Involvement of regional lymph nodes after penetration of Schistosoma mansoni cercariae in naive and infected mice

The parotid lymph nodes of naive and previously infected Balb/c mice were studied after, respectively, infection and re-infection with cercariae of Schistosoma mansoni via the ears. Schistosomula were able to pass through the lymph node by following the lymph flow or by penetrating the veins of the medullary cords. The number of nodal mast cells was higher from day 2 to 6 of primary infection; and from day 5 to 11 of re-infection. The amount of degranulating mast cells was significantly higher at day 4 of infection and at day 1 of re-infection. Eosinophils characterized the nodal inflammatory processes observed after day 5 in both primarily-infected and re-infected mice. However, only in the latter the eosinophils were able to adhere to the larval surface. In primarily-infected mice, no intranodal larva presented signs of degeneration. In contrast, in re-infected animals, some degenerating larvae were found inside eosinophilic infiltrates. The eosinophils reached the nodal tissue by migrating through the high endothelial venules and their collecting veins.

Ultrastructural alterations in adult Schistosoma mansoni caused by artemether

Progress has been made over the last decade with the development and clinical use of artemether as an agent against major human schistosome parasites. The tegument has been identified as a key target of artemether, implying detailed studies on ultrastructural damage induced by this compound. We performed a temporal examination, employing a transmission electron microscope to assess the pattern and extent of ultrastructural alterations in adult Schistosoma mansoni harboured in mice treated with a single dose of 400 mg/kg artemether. Eight hours post-treatment, damage to the tegument and subtegumental structures was seen. Tegumental alterations reached a peak 3 days after treatment and were characterized by swelling, fusion of distal cytoplasma, focal lysis of the tegumental matrix and vacuolisation. Tubercles and sensory organelles frequently degenerated or collapsed. Typical features of subtegumental alterations, including muscle fibres, syncytium and parenchyma tissues, were focal or extensive lysis, vacuolisation and degeneration of mitochondria. Severe alterations were also observed in gut epithelial cells and vitelline cells of female worms. Our findings of artemether-induced ultrastructural alterations in adult S. mansoni confirm previous results obtained with juvenile S. mansoni and S. japonicum of different ages.

Culex quinquefasciatus vitellogenesis: morphological and biochemical aspects

The vitellogenic process in Culex quinquefasciatus, which is triggered by a blood meal, involves the synthesis, distribution and storage of the nutrients necessary for embryo development. The fat body of an adult female Cx. quinquefasciatus revealed two cell types: large trophocytes and small, eosinophilic, "oenocyte-like" cells, which show no morphological changes throughout the gonotrophic cycle. Trophocytes, which only begin to synthesise vitellogenin (Vg) 12 h post-blood meal (PBM), undergo a series of morphological changes following engorgement. These changes include the expansion of the rough endoplasmic reticulum (RER) and Golgi complex, which are later destroyed by autophagosomes. At 84 h PBM, trophocytes return to their pre-engorgement morphology. The ovarian follicles of non-blood-fed Cx. quinquefasciatus contain a cluster of eight undifferentiated cells surrounded by follicular epithelium. After engorgement, the oocyte membrane facing the perioocytic space increases its absorptive surface by microvilli development; large amounts of Vg and lipids are stored between 24 and 48 h PBM. Along with yolk storage in the oocyte, follicular cells exhibit the development of RER cisternae and electron-dense granules begin to fill the perioocytic space, possibly giving rise to endochorion. Later in the gonotrophic cycle, electron-dense vesicles, which are possible exochorion precursors, fuse at the apical membrane of follicular cells. This fusion is followed by follicular cell degeneration.

The effect of sub-lethal doses of Azadirachta indica (Meliaceae) oil on the midgut of Spodoptera frugiperda (Lepidoptera, Noctuidae)

