New approach for reproductive toxicity assessment: chromatoid bodies as a target for methylmercury and polychlorinated biphenyls in prepubertal male rats

This study investigated the reproductive toxicity of methylmercury (MeHg) and Aroclor (Sigma-Aldrich), alone or in combination, following exposure of prepubertal male rats considering the chromatoid body (CB) as a potential target. The CB is an important molecular regulator of mammalian spermatogenesis, primarily during spermatid cytodifferentiation. Male Wistar rats were exposed to MeHg and/or Aroclor , according the following experimental design: control group, which was administered in corn oil (vehicle) only; MeHg-treated group, which was administered 0.5mg kg-1 day-1 MeHg; Aroclor-treated group, which was administered 1mg kg-1 day-1 Aroclor; Mix-LD, group which was administered a low-dose mixture of MeHg (0.05mg kg-1 day-1) and Aroclor (0.1mg kg-1 day-1); and Mix-HD group, which was administered a high-dose mixture of MeHg (0.5mg kg-1 day-1) and Aroclor (1.0mg kg-1 day-1). MeHg was diluted in distilled water and Aroclor was made up in corn oil (volume 1mL kg-1). Rats were administered the different treatments from PND23 to PND53 by gavage, . The morphophysiology of CBs was analysed, together with aspects of steroid hormones status and regulation, just after the last treatment on PND53. In addition, the long-term effects on sperm parameters were assessed in adult animals. MeHg exposure increased mouse VASA homologue (MVH) protein levels in seminiferous tubules, possibly affecting the epigenetic status of germ cells. Aroclor produced morphological changes to CB assembly, which may explain the observed morphological defects to the sperm flagellum and the consequent decrease in sperm motility. There were no clear additive or synergistic effects between MeHg and Aroclor when administered in combination. In conclusion, this study demonstrates that MeHg and Aroclor have independent deleterious effects on the developing testis, causing molecular and morphological changes in CBs. To the best of our knowledge, this is the first study to show that CBs are targets for toxic agents.

Influence of the host diet on the performance of Doryctobracon areolatus (Hymenoptera: Braconidae)

Fitness in parasitoids is generally influenced by host quality. We evaluated the development parameters of Doryctobracon areolatus (Hymenoptera: Braconidae) parasitoid on Anastrepha fraterculus (Diptera: Tephritidae) larvae, reared in artificial diets with different protein sources. Larvae of A. fraterculus were reared in the diets based on 1) raw wheat germ (control); 2) whole rice flour; 3) corn flour; and, 4) whole wheat flour + soybean meal. The larvae were used for the development of D. areolatus, to evaluate the number of offspring/female, emergence rate, sex ratio, egg-adult period, adult weight posterior tibia length and longevity. Larvae of A. fraterculus reared in the diets based on wheat germ and corn flour obtained a greater number of offspring, with shorter duration of egg-adult period for males and females. In diets with rice flour and corn flour, A. fraterculus larvae generated adults of D. areolatus with greater weight, longer tibia length and higher sex ratio, whereas larvae reared in wheat flour + soybean meal diet had a lower sex ratio. The diets based on rice flour and corn are the most appropriate for multiplication of the parasitoid.

Population Dynamics of Drosophila suzukii (Diptera: Drosophilidae) in Berry Crops in Southern Brazil

Drosophila suzukii (Matsumura) is an invasive species originating in Southeast Asia and considered a severe pest in berry crops in several countries of the Northern Hemisphere and Europe. In South America, the species was first detected in 2013. The objective of the study was to monitor the seasonal activity of D. suzukii in commercial crops of blackberry, strawberry guava, surinam cherry, blueberry, and strawberry during two consecutive harvests and in three properties in the Southern region of Brazil during the 2015/2016 and 2016/2017 harvests, with the aid of traps baited with apple cider vinegar. The highest population peaks were observed during late spring to mid-fall in all areas and plant species studied. It was verified that temperature is the factor that most influenced the seasonal activity of D. suzukii in the field, promoting low catches of the species during winter. However, even during periods of low temperatures (winter period), the presence of D. suzukii in the crops was verified, demonstrating the species' ability to stay in place from year to year, surviving in alternative hosts such as Eriobotrya japonica, a common species in the region. The information on the time of the highest occurrence of the pest in different hosts presented in this study provides the basis for decision-making in relation to the management of D. suzukii, to avoid further economic damage.

