Epidemiological aspects of lice (Menacanthus species) infections in laying hen flocks from the State of Minas Gerais, Brazil.

The epidemiology of chicken lice species such as Menacanthus stramineus, M. cornutus and M. pallidulus were studied during an observational, analytical and sectional survey, to determine predisposing factors for their occurrence in laying hen farms in the State of Minas Gerais, Brazil. A total of 431 houses on 43 farms were visited in 2012. M. cornutus, M. stramineus and M. pallidulus occurred in 20.9%, 11.6% and 11.6% of farms, respectively. The frequencies of occurrence of M. cornutus, M. stramineus and M.pallidulus in poultry houses were 10.4%, 8.8% and 3.7%, respectively. The epidemiological determinants for the occurrence of these species were investigated using Poisson or logistic regression models. The region of the farm, the recent use of acaricides and the presence of birds, such as saffron finch (Sicalis flaveola), feral pigeon (Columba livia) and Guira cuckoo (Guira guira) around the farms were related to the epidemiology of M. cornutus. Infestation by M. stramineus was associated with age of birds, number of birds per cage and the presence of Guira cuckoo and Chopi blackbird (Gnorimopsar chopi) near the poultry houses. The occurrence of M. pallidulus was influenced by the type of facilities, presence of cattle egret (Bubulcus ibis) and free-range domestic hens around the farm. The use of wire mesh nets in the houses and of forced moulting did not influence lice infestation.

Morphological effects of neem (Azadirachta indica A. Juss) seed oil with known azadirachtin concentrations on the oocytes of semi-engorged Rhipicephalus sanguineus ticks (Acari: Ixodidae).

The concern about the harmful effects caused by synthetic pesticides has led to the search for safe and ecological alternatives for pest control. In this context, the neem tree (Azadirachta indica) stands out due to its repellent properties and effects on various arthropods, including ticks. For this reason, this study aimed to demonstrate the potential of neem as a control method for Rhipicephalus sanguineus ticks, important vectors of diseases in the veterinary point of view. For this, R. sanguineus semi-engorged females were subjected to treatment with neem seed oil enriched with azadirachtin, its main compound, and ovaries were assessed by means of morphological techniques in conventional light microscopy, confocal laser scanning microscopy, and transmission electron microscopy. Neem demonstrated a clear dose-dependent effect in the analyzed samples. The observed oocytes presented, especially in the groups treated with higher concentrations of neem oil, obvious signs of cytoplasmic disorganization, cellular vacuolization, nuclear and nucleolar irregularity, dilation in mitochondrial cristae, alterations in mitochondrial matrix, and swelling of rough endoplasmic reticulum. Intracellular microorganisms were observed in all analyzed groups, reinforcing the importance of ticks in the transmission of pathogens. A greater quantity of microorganisms was noted as the concentration of neem increased, indicating that the damaged oocytes may be more susceptible for their development. Such morphological alterations may promote future damages in reproductive performance of these animals and demonstrate the potential of neem seed oil for the control of R. sanguineus ticks, paving the way for new, cheaper, and safer methods of control.

A suite of microsatellite markers for genetic management of captive cracids (Aves, Galliformes).

Cracids are medium to large frugivorous birds that are endemic to the Neotropics. Because of deforestation and overhunting, many species are threatened. The conservation of several species has relied on captive breeding and reintroduction in the wild, but captive populations may be inbred. Microsatellite tools can permit the construction of genetic pedigrees to reduce inbreeding, but only a few loci are available for this group of birds. Here, we present 10 novel polymorphic microsatellite loci and the cross-amplification of these and of 10 additional loci available in the literature in a panel of 5 cracid species, including 3 species with high conservation concern. We provide the first polymorphic loci for the jacutinga, Aburria jacutinga (N = 8), and red-billed curassow, Crax blumenbachii (N = 9), and additional loci for bare-faced curassow, C. fasciolata (N = 8), Alagoas curassow, Pauxi mitu (N = 5), and razor-billed curassow, P. tuberosa (N = 5). The average number of alleles was 2.9 for A. jacutinga, 2.7 for C. blumenbachii, 3.5 for C. fasciolata, 2.6 for P. mitu, and 5.7 for P. tuberosa. The mean expected heterozygosities were 0.42, 0.40, 0.48, 0.37, and 0.59, respectively. The average probabilities that the set of loci would not exclude a pair of parents of an arbitrary offspring were 2.9% in A. jacutinga, 1% in C. blumenbachii, 0.5% in C. fasciolata, 0.4% in P. mitu, and 0.002% in P. tuberosa suggesting that these loci may be adequate for parentage analysis and to implement ex situ genetic management plans.

