Melatonin associated with a high-fat diet during pregnancy and lactation prevents liver changes in the offspring.

In the present study, we set out to determine whether melatonin combined with a high-fat diet during pregnancy and lactation can prevent liver disorders in offspring. Forty rats were divided into four groups: DC - pregnant rats submitted to the standard diet; DC + Mel - pregnant rats submitted to the standard diet combined with melatonin; HFD - pregnant rats submitted to a high-fat diet; HFD + Mel - pregnant rats submitted to a high-fat diet combined with melatonin. Morphophysiological and biochemical parameters were analyzed. Melatonin (5 mg/kg) was administered intraperitoneally. The HFD group offspring showed an increase in AST, ALT, alkaline phosphatase, cholesterol, triglycerides, LDL and glucose levels, and a reduction in HDL and lipase levels. In the liver obseved steatosis, hepatocellular ballooning, increased lobular parenchyma and reduced non-lobular parenchyma, beside reduced liver glycogen and fibrosis. These changes were not observed in the HFD + Mel group. In conclusion, melatonin combined with a high-fat diet preserves the liver architecture and function in the offspring.

Bacillus thuringiensis affects reproductive capacity of adult rat offspring.

We investigated the effects of B. thuringiensis-based biological insecticides, XenTari and Dipel, and deltamethrin on the reproductive development of pups of pregnant rats. Twenty 90-day-old pregnant rats were divided randomly onto four equal groups: control group (GC) administered only water; XenTari group (GX) administered 1 mg XenTari (containing Cry1Ac toxin of B. thuringiensis)/100 g body weight; Dipel group (GDi) administered 1 mg Dipel (containing Cry1Aa, Cry1Ab and Cry1Ac toxins of B. thuringiensis)/100 g body weight; and a deltamethrin group (GDe) administered 2 mg deltamethrin (0.08 ml Keshet 25EC)/kg body weight as a positive control. Insecticides were administered by gavage at doses of 1 mg/100 g/day (GX and GDi), and 2 mg/kg/day (GDe) during pregnancy and lactation. Treatment with both biologic and synthetic insecticides reduced the weight gain of the mothers. The biological insecticides reduced the number, weight and length, and increased malformation and mortality of the offspring. In female offspring for all three groups administered insecticides, opening of the vagina was delayed, metestrus was increased and estrogen and progesterone levels were reduced compared to proestrus, estrus and metestrus of the cycle. The ovaries of female offspring of all three groups administered insecticides contained numerous tertiary and atretic follicles, few corpora lutea, primary and secondary follicles, and reduced estrogen receptors compared to controls. In male offspring, all three groups exposed to insecticides exhibited reduced testosterone levels. Histopathological changes in the testes including vacuolation and desquamation of the seminiferous epithelium were observed only in the GX and GDi groups. The number of androgen receptors was reduced significantly in the testes and testicular morphometry revealed reduced tubule diameter, height of the seminiferous epithelium and total tubule length compared to the control. The biological insecticides, XenTari and Dipel, administered in sublethal doses to pregnant rats, caused reproductive changes in the offspring similar to those of the insecticide, deltamethrin.

Effect of swimming exercise, insulin-associated or not, on inflammatory cytokines, apoptosis, and collagen in diabetic rat placentas.