An Accurate Data Preparation Approach for the Prediction of Mortality in ACLF Patients using the CANONIC Dataset

The incidence of chronic liver disease has increased in Europe and can lead to Acute on Chronic Liver Failure (ACLF) which is associated with high levels of mortality due to multisystem organ failure. The characteristics of the ACLF patients can change very rapidly within a short period of time. Continuous assessment of their recovery status is critical for clinicians to adjust and deliver effective treatment. The aim of this paper is to validate the usefulness of a data preparation approach by combining different criteria to replace missing values, balance target-class variables, select useful patient characteristics and optimise hyperparameters of machine learning models for the prediction of ACLF associated mortality rates. A key step in the data preparation is a feature selection Mutual Information (MI) based multivariate approach to build smaller, and yet equally and in some cases more informative, subsets of patient characteristics than those frequently proposed for the prediction of mortality, from patients with ACLF in the CANONIC dataset. The usefulness of the data preparation approach proposed to predict mortality was evaluated by training the XGBoost and Logistic Regression models with the prepared data. Evaluations of the models trained using a test set provided evidence of an overall high accuracy in the prediction of the mortality rates of patients for days after their diagnosis, and in some cases even higher when reduced and more informative subsets of patient characteristics were found.

Strategies for Establishing a Rearing Technique for the Fruit Fly Parasitoid: Doryctobracon brasiliensis (Hymenoptera: Braconidae)

Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) is the most important pest in South American orchards. When control measures are not adopted, this pest can cause losses of up to 100%. Doryctobracon brasiliensis (Szépligeti) (Hymenoptera: Braconidae) is a larval-pupal endoparasitoid that can be used as a native biological control agent against A. fraterculus. This study aimed to develop a rearing technique for D. brasiliensis in larvae of A. fraterculus. Trials were carried out to: 1) determine the optimal instar for parasitism, 2) define the exposure time of larvae to parasitoids, 3) determine the density requirements of A. fraterculus larvae offered to each parasitoid, and 4) evaluate the effect of diet on adults of D. brasiliensis. In all trials, we evaluated the number of offspring, parasitism rate, and sex ratio. Moreover, in the experiment to investigate the effects of diet, we determined the longevity of males and females. In both choice and nonchoice parasitism tests, the parasitoids preferred third-instar larvae of A. fraterculus over second- and first-instar larvae. An exposure time of 12 h of A. fraterculus larvae produced larger numbers of parasitoids and higher parasitism rates. The density of 15 larvae of A. fraterculus to each female of D. brasiliensis produced a larger number of offspring. A supply of honey solution (20 and 50%) to the parasitoids yielded the highest number offspring and resulted in greater longevity. Our findings can be used to support the development of a mass rearing protocol for D. brasiliensis.

Rearing two fruit flies pests on artificial diet with variable pH

Fruit flies (Diptera: Tephritidae) are considered the main fruit pests worldwide. In Brazil, two species are predominant: the South American fruit fly, Anastrepha fraterculus and the Mediterranean fruit fly, Ceratitis capitata. In this study, we evaluated the effect of artificial diets with variable pH in their larval development and adult performance. The experiments were carried out in the laboratory at 25 ± 2 °C, 70 ± 10% RH and 12:12h (L:D) photoperiod. Semisolid diets with pH values of 6.0, 5.0, 4.0, 3.0, 2.0, 1.5, and 1.0, adjusted by adding hydrochloric acid were tested. Results indicated that the diet with pH 6.0 did not support larval development of both species of fruit fly. Diets with greater acidic pH values did not allow egg, larvae or pupae development and adult reproduction of A. fraterculus. For C. capitata , the pH of artificial diet exerts greater influence compared to A. fraterculus on the duration and viability of the larval stage, number of pupae, sex ratio and longevity of males.

Development and reprotuction of Spodoptera eridania on natural hosts and artificial diet

The development and reproductive potential of Spodoptera eridania (Stoll, 1782) (Lepidoptera, Noctuidae) was compared on natural and artificial diets. Its biology was determined under laboratory conditions, providing an artificial diet, leaves of white clover and the peach cultivar 'Chimarrita' and fruits and leaves of the apple cultivar 'Gala'. Larvae of S. eridania could not complete their biological cycle when fed on apple fruits or peach leaves. The artificial diet provided the shortest development time, with a cycle of 28.5±0.14 days from egg to adult and 37.3% total viability. Apple leaves led to a longer development time from egg to adult (62.8±1.22 days) and lower total viability (23%) and white clover provided the highest total viability (54.3%). The results showed that S. eridania can use white clover and apple leaves to develop normally in apple orchards. The reduction of food sources such as white clover used by the larvae results in infestation and damage to fruits from "test bites".

