric nuclei, with lose chromatin and a layer of basal cells, very similar to the male prostate were observed. In view of these characteristics, for the first time in the literature, was demonstrate that those glands. may be considered as female prostate in dogs, as they are in other vertebrates

Morphology of Richards' gland in the swarm-founding wasp (Hymenoptera, Vespidae)

Richards' gland is known for the majority of Epiponini wasps, and despite few experimental evidences, the taxonomic distribution in swarm-founder species and the function of this gland remain rather unclear. This work presents a morphological description of Richards' gland in Protonectarina sylveirae. The gland is formed by a cluster of class 3 cells underneath the anterior margin of the fifth metasomal sternite, and a reservoir formed by the intersegmental membrane between the fourth and fifth metasomal sternites where the secretion can be stored. The secretory cells contain a branched end apparatus that carries the secretory products towards the duct cell. Externally, the cuticle of the sternite, where the duct cells penetrate, is characterized by modifications as scales with very numerous pores. The presence of Richards' gland according to the model proposed by Samacá et al. 2013 in Protonectarina corroborates the single origin of this gland in Epiponini. The occurrence of a Golgi apparatus and smooth endoplasmic reticulum suggests pheromone production.

Antidepressant treatment decreases daily salt intake and prevents heart dysfunction following subchronic aortic regurgitation in rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Thermoregulatory consequences of salt loading in the lizard Pogona vitticeps

Previous research has demonstrated that dehydration increases the threshold temperature for panting and decreases the thermal preference of lizards. Conversely, it is unknown whether thermoregulatory responses such as shuttling and gaping are similarly influenced. Shuttling, as an active behavioural response, is considered one of the most effective thermoregulatory behaviours, whereas gaping has been proposed to be involved in preventing brain over-heating in lizards. In this study we examined the effect of salt loading, a proxy for increased plasma osmolality, on shuttling and gaping in Pogona vitticeps. Then, we determined the upper and lower escape ambient temperatures (UETa and LETa), the percentage of time spent gaping, the metabolic rate ((V) over dot(O2)), the evaporative water loss (EWL) during gaping and non-gaping intervals and the evaporative effectiveness (EWL/(V) over dot(O2)) of gaping. All experiments were performed under isotonic (154 mmol l(-1)) and hypertonic saline injections (625, 1250 or 2500 mmol l(-1)). Only the highest concentration of hypertonic saline altered the UETa and LETa, but this effect appeared to be the result of diminishing the animal's propensity to move, instead of any direct reduction in thermoregulatory set-points. Nevertheless, the percentage of time spent gaping was proportionally reduced according to the saline concentration; (V) over dot(O2) was also decreased after salt loading. Thermographic images revealed lower head than body surface temperatures during gaping; however this difference was inhibited after salt loading. Our data suggest that EWL/(V) over dot(O2) is raised during gaping, possibly contributing to an increase in heat transfer away from the lizard, and playing a role in head or brain cooling.

Effect of temperature on salt-salt aqueous biphasic systems: manifestations of upper critical solution temperature

Water-miscible ionic liquids (ILs) may be salted out using kosmotropic salts such as potassium phosphate (K3PO4) to form salt-salt aqueous biphasic systems (ABS). The effect of temperature on these systems has been studied using phase diagrams and it is observed that the degree of binodal shift decreases (requiring lower IL and kosmotropic salt concentrations) with the increase of temperature following the trend [C(4)mim]Cl > [C(4)py]Cl > [C(4)mmim] Cl > [N-4444]Cl. This trend can be correlated with the decreasing hydrogen bonding abilities of each salt. The phase behavior was also interpreted on the basis of critical solution temperature behavior of pure aqueous ionic liquid solutions. Additionally, the distribution of alcohols in these systems was studied as a function of temperature and it was found that the distribution ratios did not change with changes in temperature. The Gibbs energy of transfer of a methylene group in these systems and correlation to tie-line length was also determined. It was concluded that while the miscibility of alcohols increases in the ILs with increasing temperature, phase divergence in the aqueous biphasic system decreases, and thus these competing forces tend to cancel each other out for small polar molecules. A comparison is provided for the response to temperature in the currently studied salt-salt systems and analogous ABS formed by the addition of hydrophilic polymers to kosmotropic salts (polymer-salt) or other polymers (polymer-polymer).

A simple high-performance liquid chromatography assay for on-line determination of catecholamines in adrenal gland by direct injection on an ISRP column

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Genistein reduces the noxious effects of in utero bisphenol A exposure on the rat prostate gland at weaning and in adulthood

Bisphenol A (BPA) is one hormonally active chemical with potential deleterious effects on reproductive organs, including breast and prostate. In contrast, genistein (GEN) is the major phytoestrogen of soy that presents potential protective effects against hormone-dependent cancers, including that of the prostate. Thus, pregnant Sprague-Dawley rats were treated with BPA at 25 or 250 μg/kg/day by gavage from gestational day (GD) 10-21 with or without dietary GEN at 250 mg/kg/chow (∼5.5 mg/kg/day). Then, male offspring from different litters were euthanized on post-natal day (PND) 21 and 180. At PND21, BPA 25 exposure induced early prostatic changes while dietary GEN attenuated some deleterious actions this xenoestrogen on epithelial cell proliferation levels, androgen receptor expression and prostatic architecture in male offspring. At PND180, a significant increase in incidence of prostatic multifocal inflammation/reactive hyperplasia and atypical hyperplasia were observed in male offspring from dams that received BPA 25. On the other hand, maternal GEN feeding attenuated some the adverse effects of BPA 25 on prostate disease at late-in-life. This way, the present findings point to preventive action of dietary GEN on deleterious effects of gestational BPA exposure in both early and late prostate development in offspring F1.