Physical exercise is an important therapeutic agent for women with diabetes during gestation. However, its histophysiological consequences for the placenta remain unclear. In this study, we evaluated the expression of VEGF-A, IL1ß, TNFα, and type I collagen in the placentas of diabetic rats subjected to a swimming program. Thirty rats were divided into the following groups: CG, pregnant nondiabetic rats; CEG, nondiabetic pregnant rats subjected to swimming; DG, pregnant diabetic rats; DEG, pregnant diabetic rats subjected to swimming; DIG, pregnant diabetic rats treated with insulin; DIEG, pregnant diabetic rats treated with insulin and subjected to swimming. Diabetes was induced using streptozotocin [50 mg/kg intraperitoneally (i.p.)], and insulin was administered at a dose of 5 U/day i.p. (2 U at 10 am and 3 U at 7 pm) in the DIG group; in the DIEG group, insulin was administered at a dose of only 2 U/day at 7 pm. The rats were sacrificed on the 20th day of gestation. There was an increase in the expression of IL-1ß, TNF-α, VEGF-A, and type I collagen and a higher apoptotic index in the placentas of the DG and DEG groups, but there was a reduction in glycemia in the latter group. In the DIG and DIEG groups, the levels remained similar to those of the control; however, in these groups the reduction was more significant for all analyzed parameters. Therefore, in rats induced to diabetes during pregnancy, swimming, although reducing glycemic levels, did not prevent immunohistochemical changes in the placenta, suggesting the need for a multidisciplinary protocol associated with traditional pharmacological treatment.

Melatonin Administration Prevents Placental and Fetal Changes Induced by Gestational Diabetes.

Gestational diabetes mellitus (GDM) promotes changes in the placenta and fetuses, due to oxidative stress. Antioxidants can reduce oxidative stress in the placenta. We tested the hypothesis that melatonin (Mel) can prevent these effects in the placenta and fetuses, analyzing their histology, histochemistry, morphometry, and immunohistochemistry. Thirty albino rats were used, divided into groups: CG-pregnant non-diabetic rats; GD-pregnant diabetic rats; GD + Mel-pregnant diabetic rats treated with melatonin. Diabetes was induced by streptozotocin at a dosage of 50 mg/kg i.p. Melatonin was administered in daily injections of 0.8 mg/kg i.p. Melatonin prevented the placental weight and fetal weight and length from increasing, in addition to histomoformetric, histochemical, and immunohistochemical changes in the placentas, compared to the placentas of diabetic females (GD). Thus, we conclude that melatonin has a great potential to prevent placental changes due to GDM.

Follicle-stimulating hormone mediates the consumption of serum-derived glycogen by bovine cumulus-oocyte complexes during in vitro maturation.

BACKGROUND AND AIM: Oocyte in vitro maturation (IVM) is an appealing approach for several assisted reproductive technologies and dissecting oocyte maturation. Nonetheless, IVM leads to lower developmental competence and usually relies on undefined, serum-containing media. Therefore, biochemical profiling aimed to explore fluctuations in IVM media content during the acquisition of oocyte developmental competence. MATERIALS AND METHODS: Bovine cumulus-oocyte complexes (COCs) underwent IVM in TCM199 medium with Earle's salts, supplemented with 2.0 mM L-glutamine, 10% fetal bovine serum, antibiotics, and 0.05 IU/mL porcine follicle-stimulating hormone (FSH+) or vehicle control (CTL) medium for 22 h. RESULTS: FSH withdrawal (CTL) diminished several processes associated with the acquisition of oocyte developmental competence, such as reduced cumulus cell expansion, diminished estradiol synthesis (FSH+: 116.0±0.0 pg/mL vs. CTL: 97.6±18.0 pg/mL), and lower oocyte nuclear maturation rate (FSH+: 96.47% vs. CTL: 88.76%). Fresh media formulations (i.e., TCM199 with FSH or vehicle) were indistinguishable under biochemical profiling threshold conditions. Biochemical profiling showed similar total protein and lipid concentrations between groups. Further, total sugar concentrations diminished from fresh media to their post-IVM counterparts, albeit in an FSH-independent manner. Glycogen concentrations remained unaltered after IVM within CTL media, albeit were substantially lower after IVM under FSH+ conditions. CONCLUSION: FSH mediates the consumption of serum-derived glycogen by bovine COCs during IVM and implies that serum-free media should contain increased glucose concentrations to facilitate the acquisition of oocyte developmental competence.

Renal and hepatic changes in the offspring of rats that received biological insecticides during pregnancy and lactation.