Oviposition of fruit flies (Diptera: Tephritidae) and its relation with the pericarp of citrus fruits

Fruit flies (Diptera: Tephritidae) represent a threat to fruit growing worldwide, mainly the citrus culture, however, biological studies show that fruit flies are not perfectly adapted to this host. This study investigated oviposition of Anastrepha fraterculus (Wiedemann, 1830) and Ceratitis capitata (Wiedemann, 1824) and its relation with the pericarp of citrus fruits. We evaluated the relationship between depth of oviposition of A. fraterculus and C. capitata and epicarp thickness of orange [Citrus sinensis (L.) Osbeck)] 'Navelina' and tangerine [C. reticulata (L.)] 'Clemenules' and the influence of fruit mesocarp of tangerine 'Clemenules' on oviposition of these species. The study was conducted under controlled conditions of temperature (25 ± 2 °C), relative humidity (70 ± 10% RH) and photophase (12 h). A. fraterculus and C. capitata laid their eggs in the flavedo region of orange 'Navelina' and between the albedo and flavedo of tangerine 'Clemenules'. When fruits with mesocarp exposed were offered, there was no oviposition by both fruit fly species. The results show that epicarp thickness of citrus fruits did not influence oviposition of A. fraterculus and C. capitata as oviposition did not occur only in the presence of the mesocarp, suggesting that other factors are involved in oviposition of these species.

Biology and fertility life table of Eriopis connexa, Harmonia axyridis and Olla v-nigrum (Coleoptera: Coccinellidae)

The coccinellids Eriopis connexa (Germar), Harmonia axyridis (Pallas) and Olla v-nigrum (Mulsant) are important natural biological control agents. The purpose of this paper was to study the biology and create a fertility life table of these three coccinellid species. For the biology study, 50 insects/species were used and kept in groups of 10 in glass vials (2300 cm3). For the three species studied, the viability of the total cycle varied from 45 to 50%. O. v-nigrum was the species which presented the longest oviposition period. However, H. axiridis demonstrated the best reproductive performance and ability of population growth in each generation. In conclusion, the use of commercially obtained pollen and A. kuenhiella eggs enables the development of coccinellids E. connexa, H. axyridis and O. v-nigrum under laboratory conditions, since the insects completed their biological cycle and originated adults with good reproductive performance.

Development of Anastrepha fraterculus (Diptera: Tephritidae) Related to the Phenology of Blueberry, Blackberry, Strawberry Guava, and Surinam Cherry Fruits

Anastrepha fraterculus (Wiedemann, 1830) is the main pest of temperate climate orcharding. The study investigated the development of A. fraterculus related to phenological stage of blueberry, blackberry, strawberry guava, and Surinam cherry trees. The phenological stages I (green fruits), II (intermediate ripening stage of fruits), and III (fruits close to harvesting) were determined, and they are from 8th, 10th, and 11th week; 6th, 8th, and 9th week; 8th, 13th, and 16th week; and 5th, 6th, and 7th week after the first flowering of blueberry, blackberry, strawberry guava, and Surinam cherry trees, respectively. We collected fruits from orchards to determine the infestation index using the formula: number of pupa/fruit weight. To investigate the development of A. fraterculus, we determined the following biological parameters: egg-to-adult period, weight of pupae, oviposition period, fecundity, number of pupae, and number of infested fruits. The infestation index for the fruits collected in the field was greater in strawberry guava and Surinam cherry fruits. In the laboratory, the development of A. fraterculus occurred in stage III of blueberry. In blackberry, besides stage III, we also observed the development in stage II, however, at lower infestation. In strawberry guava, the development of A. fraterulus occurred in stages II and III, and the development in both stages was similar. For Surinam cherry, the development occurred in the three phenological stages with similar values for biological parameters. Overall, of the four hosts studied, the strawberry guava and Surinam cherry fruits allowed a better biological development of A. fraterculus, corroborating its preference for fruits native to Brazil.

Aphid Species and Population Dynamics Associated with Strawberry

Aphids are among the major pests associated with strawberries in Southern Brasil. In this study, we identified the main species that occur in strawberry fields in the states of Paraná and Rio Grande do Sul, Brasil. We also compared the effectiveness of different sampling methods and studied the population dynamics of aphid species during two strawberry crop cycles in the municipality of Pinhais, state of Paraná, Brasil. Chaetosiphon fragaefolii (Cockerell) and Aphis forbesi Weed were the main species associated with strawberry. The method of hit plant and the Möericke trap showed equal effectiveness to capture wingless and winged insects. The peak population of aphids in the state of Paraná occurred from September to November. This information can help producers to implement strategies to monitor and control the major aphid species that occur in strawberry culture.