The fall armyworm, Spodoptera frugiperda, is one of the major field pests for maize production. It is mainly controlled by means of synthetic, and more recently by resistant cultivar of maize expressing Bt toxins. The neem tree, Azadirachta indica, is a plant that can potentially control insects with the advantage of being food and environmental safe. The aim of this study was to assess the effect of neem oil on the development and survival of S. frugiperda caterpillars by assessing histological alterations caused on their midgut. Newly hatched caterpillars were submitted to three neem oil concentrations: 0.006; 0.05; 0.4%, which were added to their artificial diet. Ten 3rd instar caterpillars, taken from each treatment, were submitted to histological analysis. The alimentary canals from the specimens were fixed in Baker for 12 hours, desiccated and diaphanized in alcohol/xylol (1:1) and xylol. After placing the samples in paraffin, they were sliced in 8 µm sections and stained with hematoxylin-eosin stain. The neem oil added to the diet of S. frugiperda caused total mortality at dose of 0.4% whilst still in the first instars, prolonged the larval and pupal stages, and reduced the pupal weight. Histo-physiological alterations such as degeneration of the epithelial lining of the midgut and in the peritrophic matrix were found at all concentrations of neem oil.

Recovery of degraded pasture in Rondônia: macronutrients and productivity of brachiaria brizantha

Pasture is the main form of land use in Amazonia. Over time the pasture grass loses vigor and yields decrease, indicating a certain degree of degeneration. The main causes of degradation are lack of pasture maintenance and subsequent weed infestation, the choice of regionally unsuitable forage species and excessive grazing. The main purpose of this study was to evaluate the impact of different recovery managements on soil chemical properties and grass yield of a degraded pasture in Rondônia. For this purpose, an experiment was installed in October 2001, consisting of five treatments: C = control; HA = harrowing + NPK + micronutrients; HE = Herbicide + NK + micronutrients; R = No-tillage rice + NPK + micronutrients; and S = No-tillage soybean + PK + micronutrients. The following N, P and K sources were used: ammonium sulfate for N, calcined phosphate for P and potassium chloride for K. The experiment was arranged in a randomized block design with four replications. The shoot dry matter yield of the grass was analyzed as of the 35th month of experimentation, in a dry and a rainy period. Phosphorus fertilization resulted in significant increases in Ca2+ and Mg2+ and increasing trend of P in the topsoil in the initial months of the experiment in treatments HA and S and increases in Ca2+ and P (trend) in the treatment R. The cumulative production of Brachiaria brizantha, from Sep/2004 to Mar/2005, was 30,025, 28,267 and 27,735 kg ha-1 shoot dry matter in the treatments HA, R and S, respectively. These values differed significantly from treatments C and HE, with 17,040 and 17,057 kg ha-1, respectively. It was concluded that phosphorus fertilization associated to pasture reform was effective to raise the dry matter yield of Brachiaria brizantha. Rice or soybean under no-tillage is recommended as a practice of pasture recovery, due to the residual effect of fertilization.

Apple biological and physiological disorders in the orchard and in postharvest according to production system

The study aimed to evaluate the incidence of biological and physiological disorders in the field and postharvested apples cvs. Gala, Fuji and Catarina grown in four production systems: conventional, organic transition, integrated and organic. Apples were evaluated for damages related to biological and physiological disorders in the orchard and after harvest. The greatest damages were attributed to pests, especially Anastrepha fraterculus in the organic system and Grapholita molesta in the organic transition. Apples produced in organic orchards had higher damage levels caused by postharvest physiological disorders than those grown in other production systems. For apples becoming from organic orchards most of the damage was due to lenticels breakdown and degeneration ('Gala'), and bitter pit ('Fuji' and 'Catarina'). The incidence of postharvest rot was not influenced by apple production system.

Compressive neuropathy of the first branch of the lateral plantar nerve: a study by magnetic resonance imaging

Abstract Objective: To assess the prevalence of isolated findings of abnormalities leading to entrapment of the lateral plantar nerve and respective branches in patients complaining of chronic heel pain, whose magnetic resonance imaging exams have showed complete selective fatty atrophy of the abductor digiti quinti muscle. Materials and Methods: Retrospective, analytical, and cross-sectional study. The authors selected magnetic resonance imaging of hindfoot of 90 patients with grade IV abductor digiti quinti muscle atrophy according to Goutallier and Bernageau classification. Patients presenting with minor degrees of fatty muscle degeneration (below grade IV) and those who had been operated on for nerve decompression were excluded. Results: A female prevalence (78.8%) was observed, and a strong correlation was found between fatty muscle atrophy and plantar fasciitis in 21.2%, and ankle varices, in 16.8% of the patients. Conclusion: Fatty atrophy of the abductor digiti quinti muscle is strongly associated with neuropathic alterations of the first branch of the lateral plantar nerve. The present study showed a significant association between plantar fasciitis and ankle varices with grade IV atrophy of the abductor digiti quinti muscle.