Bacillus thuringiensis insecticides have been considered safe, being an alternative to the use of synthetic insecticides. However, studies have shown the effects of Bt Cry toxins on various organs, compromising their functions. The objective of this work was to test whether the administration of biological insecticides based on B. thuringiensis in pregnant rats will cause histopathological changes in the liver and kidneys, as well as in the levels of toxicity biomarkers, of their puppies in adulthood. Twenty rats, 90 days old, were used, divided into four groups: GC - Pregnant rats, GX - Pregnant rats that received XenTari®, GDi - Pregnant rats that received Dipel® and GDe - Pregnant rats that received deltamethrin. Insecticides were administered by gavage at a dosage of 1 mg/100 g/day (GX and GDi), and 2 mg/Kg/day (GDe) during pregnancy and lactation. In the animals of the groups whose matrices received the insecticides, there was a reduction in the levels of the biomarkers of toxicity alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea and creatinine, about the control group. The biological insecticides promoted histopathological changes in the liver, with the presence of portal vein, centrilobular and sinusoidal capillaries congestion, and in the kidney, presence of cortical congestion and reduction of the subcapsular space. Histochemical evaluation in the liver demonstrated a significant reduction in glycogen in the groups that received insecticides when compared to the control group, whereas for collagen fibers in both the liver and the kidneys, no differences were observed between the experimental groups. The morphometry of the liver revealed a significant reduction in the lobular parenchyma and an increase in the non-lobular parenchyma, and in the kidney, there was a reduction in the diameter and volume of the glomerulus and Bowman's capsule of the animals whose matrices received both biological and synthetic insecticides. Thus, it is concluded that the biological insecticides XenTari® and Dipel® in sublethal doses in pregnant rats promote changes in the liver and kidney of the offspring similar to the insecticide deltamethrin, which extend into adulthood.

Histological, histochemical and energy disorders caused by R-limonene on Aedes aegypti L. larvae (Diptera: Culicidae).

The study evaluated the effects of R-limonene, in sublethal concentration, on the histology, histochemistry, biochemistry, and carbohydrates and proteins levels in the third instar Aedes aegypti larvae. The R-limonene (LC50 of 27 ppm) and control groups were analyzed 12 and 24 h after the beginning of treatments. The midgut of the control larvae was composed of cylindrical and elongated cells with a spherical and central nucleus and regenerative cells with a pyramidal shape. After 12 h of treatment, columnar cells, protuberances, and cytoplasmic vacuolization were found. However, 24 h after treatment, complete disorganization of the epithelium was observed. There was a positive reaction in all treatments for the presence of glycogen. However, the midgut of larvae treated with R-limonene showed higher levels. For the total protein, positive marking occurred in all groups evaluated, with higher levels in treatments and the lowest in control 12 h. The levels of total protein and glycogen increased in the treated larvae compared to the 12 h control. Besides, a reduction in total sugar levels was observed in the treated larvae compared to controls 12 and 24 h, being more evident in the last one. Therefore, these results demonstrate that R-Limonene caused pathological changes in the epithelium of the A. aegypti midgut at histophysiological and biochemical levels.

Essential oil toxicity on biological and reproductive parameters of Alabama argillacea (Hübner) (Lepidoptera: Erebidae).

Several studies have demonstrated the effects of essential oils on insect pests. These effects vary and affect fundamental parameters for the survival of these organisms. However, there is a scarcity of research on the effect of these substances on Alabama argillacea (Hübner) (Lepidoptera: Erebidae), the main defoliating pest of cotton (Gossypium hirsutum L.). Thus, the present study aimed to evaluate the activity of essential oils from Litsea cubeba (Lour.) Pers., Melaleuca alternifolia Cheel, Juniperus virginiana L., and Mentha spicata L., on the biological and reproductive parameters of A. argillacea and the consequent effects on the gonads of both males and females of this pest. All essential oils presented toxicity by contact in third instar larvae of A. argillacea, causing a reduction in the weight of larvae and pupae, as well as affecting the number and viability of eggs. These essential oils changed the histochemistry of the testicles, and M. alternifolia, J. virginiana, and M. spicata also affected their morphology. The histochemistry of the ovarioles was altered by the essential oils from M. alternifolia, J. virginiana, and L. cubeba. Thus, the essential oils tested in the present work are promising for the control of A. argillacea, as they are toxic and affect the development and reproduction of this key pest of cotton.