Evaluation of prognostic factors and survival rates in malignant feline mammary gland neoplasms

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Community Structure and Seasonal Dynamics of Dactylogyrus spp. (Monogenea) on the Fathead Minnow (Pimephales promelas) from the Salt Valley Watershed, Lancaster County, Nebraska

The gill monogene communities of Pimephales promelas (fathead minnow) in three distinct sites on converging streams were investigated from 2004 to 2006 in three different seasons. Thirty collections of P. promelas were made in southeastern Nebraska along three converging tributaries: Elk Creek (40.88534°N, 96.83366°W), West Oak Creek (40.9082°N, 96.81432°W), and Oak Creek (40.91402°N, 96.770583°W), Lancaster County, Nebraska. In all, 103 P. promelas were collected from Elk Creek, 115 from West Oak Creek, and 78 from Oak Creek and examined for gill monogenes. Among the P. promelas collected, 93.5% were infected with up to three species of Dactylogyrus, including Dactylogyrus simplex Mizelle, 1937, Dactylogyrus bychowskyi Mizelle, 1937, and Dactylogyrus pectenatus Mayes, 1977. Mean intensities at Elk Creek, West Oak Creek, and Oak Creek were 17.6, 22.8, and 25.1, and prevalences 88, 95, and 97%, respectively. At these three sites: (1) P. promelas does not share Dactylogyrus species with Semotilus atromaculatus (creek chub) or Notropis stramineus (sand shiner); (2) fish size and sex are not predictive of Dactylogyrus infection; (3) Dactylogyrus spp. vary (not always predictably) in their seasonal occurrence; (4) populations of Dactylogyrus spp. respond to environmental differences among sites; and (5) the community structure of Dactylogyrus spp. (order of abundance) is independent of environment.

Community structure and dynamics of Monogenea and Trematoda in three North American cyprinid species in the Salt Valley Watershed, Nebraska.

An investigation was made of the communities of gill monogene genus Dactylogyrus (Platyhelminthes, Monogenea) and the populations of blackspot parasite (Platyhelminthes, Trematoda) of Pimephales promelas, Notropis stramineus, and Semotilus atromaculatus in 3 distinct sites along the 3 converging tributaries in southeastern Nebraska from 2004 to 2006. This work constitutes the first multi-site, multi-year study of a complex community of Dactylogyrus spp. and their reproductive activities on native North American cyprinid species. The biological hypothesis that closely related species with direct lifecycles respond differently to shared environmental conditions was tested. It was revealed that in this system that, Cyprinid species do not share Dactylogyrus species, host size and sex are not predictive of infection, and Dactylogyrus community structure is stable, despite variation in seasonal occurrence and populations among sites. The biological hypothesis that closely related species have innate differences in reproductive activities that provide structure to their populations and influence their roles in the parasite community was tested. It was revealed that in this system, host size, sex, and collection site are not predictive of reproductive activities, that egg production is not always continuous and varies in duration among congeners, and that recruitment of larval Dactylogyrus is not continuous across parasites’ reproductive periods. Hatch timing and host availability, not reproductive timing, are the critical factors determining population dynamics of the gill monogenes in time and space. Lastly, the biological hypothesis that innate blackspot biology is responsible for parasite host-specificity, host recruitment strategies and parasite population structure was tested. Field collections revealed that for blackspot, host size, sex, and collection month and year are not predictive of infection, that parasite cysts survive winter, and that host movement is restricted among the 3 collection sites. Finally, experimental infections of hosts with cercaria isolated from 1st intermediate snail hosts reveal that cercarial biology, not environmental circumstances, are responsible for differences in infection among hosts.

Virus-Associated Tumours of the Harderian Gland in Laboratory-Reared Voles, Clethrionomys rutilis (Pallas)

Tumors of the Harderian gland occurred frequently in red-backed voles, Clethrionomys rutilus (Pallas), in a captive colony maintained since 1957. Although the tumors became obvious only in animals about a year old and older, early stage changes were histologically evident in glands from younger, clinically normal voles. The tumors ranged in type from poorly differentiated adenoma to adenocarcinoma, with invasion of adjacent tissues and characteristic deformation of the zygomata. Electron micrographs disclosed viral particles in the cytoplasm of glands from clinically normal animals as well as in glands showing malignant changes. The tumor was not observed in arvicoline rodents of other species maintained in the same rooms with the red-backed voles.