Yield and centesimal characterization of collagen extracted from the skin of peacock bass Cichla monoculus.

Fish processing provides waste of around 50.0% to 70.0% of the animal's initial weight, especially the skin. Thus, this residue contains the by-product that allows biopolymers to be obtained, highlighting collagen, which can be widely used in different areas. The present study aimed to evaluate the yield of collagen extracted from peacock bass Cichla monoculus skin and to characterize them physicochemically. Twenty-five peacock bass with an average weight of 646 ± 175 g were used. The skin samples were removed by manual filleting and weighed, with an average yield of 3.7%. Subsequently, such models were analyzed for chemical composition, showing 61.8% for moisture, 29.3% for crude protein, 1.5% for ash, 6.3% for total lipids, and 1.2% for non-nitrogenous extract (NNE). Acid-soluble collagen (ASC) presented an average yield of 8.2%, presenting in its analysis of centesimal composition 12.5% ​​of moisture, 82.6% of crude protein, 1.1% of ash, 2.6% of total lipids, and 1.2% NNE. The skin and collagen extracted from the tucunaré skin have technological potential for use in the preparation of products, adding value to these by-products from fish processing.

Increased bioavailability of primaquine using poly(ethylene oxide) matrix extended-release tablets administered to beagle dogs.

Primaquine (PQ) is used for the radical cure of Plasmodium vivax malaria and can cause serious side effects in some individuals. The development of an extended-release dosage with poly(ethylene oxide) as a hydrophilic polymer has been investigated to improve drug efficacy and tolerability. The aim of this study was to evaluate in vivo a new extended-release formulation of PQ (60 mg). The formulation was administered to beagle dogs and plasma PQ concentrations were compared to a conventional immediate-release formulation of PQ (60 mg). The evaluation was carried out using a validated high-performance liquid chromatography method using solid-phase extraction. Total PQ exposure in beagle dogs was 2.2 times higher (area under curve of 12 193 versus 5678 ng h/ml) and the elimination half-life of PQ was a 19-fold greater (12.95 hours versus 0.68 hours) with the extended-release tablets compared with the immediate-release tablets. These findings suggest that the extended-release formulation of PQ merits further evaluation for the treatment of P. vivax malaria and/or chemoprophylaxis.

Efficacy of carvacrol on Rhipicephalus (Boophilus) microplus engorged female ticks (Canestrini, 1887) (Acari: Ixodidae): effects on mortality and reproduction.

The activity of carvacrol was evaluated in R. microplus female ticks by estimating the mean lethal concentration (LC50) and the acaricidal efficacy. Ticks were subjected to the Adult Immersion Test (AIT) to calculate LC50. From this value, the AIT was performed again at the concentrations of 20%, 40%, 60%, 80% and 100% of the LC50. Two control groups were established: one treated with distilled water and one with the solvent (ethanol 50%). The following parameters were evaluated: female weight before oviposition, egg mass weight, pre-oviposition and incubation period, hatching percentage, egg production index, fecundity rate, estimated reproduction, reduction in oviposition and hatching, and product efficacy. The obtained LC50 was 20.11 mg/mL. Egg mass weight, egg production index, pre-oviposition and fecundity rates of groups treated with 80% and 100% of LC50 were statistically different when compared to control groups. The product efficacy in groups treated with 100% of LC50 was 61.10%.