Immunohistochemical and histophysiological study of prolonged use of nandrolone on reproductive organs and fertility.

We investigated possible changes in morphology and immunohistochemistry of the uterus and ovaries of rats caused by nandrolone (ND); we also investigated effects on fertility. We used 30 rats divided into three experimental groups: control (C), control vehicle (CV) and 5 mg/kg ND. Rats treated with ND exhibited loss of estrous cyclicity with predominance of the estrus phase, increased body weight and an organosomatic index that was decreased for the ovaries, but increased for the uterus. In the ovary, we observed a reduction in primary and secondary follicles and an increase in tertiary follicles; no corpora lutea were observed. Estrogen and progesterone levels were reduced. In the uterus, the endometrium was edematous with hyperplasic glands. The cytokines, TNFα and IL6, and the apoptotic index were increased in rats treated with ND. VEGF-A was increased in the ovaries and decreased in the uterus. We conclude that ND disrupts ovarian and uterine histophysiology by establishing an anovulatory and inflammatory condition, which directly affects reproduction.

Histomorphometric and immunohistochemical evaluation of the frontal cerebral cortex in diabetic rats after treatment with melatonin / Avaliação histomorfométrica e imuno-histoquímica do córtex cerebral frontal em ratos diabéticos após o tratamento com melatonina

The central nervous system is vulnerable to complications caused by diabetes. These complications lead to increased oxidative stress in the brain, resulting in damage to the cerebral cortex, among other regions. Insulin and hypoglycemic agents are still the most widely used treatments. However, current research with an experimental model of diabetes suggests the use of antioxidants, such as melatonin. Thus, we tested the hypothesis that exogenous melatonin may decrease or prevent the effects of diabetes in the frontal cortex of the rat brain. Fifty albino rats were allocated into five groups: GC = rats without diabetes induction, GD = diabetic rats induced by streptozotocin, GDM = streptozotocin-induced and melatonin-treated diabetic rats, GDI = diabetic rats induced by streptozotocin and treated with insulin, GDMI = diabetic rats induced by streptozotocin and treated with melatonin and insulin simultaneously. Diabetes was induced by intraperitoneal administration of streptozotocin (60mg/kg). Insulin (5U/day) was administered subcutaneously and melatonin (10mg/kg) by drinking water; both treatments last days after. We analyzed animals' weight, the cytokines IL-6 and TNF-α, apoptosis, glycogen, and did morphometry and histopathology of the frontal cortex were analyzed. The results showed that the cerebral cortex of the diabetic animals presented axonal degeneration, reduced number of neurons in the cortex, reduced glycogen, increased IL-6 and TNF-α expression, high apoptotic index, and reduced animal weight and the brain. Treatment with melatonin associated or not with insulin prevented such effects. Thus, we conclude that melatonin associated with insulin may be an alternative for avoiding the impact of diabetes in the brain's frontal cortex.(AU)