Development and Leaf Consumption by Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) Reared on Leaves of Agroenergy Crops

Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) is a polyphagous pest that threatens more than 24 species of crop plants including those used for biodiesel production such as Ricinus communis (castor bean), Jatropha curcas (Barbados nut), and Aleurites fordii (tung oil tree). The development and leaf consumption by S. cosmioides reared on leaves of these three species were studied under controlled laboratory conditions. The egg-to-adult development time of S. cosmioides was shortest when reared on castor bean leaves and longest when reared on tung oil tree leaves. Larvae reared on castor bean and Barbados nut leaves had seven instars, whereas those reared on tung oil tree leaves had eight. Females originating from larvae reared on castor bean and Barbados nut leaves showed greater fecundity than did females originating from larvae reared on tung oil tree leaves. Insects fed on castor bean leaves had shorter life spans than those fed on tung oil tree and Barbados nut leaves although the oviposition period did not differ significantly. The intrinsic and finite rates of increase were highest for females reared on castor bean leaves. Total leaf consumption was highest for larvae reared on tung oil tree leaves and lowest for those reared on Barbados nut leaves. We conclude that castor bean is a more appropriate host plant for the development of S. cosmioides than are Barbados nut and tung oil tree.

A new procedure for the construction of flow-through optodes. Application to determination of copper (II)

A new procedure for constructing an optical fibre reflectance, bulk optode membrane type, sensor is presented. The optode membrane consists of a plasticized poly (vinyl chloride) membrane in which the ionophore is dissolved, entrapped in a cellulose support. The new optode with the dye indicator 1-(2-pyridylazo)-2-naphthol (PAN) was incorporated in a new flow-through cell and the injection system was optimized to determine Cu (II) at 567 nm in the range 5 x 10(-5)-10(-3) M. The response was reproducible and the optode can be regenerated using 10(-2) M EDTA followed by water. The method was applied to the determination of copper in real samples.

Totally intra-articular arthroscopic knot: push and twist technique

Many techniques and instruments have been developed for performing arthroscopic repair with sutures. The technique for performing and completing arthroscopic knots are essentially extra-articular. Catching soft tissue, breakage, and damage of the suture and tightening inside the cannula are the essential problems with the extracorporeal knots. We describe an arthroscopic technique for making knots totally intracorporally based in the creation of intra-articular loops that can help the surgeon in repairs of different structures.

Flow-injection spectrofluorimetric determination of flufenamic and mefenamic acid in pharmaceuticals

Two sensitive and rapid flow-injection (FI) spectrofluorimetric methods are proposed for the determination of flufenamic acid (FF) and mefenamic acid (MF), based on the formation of complexes of these compounds with A1(III) in an ethanolic medium. The calibration graphs resulting from the measurements of the fluorescence at lambda exc = 351 nm and lambda em = 440 nm, and lambdaexc = 355 nm and lambda em = 454 nm for the complexes with FF and MF, respectively, are linear over the range 0.030-1.20 micrograms ml-1 for FF and 0.30-16.1 micrograms ml-1 for MF. The methods have been applied to the determination of these drugs in pharmaceutical preparations.

Flow-injection spectrophotometric determination of piroxicam

Two flow-injection analysis (FIA) methods are proposed for the determination of piroxicam. The first involves measurement of the UV absorbance of a solution containing the drug, methanol and hydrochloric acid at 332 nm; in the second method a Fe(III)-piroxicam complex is formed in a methanolic medium and the absorbance is measured at 520 nm. In both methods, the peak height is used as a quantitative parameter and piroxicam is determined over the ranges 0.5-15 and 30-500 microgram ml-1, respectively. The methods have been applied to the routine determination of the drug in dosage forms.

Determination of penicillamine or tiopronin in pharmaceutical preparations by flow injection analysis

Two flow injection analysis (FIA) methods, using spectrophotometric detection, are proposed for the determination of penicillamine or tiopronin [N-(2-mercaptopropionylglycine)]. The procedures are based on the formation of yellow complexes between these thiol-containing drugs and Pd(II), in a 1 M or 0.25 M HCl medium, respectively. With peak height as a quantitative parameter, penicillamine is determined over the range 1.0 x 10(-5)-7.0 x 10(-4) M; for tiopronin the range is 1.0 x 10(-5)-6.0 x 10(-4) M. The methods have been applied to the routine determination of the drugs in pharmaceutical preparations.