Digestive peptidases and proteinases in the midgut gland of the pink shrimp Farfantepenaeus paulensis (Crustacea, Decapoda, Penaeidae)

Proteases from the midgut gland of the Farfantepenaeus paulensis juveniles were assessed. Enzyme activity was determined using protease substrates and inhibitors. The effect of pH, temperature and calcium on proteolytic activity was assayed. Caseinolytic activity was analysed in substrate-sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Trypsin, chymotrypsin and leucine aminopeptidase activity was detected. Proteolytic activity was strongly inhibited by the specific trypsin inhibitors. Tosyl-phenylalanine chloromethyl ketone inhibited 59.3% of chymotrypsin activity. The greatest trypsin-like activity occurred at pH 8.0 and 45 degrees C. Chymotrypsin-like activity reached maximal values at alkaline pH (7.2-9.0) and 55 degrees C. CaCl(2) did not increase trypsin-like activity, but rather inhibited it at concentrations of 30 (20%), 50 (30%) and 100 mM (50%). The substrate-SDS-PAGE zymogram revealed eight proteinase bands. Two possibly thermal-resistant (85 degrees C, 30 min) chymotrypsin isoforms were found, which were inhibited by phenyl-methyl-sulphonyl-fluoride. Aminopeptidase activity of enzyme extracts (Arg, Leu, Lys, Phe and Val) and the recommended concentrations of these essential amino acids in penaeid shrimp diets were positively correlated (P < 0.05). Beause protein digestion involves the combined action of different enzymes, adequate knowledge of shrimp digestion and enzyme characteristics is required for the assessment of the digestive potential of different feed sources and development of in vitro digestibility protocols.

Consumer attitudes, knowledge, and behavior related to salt consumption in sentinel countries of the Americas

Objective. To describe individual attitudes, knowledge, and behavior regarding salt intake, its dietary sources, and current food-labeling practices related to salt and sodium in five sentinel countries of the Americas. Methods. A convenience sample of 1 992 adults (>= 18 years old) from Argentina, Canada, Chile, Costa Rica, and Ecuador (approximately 400 from each country) was obtained between September 2010 and February 2011. Data collection was conducted in shopping malls or major commercial areas using a questionnaire containing 33 questions. Descriptive estimates are presented for the total sample and stratified by country and sociodemographic characteristics of the studied population. Results. Almost 90% of participants associated excess intake of salt with the occurrence of adverse health conditions, more than 60% indicated they were trying to reduce their current intake of salt, and more than 30% believed reducing dietary salt to be of high importance. Only 26% of participants claimed to know the existence of a recommended maximum value of salt or sodium intake and 47% of them stated they knew the content of salt in food items. More than 80% of participants said that they would like food labeling to indicate high, medium, and low levels of salt or sodium and would like to see a clear warning label on packages of foods high in salt. Conclusions. Additional effort is required to increase consumers' knowledge about the existence of a maximum limit for intake and to improve their capacity to accurately monitor and reduce their personal salt consumption.

Lufaxin, a Novel Factor Xa Inhibitor From the Salivary Gland of the Sand Fly Lutzomyia longipalpis Blocks Protease-Activated Receptor 2 Activation and Inhibits Inflammation and Thrombosis In Vivo

Objective-Blood-sucking arthropods' salivary glands contain a remarkable diversity of antihemostatics. The aim of the present study was to identify the unique salivary anticoagulant of the sand fly Lutzomyia longipalpis, which remained elusive for decades. Methods and Results-Several L. longipalpis salivary proteins were expressed in human embryonic kidney 293 cells and screened for inhibition of blood coagulation. A novel 32.4-kDa molecule, named Lufaxin, was identified as a slow, tight, noncompetitive, and reversible inhibitor of factor Xa (FXa). Notably, Lufaxin's primary sequence does not share similarity to any physiological or salivary inhibitors of coagulation reported to date. Lufaxin is specific for FXa and does not interact with FX, Dansyl-Glu-Gly-Arg-FXa, or 15 other enzymes. In addition, Lufaxin blocks prothrombinase and increases both prothrombin time and activated partial thromboplastin time. Surface plasmon resonance experiments revealed that FXa binds Lufaxin with an equilibrium constant approximate to 3 nM, and isothermal titration calorimetry determined a stoichiometry of 1:1. Lufaxin also prevents protease-activated receptor 2 activation by FXa in the MDA-MB-231 cell line and abrogates edema formation triggered by injection of FXa in the paw of mice. Moreover, Lufaxin prevents FeCl3-induced carotid artery thrombus formation and prolongs activated partial thromboplastin time ex vivo, implying that it works as an anticoagulant in vivo. Finally, salivary gland of sand flies was found to inhibit FXa and to interact with the enzyme. Conclusion-Lufaxin belongs to a novel family of slow-tight FXa inhibitors, which display antithrombotic and anti-inflammatory activities. It is a useful tool to understand FXa structural features and its role in prohemostatic and proinflammatory events. (Arterioscler Thromb Vasc Biol. 2012;32:2185-2196.)