O sistema nervoso central é vulnerável a complicações originadas pelo diabetes estresse oxidativo no cérebro e resultando em lesões no córtex cerebral, dentre outras regiões. A insulina e hipoglicemiantes ainda são os tratamentos mais utilizados, entretanto, pesquisas atuais com modelo experimental do diabetes sugerem a utilização de antioxidantes como, por exemplo, a melatonina. Assim, testamos a hipótese de que a melatonina exógena pode diminuir ou prevenir os efeitos do diabetes no córtex frontal do cérebro de ratos. Foram utilizados 50 ratos albinos, divididos em 5 grupos: GC = ratos sem indução ao diabetes, GD = ratos induzidos ao diabetes pela estreptozotocina, GDM = ratos induzidos ao diabetes pela estreptozotocina e tratados com melatonina, GDI = ratos induzidos ao diabetes pela estreptozotocina e tratados com insulina, GDMI = ratos induzidos ao diabetes pela estreptozotocina e tratados com melatonina e insulina simultaneamente. O diabetes foi induzido pela administração intraperitoneal de estreptozotocina (60mg/kg). A insulina (5U/dia) foi administrada por via subcutânea e a melatonina (10mg/kg) pela água de beber. Ambos tratamentos foram realizados durante 30 dias após a indução. Foram analisados o peso dos animais, do cerebro, as citocinas IL-6 e TNF-α, apoptose, glicogênio, além da morfometria e histopatologia do córtex frontal. Os resultados mostraram que o córtex cerebral dos animais diabéticos apresentou degeneração axonal, redução do número de neurônios no córtex, redução do glicogênio, aumento da expressão do IL-6 e TNF-α, elevação do índice apoptótico, além da redução do peso dos animais e do cérebro. O tratamento com melatonina associada ou não a insulina preveniu tais efeitos. Assim, concluímos que a melatonina associada ou não a insulina pode ser uma alternativa na prevenção dos efeitos do diabetes no córtex frontal do cérebro.(AU)

Side effects of a mixture of essential oils on Psyttalia concolor.

Integrated Pest Management programs do not always prioritize natural enemies when selecting control methods; too often these important pest reducing agents are negatively affected by the action of other methods in agroecosystems. The aim of this research was to evaluate side effects of a bioinsecticide, developed from the mixture of cedar (Cedrus atlantica), eucalyptus (Corymbia citriodora) and lemon grass (Cymbopogon citratus) essential oils (EOs), in a ratio of 1:1:1, on Psyttalia concolor (Szèpligeti) (Hymenoptera: Braconidae) which is a parasitoid of some pests of the Tephritidae family, as Ceratitis capitata. The LD50 of the EOs mixture for C. capitata females was 3.09 µl/g, whereas the LD50 for P. concolor females was 20.45 µl/g which suggests the natural enemy is more tolerant to the EOs mixture. P. concolor parasitized L3 larvae of C. capitata through a voile treated with the mixture of EOs at 1.8% without causing any deleterious effects neither on the percentage of attacked hosts nor on the emergence rate, whereas at the highest concentration tested, 4.8%, decreased both parameters during the 2 first days after treatment. Semi-field assays showed that mixture of EOs was harmless to P. concolor when released 4 h after treatment whereas killed 55 ± 3.9% males and 37.5 ± 1.6% females of C. capitata. The mixture of EOs used jointly with lambda-cyhalothrin or kaolin, both compounds applied against C. capitata in conventional and organic farming, respectively, did not increase the toxicity and/or persistence against the pest.

Protective action of melatonin on diabetic rat testis at cellular, hormonal and immunohistochemical levels.

The aim of the present study was to analyze the effects of melatonin treatment on diabetic rat testes. Fifty albino rats were divided into the following groups: CG: control group; GD: placebo-induced and placebo-treated mice; GDI: insulin-induced and post-confirmation diabetes-induced rats; GDM: diabetes-induced and melatonin-treated post-confirmation mice and GDMS: diabetes-induced and melatonin-treated mice simultaneously. Melatonin was administered at a dose of 10 mg/kg in drinking water every day for 20 days at night. Diabetes was induced by streptozotocin (60 mg/kg) and confirmed after the fifth day of induction. Insulin was administered at 5 IU (international units)/day at different times of the day for 20 days. The testes were submitted to histopathological, morphometric, immunohistochemical and oxidative stress analysis. Melatonin moderately decreased glycemic levels, protected weight loss and morphometric changes in the testicles, increased antioxidant enzyme levels and stabilized plasma testosterone and androgen receptor levels and decreased inflammatory markers in the testicles. Showing its potential to mitigate diabetes effects.