Carotenoids production: microorganisms as source of natural dyes

Carotenoids are natural dyes synthesized by plants, algae and microorganisms. Application in many sectors can be found, as food dyeing and supplementation, pharmaceuticals, cosmetics and animal feed. Recent investigations have shown their ability to reduce the risks for many degenerative diseases like cancer, heart diseases, cataract and macular degeneration. An advantage of microbial carotenoids is the fact that the cultivation in controlled conditions is not dependent of climate, season or soil composition. In this review the advances in bio-production of carotenoids are presented, discussing the main factors that influence the microbial production of these dyes in different systems.

Fármacos multifuncionais: monoamina oxidase e α-sinucleína como alvos terapêuticos na doença de Parkinson

Parkinson's disease (PD) is a neurodegenerative disorder associated to selective degeneration of dopaminergic neurons caused by an intricate relationship among dopamine metabolism, oxidative stress and α-synuclein fibrillation. Most therapies for PD have focused on dopamine replacement through the use of both monoamine oxidase inhibitors (MAOIs) and dopamine precursor L-dopa. Interestingly, certain MAOIs have a broad spectrum of action including anti-fibrillogenic properties in α-synuclein aggregation. Herein we revisit the chemical properties of MAOIs and their action on important targets associated with PD, notably α-synuclein fibrillation and dopamine metabolism, discussing the strategies associated with the development of multi-target drugs for neurodegenerative diseases.

Hamartoma cístico retrorretal

A 32-year-old woman was referred to our institution for a pelvic mass. She was asymptomatic and was found to have a mass on rectal examination. Magnetic resonance showed a large solid-cystic mass and the patient underwent complete surgical excision with pathologic findings suggesting retrorectal cyst-hamartoma. Tailgut cysts (or retrorectal cystic hamartomas) are rare congenital lesions settled in the retrorectal (presacral) space. They are made up of cysts lined by multiple types of epithelium, often predominantly mucin-secreting. The lesion requires complete surgical excision to prevent complications of recurrence, infection or carcinomatous degeneration.

Doença de Wilson e Gravidez: Relato de Caso

A doença de Wilson (degeneração hepatolenticular) é distúrbio autossômico recessivo raro que usualmente ocorre entre a primeira e terceira décadas de vida. Caracteriza-se por depósito excessivo de cobre no fígado e cérebro e é fatal se não diagnosticada e tratada precocemente. Os autores descrevem um caso de gravidez e doença de Wilson, mostrando a evolução satisfatória de uma paciente que fez uso da D-penicilamina até a sétima semana de gestação, quando a suspendeu por conta própria, e após a vigésima semana gestacional. A mãe evoluiu sem sinais de descompensação clínica ou obstétrica. O recém-nascido não apresentou nenhuma intercorrência e encontrava-se bem no final do primeiro ano de vida.

Effects of hyperprolactinemia and ovariectomy on the tibial epiphyseal growth plate and bone formation in mice

PURPOSE: To evaluate the effects of ovariectomy and the hyperprolactinemia procedure in the tibial epiphyseal growth plate of female mice.METHODS: In this study, the epiphyseal growth plate of ovariectomized (OVX) and/or rendered hyperprolactinemic female mice by 50 days of treatment with 200 μg metoclopramide (M) was evaluated morphologically, morphometrically and immuno-histochemically. Forty female and adult mice were divided into four groups according to treatment: V group - animals treated with saline solution; H group - hyperprolactinemic animals; Ovx/V group - ovariectomized animals and treated with saline solution; Ovx/H group - hyperprolactinemic and ovariectomized animals. After the treatment period, the animals were sacrificed, tibia was removed and fixed in 10% buffered formalin and decalcified in 10% formic acid. The material was immersed in paraffin and subjected to histological processing in paraffin. The sections were stained with Masson's trichrome and immunohistochemistry was carried out for the pro-apoptotic protein BCL-2. The images for the morphological and morphometric study were analyzed with the imaging program AxioVision 4.8 (Carl-Zeiss(r), Germany).RESULTS: The combination of hyperprolactinemia and the ovariectomy procedure decreased the number of resting chondrocytes 1.5-fold, the number of proliferative chondrocytes 1.8-fold; the percentage of resting cartilage 2.4-fold and the percentage of trabecular bone 2.1-fold, compared with respective control animals.CONCLUSION: The procedure of ovariectomy combined with the metoclopramide-induced hyperprolactinemia in female mice has showed marked bone degeneration due to significant decrease of cell proliferation in the epiphyseal growth plate and bone formation.