Angiotensin II-mediated vasodilation is reduced in adult spontaneously hypertensive rats despite enhanced expression of AT2 receptors.

1. The vasodilator action of angiotensin (Ang) II has not yet been demonstrated in spontaneously hypertensive rats (SHR), nor have any possible changes in this response during the development of hypertension. 2. In the present study, the vasodilator effect of AngII was evaluated in the rat isolated, preconstricted mesenteric arterial bed (MAB) from 6- (young) and 24-week-old (adult) SHR and compared with effects on MAB from age-matched normotensive rats (control). 3. Angiotensin II (10-300 nmol) induced vasodilation in noradrenaline (NA)-preconstricted MAB that was greater in vessels from young compared with adult rats in both the control and SHR groups. Angiotensin II-induced vasodilation was reduced by the angiotensin AT(2) receptor antagonist PD 123319 (10 micromol/L), the angiotensin-(1-7) receptor antagonist A779 (1 micromol/L) and the bradykinin B(2) receptor antagonist HOE-140 (0.01 micromol/L), but not by the AT(1) receptor antagonist losartan (30 micromol/L). Expression of AT(2) receptors was weak in vessels from adult control rats compared with that in young control rats, whereas in young SHR AT(2) receptor expression was increased compared with that in young control rats. This increased expression of AT(2) receptors was maintained in adult SHR and there was no significant difference in AT(2) receptor expression between young and old SHR. 4. The findings of the present suggest that AngII induces an AT(2) receptor-mediated vasodilator effect in the MAB via activation of angiotensin-(1-7) and bradykinin receptors, an action that is reduced in adult control rats and adult SHR. In adult control rats, the attenuated response of AngII is probably due to endothelial dysfunction and reduced expression of AT(2) receptors, whereas in adult SHR it is associated with endothelial dysfunction alone. Increased expression of AT(2) receptors in SHR may represent a counteracting response for modulating blood pressure.

Morphological alterations in salivary glands of Rhipicephalus sanguineus ticks (Acari: Ixodidae) exposed to neem seed oil with known azadirachtin concentration.

Neem (Azadirachta indica) has attracted the attention of researchers worldwide due to its repellent properties and recognized effects on the morphology and physiology of arthropods, including ticks. Therefore, this study aimed to demonstrate the effects of neem seed oil enriched with azadirachtin on salivary glands of Rhipicephalus sanguineus ticks, targets of great veterinary interest because of their ability to transmit pathogens to dogs. For this, R. sanguineus semi-engorged females were subjected to treatment with neem seed oil, with known azadirachtin concentrations (200, 400 and 600ppm). After dissection, salivary glands were collected and evaluated through morphological techniques in light microscopy, confocal scanning laser microscopy and transmission electron microscopy, so that the possible relation between neem action and further impairment in these ectoparasites feed performance could be established. Neem oil demonstrated a clear dose-dependent effect in the analyzed samples. The agranular (type I) and granular acini (types II and III) showed, particularly in individuals treated with the highest concentrations of the product, cells with irregular shape, intense cytoplasmic disorganization and vacuolation, dilation of rough endoplasmic reticulum lumen, besides alterations in mitochondrial intermembrane space. These morphological damages may indicate modifications in salivary glands physiology, demonstrating the harmful effects of compounds present in neem oil on ticks. These results reinforce the potential of neem as an alternative method for controlling R. sanguineus ticks, instead of synthetic acaricides.

Populational dynamics of Stomoxys calcitrans (Linneaus) (Diptera: Muscidae) in three biocenosis, Minas Gerais, Brazil.

Populational flux of the adult phase of Stomoxys calcitrans was observed in the municipal district of Pedro Leopoldo, Minas Gerais, Brazil. Three biocenoses were selected for the study: stable agrobiocenosis, pastural agrobiocenosis and eubiocenosis. The occurrence and the populational flux of the insects, using the Magoon trap for their capture, were established. For each trap located in different biocenoses, a crossbred calf (Bos taurusxBos indicus) approximately 6-month-old was used as "live bait," exposed weekly for 48h in the traps. Of the three agrobiocenoses studied, the stable agrobiocenosis contributed the greatest number of specimens of. S. calcitrans captured, corresponding to 96.9% of the total flies of this species collected. S. calcitrans shows seasonal behavior for approximately 6 months (spring and summer being the rainiest months of the year). The population peaked during the months of November and December. During the months of July and August, there was no capture of flies.