Effect of essential oils of Mentha spicata L. and Melaleuca alternifolia Cheel on the midgut of Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae).

Agricultural pest control is a popular research topic, and essential oils are widely studied because they represent a promising alternative to synthetic insecticides. However, despite the increase in studies on pests, little work has been done on pesticide contamination of the predators feeding on insecticide-affected prey. Therefore, the objective of this study was to evaluate the effects of Lethal Dose 50 (LD50) from the essential oils of Mentha spicata L. and Melaleuca alternifolia Cheel on the histology, including histochemistry (from protein and carbohydrate analysis) and immunohistochemistry (from the evaluation of cellular apoptosis), of the midgut of fifth instar nymphs of Podisus nigrispinus (stinkbug) (Dallas). The periods of analysis were 12, 24, and 48 h after ingestion of Alabama argillacea Hübner caterpillars treated with the respective oils. The oil from M. spicata did not cause histological alterations or apoptosis in the insect. However, there was a reduction in the level of carbohydrates within the 48-h period. After 24 h, the oil of M. alternifolia caused an elongation of digestive cells and, after 48 h, cell lysis with the release of material into the lumen, suggesting tissue necrosis. The immunohistochemical study revealed no apoptotic process. There was a reduction in the neutral carbohydrate levels in the 24- and 48-h periods and in the number of regenerative cells, when compared to the control, after the period of 48 h. These results demonstrate that M. spicata oil has potential for use in cotton fields because it does not affect the vital characteristics of P. nigrispinus. However, the essential oil of M. alternifolia is not suitable for use as a pesticide because it is extremely toxic to predators.

Effect of melatonin on gonad and thyroid development of offspring of hypothyroid pregnant rats.

We investigated the effects of melatonin on rats with induced hypothyroidism during gestation as well as its effect on the development of the gonads of their offspring. Fifteen pregnant rats were divided into three groups: GC, rats without induced hypothyroidism; GH, rats with induced hypothyroidism; GHM, rats with induced hypothyroidism plus melatonin. Hypothyroidism was induced by oral administration of 6-propyl-2-thiouracil and melatonin was applied subcutaneously. Treatments were performed during gestation and lactation. For the matrices, we evaluated the number of pups, body weight gain, ovarian weight, thyroid weight, organosomatic index, thyroid stimulating hormone (TSH) dose and thyroid morphometry. For the pups, weight gain, TSH, weight, morphometry of the gonads and organosomatic index were analyzed, as well as the cell proliferation index. TSH was elevated only in the matrices of GH animals. Melatonin prevented reduction of ovarian and thyroid weight, number of pups, follicular diameter and thyroid epithelial proportion of the matrices with hypothyroidism. The offspring of rats of the GH group exhibited less body weight gain, gonad and thyroid weight, and gonad cell proliferation index compared to the offspring born of rats of the GC and GHM groups. Melatonin prevented the effects of maternal hypothyroidism on the offspring of rats.

Ultrastructure of the antennal sensilla of Alabama argillacea (Hübner, 1823) (Lepidoptera: Erebidae)

Abstract Insects have several types of sensilla, the characterization of which has been fundamental to understanding the mechanisms of sensory perception in different species. This study aimed to describe the ultrastructure of the sensilla present on the antennae of Alabama argillacea (Hübner, 1823) (Lepidoptera: Erebidae), an important pest of cotton (Gossypium hirsutum L.) crops, as well as their possible variation between sexes. To do this, the antennae of males and females of A. argillacea were analyzed using scanning electron microscopy. Sensilla morphometry was assessed using photomicrographs, from which the lengths and basal and apical diameters of sensilla were measured using the ImageJ program. Seven types of sensilla were identified on the antennae of A. argillacea: sensilla trichodea, sensilla chaetica, sensilla auricillica, sensilla coeloconica, sensilla styloconica, sensilla basiconica, and sensilla Böhm bristles. Differences between the sensilla of males and females were found in their lengths and basal diameters in the distal and proximal regions. This suggests that sensilla functionality may not only vary from one species to another, but also between sexes within the same species. Thus, further transmission electron microscopy and single sensillum recording studies may provide more detailed information on the sensilla of A. argillacea and their functions.