Histological changes caused by experimental Riedeliella graciliflora (Leg. Papilionoideae) poisoning in cattle and laboratory animals

Tissues from cattle, mice, rats and guinea pigs experimentally intoxicated by Riedeliella graciliflora were studied histologically. Cattle lymph nodes, spleen, Peyer patches and peribronchial lymphoid tissues had diffuse necrosis of lymphocytes, mainly in the germinal centers of the follicles. This lesion was less severe in laboratory animals. All species had severe enteritis with infiltration of the lamina propria by mononuclear cells. Some cells in this infiltrate were necrotic. Degeneration and necrosis of the epithelial cells, mainly in the tip of the villi, and detachment of the epithelial lining from the lamina propria were also observed. In the liver the trabecular structure was disrupted and the hepatocytes had some degree of individual necrosis and degeneration. A tubular nephrosis was observed in the kidneys. Liver, lung, kidney, intestine and lymph nodes had different degrees of congestion. Those lesions are similar than those caused by Polygala klotzschii, a plant that contains 5-metoxi-podophyllotoxin.

Experimental intoxication by the leaves of Melia azedarach (Meliaceae) in cattle

Green leaves of Melia azedarach were administered at single doses ranging from 5 to 30 g/kg bw to 11 calves. Clinical signs were depression, ruminal stasis, dry feces with blood, ataxia, muscle tremors, sternal recumbency, hypothermia and abdominal pain. Serum AST and CPK were increased. Signs appeared from 8 to 24 hours after dosing, and the clinical course lasted from 2 to 72 hours. Three calves dosed with 30g/kg bw died. The macroscopic findings included intestinal congestion, yellow discoloration of the liver, brain congestion and dry feces with blood in the rectum. The liver showed swollen and vacuolated hepatocytes. Necrotic hepatocytes were scattered throughout the parenchyma or concentrated in the periacinar zone. Degenerative and necrotic changes were observed in the epithelium of the forestomachs. There was also necrosis of the lymphoid tissue. Skeletal muscles showed hyaline degeneration and fiber necrosis. The necrotic fragments contained floccular or granular debris with infiltration by macrophages and satellite cells.

Crystal-associated cholangiopathy in sheep grazing Brachiaria decumbens containing the saponin protodioscin

An outbreak of hepatogenous photosensitization is reported in a flock of 28 sheep grazing Brachiaria decumbens in Mato Grosso do Sul State, Central-Western Brazil. Seven lambs and an adult sheep were affected and 6 of them died. Two surviving affected lambs and one lamb without clinical signs had increased serum values of gamma glutamyltransferase, bilirubin, and cholesterol. In two adult unaffected sheep those parameters were within normal values. An adult sheep submitted to necropsy presented moderate body condition, unilateral corneal opacity, drying of the muzzle, moderate jaundice, increased lobular pattern of the liver, and a distended gallbladder. Histological lesions were epithelial degeneration, necrosis, and hyperplasia of small bile ducts. Mild amounts of foamy macrophages were observed, mainly in the centroacinar zone. Diffuse swelling and vacuolation were observed in hepatocytes. Crystal negative images were found within bile ducts, foamy macrophages, and the lumen of some renal tubules. The heart showed multifocal areas of degeneration and necrosis of the muscle fibers. Pasture samples (Brachiaria decumbens) contained 2.36% of protodioscin. No Pithomyces chartarum spores were found in the pasture. Samples from a similar neighboring B. decumbens pasture grazed by cattle without photosensitization contained 1.63% of protodioscin isomers. Outbreaks of photosensitization caused by Brachiaria spp. are common in cattle in the Brazilian Cerrado (savanna) with about 51 million hectares of Brachiaria spp pastures. Sheep farming has been recently developed in this region, and the number of sheep is increasing significantly. Because sheep are more susceptible than cattle to lithogenic saponins, poisoning by Brachiaria should be an important limiting factor for the sheep industry.