Monosomy 22 and del(10)(p12) in an ameloblastoma previously diagnosed as an adenoid cystic carcinoma of the salivary gland.

Short-term cultures of a collagenase disaggregated ameloblastoma previously diagnosed as an adenoid cystic carcinoma of the salivary gland were shown by cytogenetic analysis to have the clonal karyotype 45,XY,del(10)(p12),-22. The data may indicate that the loss of genes of chromosome 22, as well as of 10p, could be a critical event in the evolutionary pattern of odontogenic neoplasias.

Anticonvulsant and proconvulsant roles of nitric oxide in experimental epilepsy models.

The effect of acute (120 mg/kg) and chronic (25 mg/kg, twice a day, for 4 days) intraperitonial injection of the nitric oxide (NO) synthase (NOS) inhibitor NG-nitro-L-arginine (L-NOARG) was evaluated on seizure induction by drugs such as pilocarpine and pentylenetetrazole (PTZ) and by sound stimulation of audiogenic seizure-resistant (R) and audiogenic seizure-susceptible (S) rats. Seizures were elicited by a subconvulsant dose of pilocarpine (100 mg/kg) only after NOS inhibition. NOS inhibition also simultaneously potentiated the severity of PTZ-induced limbic seizures (60 mg/kg) and protected against PTZ-induced tonic seizures (80 mg/kg). The audiogenic seizure susceptibility of S or R rats did not change after similar treatments. In conclusion, proconvulsant effects of NOS inhibition are suggested to occur in the pilocarpine model and in the limbic components of PTZ-induced seizures, while an anticonvulsant role is suggested for the tonic seizures induced by higher doses of PTZ, revealing inhibitor-specific interactions with convulsant dose and also confirming the hypothesis that the effects of NOS inhibitors vary with the model of seizure.

Seasonal dynamics of Anocentor nitens on horses in Brazil.

Anocentor nitens is a widespread ectoparasite of horses in Brazil. A study of the seasonal dynamics of the parasitic phase of this tick was made by regular census of engorging females (>/=4mm) on free-ranging horses, fortnightly from July 1995 to July 1997, at Pedro Leopoldo, Minas Gerais. Twenty horses were divided into four groups of five animals per group, each having a similar mix of resistant and less resistant animals, based on initial infestation. Every 2 weeks, one of the groups, in sequence, was treated with an acaricide to prevent excessive infestations, and female ticks were censused 38 days later. The acaricide dips did not interfere with the seasonal dynamics of the tick population, which produced three major peaks of activity over a 12-month period. The first two peaks were in the hot, wet season and the third in the cold dry season. Tick numbers were similar for the two 12-month periods, decreasing from the spring and summer to the autumn and winter. Infestation rates were not equal among different horses. Twenty percent of the horses were responsible for 48% of the total parasite load, while 30% accounted for only 2.5% of the total parasite load. Principal predilection sites were; the ear (61%), mane (21%), and muzzle and face (6%). Measures for the strategic control of A. nitens ticks are discussed.

Seasonal dynamics of the free-living phase of Anocentor nitens at Pedro Leopoldo, Minas Gerais, Brazil.