Immunological Parameters of the Pomacea lineata Spix, 1827 (Mollusca: Caenogastropoda) Exposed to Schistosoma mansoni Sambon, 1907.

INTRODUCTION: Pomacea lineata acts as the natural biological controller of Biomphalaria glabrata, the intermediate host of Schistosoma mansoni, as they are found in the same environment. However, there are no studies reporting an infection in P. lineata due to S. mansoni. Thus, this work investigated parameters related to the immunity of P. lineata after exposure for 24 and 48 h to S. mansoni under experimental conditions. METHODS: The F1 generation of these snails was used in this study. The total and differential counts of hemocytes, phenoloxidase, nitric oxide, total proteins, expression of TNF-α in hemocytes and histopathology of the head-foot organ were analyzed. RESULTS: Exposure to S. mansoni promoted an increase in the total number of hemocytes, an increase of granulocytes, a reduction of agranulocytes and hyalinocytes, an increase in phenoloxidase levels, total proteins and nitric oxide. There was TNF-α expression in the agranulocytes and granulocytes, increasing in intensity after exposure to the trematode. Head-foot histopathology revealed the presence of sporocytes in the fibromuscular layer surrounded by granulation tissue only within 24 h. At 48 h, there was marked fibrosis in this layer and little granulation tissue. CONCLUSION: Thus, we can conclude that P. lineata seems to trigger a series of immunological strategies in a very effective way that confers some resistance to S. mansoni.

Effect of metronidazole on placental and fetal development in albino rats.

Metronidazole is an antiprotozoal and antibacterial used in gynecology and obstetrics for the treatment of parasitic infections. However, despite having clinical use for more than three decades, questions about the safety of its use during pregnancy is not well understood. Thus, the present study evaluated the effect of metronidazole on placental and fetal development in pregnant rats. Metronidazole was orally administered by gavage at a dosage of 130 mg/kg for 7 and 14 days. Morphological analysis, morphometry and immunohistochemistry were performed at the implantation sites and placentas with 14 days of development. The results showed that in the treated group there was a significant reduction in the number of implantation sites, total placental disc area and constituent elements of the labyrinth and spongiotrophoblast layers. Histochemical analysis revealed no significant changes in the content of collagen, elastic and reticular fibers. The TUNEL test showed apoptotic activity in the implantation sites and placentas with 14 days of development independent of the treatment. There was no evidence of malformation in the neonates. However, there was a significant reduction in the number and weight of neonates in the group treated with metronidazole when compared to the control group. Thus, it is concluded that the administration of 130 mg/kg of metronidazole during pregnancy in rats, in addition to interfering with the number of implanted embryos, promotes changes in placental structure and interferes with fetal development. This suggests that this drug should be used with caution during pregnancy.

Composition and Toxicity of a Mixture of Essential Oils Against Mediterranean Fruit Fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae).

A natural insecticide developed from the mixture of the essential oils (EOs) of Cymbopogon citratus (DC.) Stapf (Poaceae), Cedrus atlantica (Endl.) Manetti ex Carriére (Pinaceae), and Corymbia citriodora (Hook.) K.D. Hill & L.A.S. Johnson (Myrtaceae) was studied. The mixture of oils caused high mortality (LD50 = 0.018 µl/insect) to the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), a globally important pest, after topical application on adults. Based on the chemical characterization of biopesticide using gas chromatography-mass spectrometry (GC-MS) analysis, many of the constituents had known insecticidal properties (the monoterpenes α-citronellal and E-citral and the sesquiterpernes α-himachalene and ß-himachalene, all at concentrations above 15%). Phytotoxicity tests on orange trees demonstrated that this natural product was harmless when the mixture was applied diluted in water with a surfactant. The mixture of EOs was also harmless (1, IOBC category) to the biological control agent responsible for reducing populations of tephritids, the parasitoid Psyttalia concolor (Hymenoptera: Braconidae), following exposure to treated orange trees in a semifield assay within a greenhouse, but killed 46.2% of C. capitata (Szépligeti) adults after 72 h. Our results suggest that mixture of EOs has potential for use as an adulticide against medfly, although the production price was exceedingly high compared with that of commercial synthetic insecticides. Therefore, we discuss the advantages and disadvantages related to the potential use of this natural insecticide.