Kinetic determination of iodide in pharmaceutical and food samples

A kinetic method for the determination of iodide based on its inhibitory effect on the Pd(III) catalysed reaction between ethylenediaminetetraacetic acid (EDTA)-Co(III) and the hypophosphite ion is described. The reaction was followed spectrophotometrically by measuring the decrease in the absorbance at 540 nm. Under the optimum experimental conditions of 2.6 x 10(-3) mol dm(-3)Co(III)-EDTA, 0.4 mol dm(-3)H2PO2-, pH 3.2 (adjusted with Britton-Robinson buffer), 0.57 micrograms ml(-1) Pd(III) and 20 +/- 0.2 degrees C, iodide was determined in the range 2-28 ng ml(-1). The method was applied to the determination of iodide in pharmaceutical products, iodinated salts, cow's milk and infants' powdered milk.

Immunocytochemical localization of luteinizing hormone-releasing hormone (LHRH) in the brain and nervus terminalis of the adult and early neonatal gray short-tailed opossum (Monodelphis domestica)

Luteinizing hormone-releasing hormone (LHRH) was detected by immunocytochemical procedures in cells and fibers in the brain and in the nervus terminalis of the adult and neonatal gray, short-tailed opossum (Monodelphis domestica). As in several species of eutherian mammals, LHRH-immunoreactive cells and fibers were seen in the medial septal nuclei, nucleus, and tract of the diagonal band and olfactory tubercle. Surprisingly, few LHRH-immunoreactive cells were found in the hypothalamus or in the preoptic area in either the adult or neonate. LHRH-immunoreactive fibers were seen in these regions and were numerous in the median eminence. The nervus terminalis in the gray opossum showed several distinctive characteristics. Immunoreactive and nonreactive cells, in ganglia along the peripheral and intracranial course of this nerve, were accompanied by thick fascicles of LHRH fibers and frequently lay adjacent to blood vessels. No LHRH-immunoreactive branches of the nervus terminalis were found in contact with the vomeronasal nerves as they traversed the medial surfaces of the main olfactory bulbs en route to the accessory olfactory bulbs. The LHRH-immunoreactive fibers in the central roots of the nervus terminalis formed a compact bundle on either side of midline, which coursed obliquely from clusters of ganglion cells on the ventromedial surface of the olfactory bulbs into the septum. Traced through serial sagittal sections, LHRH-immunoreactive fibers, in continuity with those in the triangular nucleus of the septum, ran down and around the rostral face of the anterior commissure and fanned out into the medial preoptic area. As previously observed in the fetal guinea pig and rat, LHRH was detected in ganglion cells of the nervus terminalis of the newborn gray opossum preceding its detection in any other area of the brain.

Distribution of luteinizing hormone-releasing hormone in the nervus terminalis and brain of the mouse detected by immunocytochemistry

Immunoreactive luteinizing hormone-releasing hormone (LHRH) was localized in a relatively large number of ganglion cells and fibers of the nervus terminalis of neonatal and adult mice, indicating that this nerve is a substantial source of LHRH in the mouse brain. Whole-head specimens of neonatal mice, prior to calcification of the cranium, revealed an extensive distribution of LHRH neurons and fine fibers throughout the peripheral, intracranial, and central parts of the nervus terminalis. The most striking difference between the neonatal and adult animals, in the nervus terminalis, was the increase in immunoreactive axons that made up the fiber bundles of this nerve. In the adult mouse, the intracranial and central projections were composed of thick fascicles of immunoreactive axons, ensheathed by glial cells and accompanied by ganglia that contained both LHRH-reactive and nonimmunoreactive neurons. LHRH-immunoreactive cells and axons were seen in a branch of the nervus terminalis that coursed along the medial, posterodorsal aspect of the olfactory bulb and in branches of this nerve that accompany the vomeronasal nerves to the accessory olfactory bulb. A few LHRH neurons and many immunoreactive processes were seen in the accessory and main olfactory bulbs. LHRH-reactive neurons were seen in the hypothalamus and extrahypothalamic structures. Examination of adult mouse brains revealed a pattern of distribution and number of immunoreactive neurons similar to that seen in the neonate. However, many more LHRH-reactive axons were seen in all areas of the brain of the mature animal.