An understanding of seasonal dynamics in the free-living phase of the tropical horse tick, Anocentor nitens, is vital for effective control measures. This study examines seasonal changes in the oviposition and incubation periods, eclosion rates, reproductive success, and larval survival in the free-living phase during the period June 1995-July 1997. Ten engorged female ticks, placed individually in wire-gauze tubes, were exposed in a field of Brachiaria decumbens fortnightly each month, and monitored to measure the duration of the various reproductive parameters, and success. Larval abundance was estimated indirectly, through the percentage of females with viable progeny, and directly by using a flagging method. Duration of the free-living cycle ranged from 12.3 weeks (October and December) to 23.5 weeks (March). The cycle was prolonged in cold and dry months. Larval survival was longer from February to July, and reduced from August to February. Oviposition was recorded in all months, and the egg production index ranged from 26.7 to 47.1%. The eclosion rate ranged from 0.1 to 76.6% in different months. Monthly estimates of larval abundance in the pasture were similar for the two methods used, being higher in months with higher temperatures, relative humidity and rainfall.

Population dynamics of the free-living stages of Amblyomma cajennense (Fabricius, 1787) (Acari: ixodidae) on pastures of Pedro Leopoldo, Minas Gerais State, Brazil.

A study on the population behavior of Amblyomma cajennense larvae, nymphs and adult free-living stages was carried out in Pedro Leopoldo County, Minas Gerais State, Brazil, from July 1995 to July 1997. Larvae were collected from pasture from April to October using the technique of drag sampling with flannelette. The maximal larval population was observed during autumn (May) representing, respectively, 48 and 82% of the total numbers recovered during the first and the second years of the experiment. Nymphs and adults were captured throughout the year by the use of traps with carbon dioxide as chemical attractant. The highest population of nymphs occurred during the winter (July), representing 39.5% of the total collected specimens. Adults had the highest population density on pasture during spring and summer, i.e., from August to May, with peaks in January and February, representing 46 and 38.3% of the total collected specimens during the first and the second year of study, respectively.

Horse resistance to natural infestations of Anocentor nitens and Amblyomma cajennense (Acari: Ixodidae).

The objective of this study was to investigate some aspects of horse resistance to natural infestations of Anocentor nitens and Amblyomma cajennense over a 2-year period. Free-living stages of A. nitens were used to evaluate the influence of season of the year on horse resistance. Every 2 weeks, 10 selected engorged females, weighing 150-329 mg, were removed from naturally infested horses and were individually placed into glass tubes closed with a cotton stopper, and maintained in an incubator. The biological parameters evaluated varied according to the season of the year, i.e., reproductive efficiency, maximum larval survival (MLS) and egg-hatching rates were significantly lower in spring/summer than in fall/winter. At 14-day intervals, females of A. nitens and A. cajennense were counted on each side of the body of five mares. A comparison between the animal with the lowest infestation and the animal with the highest infestation showed greater differences in animals infested with A. nitens than those infested with A. cajennense. Ten animals were found to carry 64.9% of the total parasite burden of A. cajennense and 88.6% of the highest infestations of A. nitens females. A seasonal variation on intensity of horse resistance to A. nitens was observed during the study. However, this was not observed for A. cajennense. Cross-resistance was observed in animals with the highest total number of A. cajennense and the highest number of A. cajennense adults (r=0.817), larvae (r=0.756), and A. nitens females (r=0.799). These results led to the conclusion that changes in horse resistance to A. nitens occur seasonally. As far as the total population of A. cajennense and the female stage of A. nitens are concerned, horses develop cross-resistance.

Occurrence of coligranulomatosis in coturnix quail in Uberlândia, Minas Gerais, Brazil.

The occurrence of coligranulomatosis in a Brazilian flock of 1500 8-to-12-month-old coturnix quail is described. The disease caused an 85% drop in egg production and 15% mortality. Lesions were located on the mesentery, intestines, gizzard, heart, oviducts, ovaries, and liver. Samples of these organs were submitted for bacteriological culture, isolation, identification, pathogenicity assay by inoculation of diluted cultures into healthy hens, and histopathology.

[Preservation of hearts by perfusion under pressure]. / Técnica de preservação de corações através de perfusão sob pressão.