Protective effect of exogenous melatonin in rats and their offspring on the genotoxic response induced by the chronic consumption of alcohol during pregnancy.

Maternal alcoholism can induce serious injuries in embryonic and fetal development. The metabolism of alcohol increases the production of free radicals and acetaldehyde, molecules capable of reacting with DNA, impairing organogenesis. Melatonin is a powerful antioxidant that can act as a protective agent against DNA damage caused by genotoxic agents, such as ethanol. This study evaluated the protective effect of exogenous melatonin in rats and their offspring on the genotoxic response induced by chronic alcohol consumption during pregnancy. Twenty-five pregnant rats were divided into the following groups: NC - Negative control; ET - Rats receiving ethanol (3 g/kg/day); ET+10 M - Rats receiving ethanol (3 g/kg/day) and melatonin (10 mg/kg/day); ET+15 M - Rats receiving ethanol (3 g/kg/day) and melatonin (15 mg/kg/day); PC - Positive control (40 mg/kg cyclophosphamide). The dams and 10 pups (five males and five females) from each group were anesthetized to collect blood and liver from the dams and blood, liver and brain of neonates to evaluate the frequency of DNA damage by the comet assay. Blood was also used for the micronucleus test. The results demonstrated a significant increase in DNA damage in the blood and liver cells of dams receiving ethanol and their offspring as well as in the brain of these neonates. Treatments with melatonin (10 and 15 mg/kg/day) significantly reduced the genotoxicity caused by ethanol in the blood of dams and neonates (males and females), liver of dams and male offsprings, and in the brain of female offsprings. It was shown that only the female offspring exposed to maternal alcohol consumption showed a higher frequency of micronuclei in polychromatic erythrocytes. Consequently, exogenous melatonin may be a promising therapeutic agent against genotoxic damage induced by alcohol; however, further studies are needed to confirm these benefits.

Labeling membrane receptors with lectins and evaluation of the midgut histochemistry of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) populations with different levels of susceptibility to formulated Bt.

BACKGROUND: Studies show that insects can adapt to the toxins of Bacillus thuringiensis under field and laboratory conditions through the development of resistance to the bacterium and its formulations. This has been demonstrated in the failure to control Tuta absoluta populations in Brazil. This study evaluated membrane receptors using peroxidase-labeled lectins and the midgut histochemistry of T. absoluta populations to assess susceptibility to the insecticides Bt fomulations. The histochemistry analysis used Periodic Acid-Schiff for glycogen and Ponceau Xylidine for total proteins. The presence of glucose/mannose and N-acetylgalactosamine (GalNAc) was analyzed using specific lectins. One susceptible and one tolerant population were used in the study; insects were exposed to the insecticide concentrations recommended by the manufacturers. The midgut was collected after an interval of 20 min and analyzed using optical microscopy. RESULTS: Bt fomulation interferes with the glycogen content, whereas XenTari® interferes with the protein content, irrespective of the level of susceptibility. High expression of GalNAc residues was observed using soybean lectin labeling, indicating a direct relationship between the glycosylation pattern and susceptibility to Bt fomulation in the Pelotas population. CONCLUSION: The use of Bt fomulation caused greater alterations in the larval intestinal histophysiology compared to the use of XenTari® . © 2018 Society of Chemical Industry.