PURPOSE: Development of method used to fix hearts in a reduced time, with preservation of their structures and characteristics. METHODS: Fifty normal human hearts were fixed in a system with four reservoirs, a roller pump, PVC tubes and a plastic recipient. This system was used to maintain the continuous injection by pressure of formaldehyde solution, to the interior of the heart. RESULTS: The fixation was satisfactory, pré-fixation time (13.93 +/- 5.13 min) and fixation time (60.53 +/- 12.50 min) were reduced related to previously utilized methods. CONCLUSION: The method was good, with decrease of fixation time and obtention of fixed hearts, with preservation of their structures and characteristics.

Detection of parasite antigens in Leishmania infantum-infected spleen tissue by monoclonal antibody-, piezoelectric-based immunosensors.

Diseases such as leishmaniases are important causes of morbidity and mortality in Brazil, and their diagnoses need to be improved. The use of monoclonal antibodies has ensured high specificity to immunodiagnosis. The development of an immunosensor, coupling a monoclonal antibody to a bioelectronic device capable of quickly detecting Leishmania sp. antigens both qualitatively and quantitatively, is a promising alternative for the diagnosis of leishmaniasis due to its high specificity, low cost, and portability, compared with conventional methods. The present work was aimed at developing an immunosensor-based assay for detecting Leishmania infantum antigens in tissues of infected hosts. Four hybridomas producing monoclonal antibodies against L. infantum had their specificity confirmed by enzyme-linked immunosorbent assay. These antibodies were immobilized on a gold surface, covered with a thin film of 2-aminoethanethiol (cysteamine) and glutaraldehyde, blocked with glycine, and placed into contact with extracts of L. infantum -infected and noninfected control hamster spleens. The assay was able to detect 1.8 × 10(4) amastigotes/g of infected tissue. These results demonstrated that this assay may be useful for quantifying L. infantum amastigotes in organs of experimental animals for studies on pathogenesis and immunity and that it is a promising tool for the development of a diagnostic method, based on antigen detection, of human and dog visceral leishmaniasis.

[Microbiology of diabetic foot infections: role of ertapenem]. / Microbiologia das infecções no pé diabético: o papel do ertapenem.

Many patients with diabetes develop foot ulcers that are very susceptible to infections which may place the patients at risk for lower-limb amputation. Such infections require adequate management with antibiotics. The authors performed a systematic analysis and critical review of studies with the dual aim of assessing bacterial profiles and antimicrobial susceptibility patterns in patients with diabetic foot infections using various methods for sample collection and evaluating the safety and efficacy of ertapenem as initial empirical treatment for such infections. Following a selection of only studies with adequate description of methods for pathogen isolation and antibiogram determination, nine studies were included. The need for adequate prospective multicenter studies to assess the value of empirical antibiotic regimens for diabetic foot became evident and the conclusions were as follows: proper identification of causative agents, appropriate antibiotic therapy and management of complications in these infections are essential to achieve a successful outcome; the sampling procedure is extremely important in the evaluation of the microbial flora of the foot ulcer; susceptibility testing should be performed routinely at least for those species with unpredictable resistance; and ertapenem has been shown to be useful in the treatment of a wide range of moderate-to-severe lower extremity infections in a broad spectrum of patients.

Machine learning techniques and drug design.

The interest in the application of machine learning techniques (MLT) as drug design tools is growing in the last decades. The reason for this is related to the fact that the drug design is very complex and requires the use of hybrid techniques. A brief review of some MLT such as self-organizing maps, multilayer perceptron, bayesian neural networks, counter-propagation neural network and support vector machines is described in this paper. A comparison between the performance of the described methods and some classical statistical methods (such as partial least squares and multiple linear regression) shows that MLT have significant advantages. Nowadays, the number of studies in medicinal chemistry that employ these techniques has considerably increased, in particular the use of support vector machines. The state of the art and the future trends of MLT applications encompass the use of these techniques to construct more reliable QSAR models. The models obtained from MLT can be used in virtual screening studies as well as filters to develop/discovery new chemicals. An important challenge in the drug design field is the prediction of pharmacokinetic and toxicity properties, which can avoid failures in the clinical phases. Therefore, this review provides a critical point of view on the main MLT and shows their potential ability as a valuable tool in drug design.