Boosting the suppressive effects of Ascaris suum components in IFN-γ-deficient mice

High molecular weight components from Ascaris suum extract suppress ovalbumin-specific immunity in mice. In IFN-γ-deficient mice, ovalbumin-specific delayed-type hypersensitivity reactions are more strongly downregulated by these suppressive components. Here, the cellularity of the delayed-type hypersensitivity reaction in IFN-γ-deficient mice and the increased downregulation induced by Ascaris suum components were analyzed. IL-12p40-dependent neutrophilic influx was predominant. Suboptimal doses of the suppressive fraction from this nematode completely inhibited the hypersensitivity reaction, thus indicating intensification of the immunosuppression under conditions of intense recruitment of IFN-γ-independent neutrophils.

Capillaria hepatica-induced septal fibrosis in rats: a contribution to the study of liver fibrogenesis

INTRODUCTION: Septal fibrosis of the liver regularly develops in rats infected with the nematode Capillaria hepatica. Curative treatment of the infection prevents the development of septal fibrosis when intervention occurs up to postinfection day (PID) 15, but not later. The present investigation aimed to demonstrate which parasitic factors are present when the process of septal fibrosis can no longer be prevented by curative treatment. METHODS: Wistar rats were infected with 600 embryonated eggs of C. hepatica administered by gavage and treated with ivermectin and mebendazole in separate groups at PIDs 10, 12, 15, 17 or 20. Rats from each group and their nontreated controls, were killed and examined 40 days after the end of treatment. RESULTS: Findings by PID 15 were compatible with the stage of complete maturation of infection, when worms and eggs were fully developed and a complex host-parasite multifocal necroinflammatory reaction showed greater intensity, but with no signs of septal fibrosis, which appeared from PID 17 onward. CONCLUSIONS: Since the worms spontaneously died by PID 15, not only septal fibrosis production, but also its maintenance and further development appeared dependent on the presence of eggs, which were the only parasitic factor remaining thereafter.

In vitro predatory activity of conidia of fungal isolates of the Duddingtonia flagrans on Angiostrongylus vasorum first-stage larvae

INTRODUCTION: Angiostrongylus vasorum is a nematode that parasitizes molluscs, dogs, and even man. METHODS: The objective was to evaluate the predatory activity of the conidia of two fungal isolates of Duddingtonia flagrans (AC001 and CG722) on first-stage larvae (L1) of A. vasorum in laboratory conditions. RESULTS: At the end of the experiment, there were significant reductions (p<0.01) of 74.5% and 63.2%, on average, in the A. vasorum L1 recovered in the AC001 and CG722 treatment conditions, respectively. CONCLUSIONS: The two isolates of fungi were efficient in the capture and destruction of A. vasorum L1.

Fulminant gastrointestinal hemorrhage due to Strongyloides stercoralis hyperinfection in an AIDS patient

Strongyloides stercoralis is an endemic nematode to tropical and subtropical regions of the globe. The parasite is capable of autoinfection, which is limited by an intact immune response. In immunocompromised hosts, hyperinfection and dissemination can occur and have a high index of mortality. A hyperinfection syndrome with dissemination is frequently associated with corticosteroid administration and other conditions (malignancies and organ transplantation). Interestingly, although strongyloidiasis is common among AIDS patients in endemic areas, the hyperinfection syndrome is rarely noted. We report here on a rare manifestation of fulminant gastrointestinal hemorrhage due to hyperinfection of strongyloidiasis in a female drug-abusing, alcoholic HIV/AIDS patient.

THE EFECTS OF SETTLEMENT ON THE PREVALENCE OF AscarisINFECTION IN TWO AMERINDIAN POPULATIONS OF THE BRAZILIAN AMAZON

Studies were made of the intestinal parasites of Amerindian populations of the Uaupes River basin of Brazil. Three groups were sampled: 1) Tukano fisher-agriculturalists who live in permanent riverine villages; 2) Maku hunter-horticulturalists who live in close contact with the Tukano fishing villages; and 3) Maku who inhabit the forest interior and have little contact with permanent settlements. Fecal samples were collected from 498 individuals of which 220 were from the first group, 135 from de second and 143 from the third. The samples were analyzed by means of microflotation and centrifugal sedimentation. A total of 18 protozoan and helminth species were recorded based on the presence of cysts or eggs. These included five nematode species that could not be identified. The three common pathogenic nematodes were found to be prevalent: the hookworm, Necator americanus(96%); the whipworm, Trichuris trichiura(77%) and the large roundworm, Ascaris lumbricoides(75%). The prevalence of Ascarisamong the villages was found to vary from 56 to 100%. Individuals living in, or associated with, permanent settlements had higher prevalence and intensity rates than those living in the nomadic hunter-gatherer way. This is shown to be directly related to fecal contamination of the environment in and around permanent settlements. The prevalence of Ascarisin a population can be used as an indicator of such environmental contamination.

In vitro studies of the anthelmintic activity of Picrolemma sprucei Hook. f. (Simaroubaceae)

1300 ppm (1.3 g / L), water and ethanol extracts prepared from stems or roots of Picrolemma sprucei Hook. f. were lethal (85-90 % mortality) in vitro to Haemonchus contortus (Barber Pole Worm) larvae, a gastrointestinal nematode parasite found in domestic and wild ruminants. Neosergeolide and isobrucein B were isolated in 0.0083 and 0.0070 % yield from dry, ground P. sprucei stems (0.89 kg). Neosergeolide, isobrucein B and the anthelmintic drug standard levamisole all caused comparable mortality rates (68-77 %) in vitro to H. contortus at similar concentrations (81-86 ppm). The anthelmintic activity of P. sprucei infusions (teas), alcohol extracts, and neosergeolide and isobrucein B, has therefore been demonstrated for the first time.

Caracterização química e granulométrica de solos do Golfão maranhense

A área de estudo corresponde aos campos flúvio-marinhos com risco de inundação e presença de solos hidromórficos da região do Golfão Maranhense. Os solos dessa região apresentam algum impedimento a drenagem, proximidade com o mar (fonte de sais), condições favoráveis a inundação e aos processos de evaporação. Este conjunto de fatores pode elevar as concentrações de sais solúveis e inviabilizar ou reduzir a produtividade. Foram coletadas 38 amostras de solo em 22 pontos com trado holandês a profundidades variáveis, normalmente de 0 a 20 e de 30 a 50 cm. As amostras foram secas ao ar e analisados atributos químicos e granulométricos. Os solos do golfão maranhense apresentam grande variabilidade e predominam os com argila de atividade alta, alta soma de bases e altos teores de hidrogênio e alumínio. Os teores de magnésio são predominantes em relação aos de cálcio. Apesar da maioria dos solos apresentarem textura argilosa a granulometria é bastante variável. Mesmo com altos teores de magnésio e de sódio o grau de floculação das amostras pode ser considerado alto. Os solos do Golfão Maranhense não se encontram salinizados, porém é necessário manejá-los de maneira adequada para não promover sua salinização.

Occurrence of Aelurostrongylus abstrusus (Railliet, 1898) larvae (Nematoda: Metastrongylidae) infecting Achatina (Lissachatina) fulica Bowdich, 1822 (Mollusca: Gastropoda) in the Amazon region

Achatina fulica or "giant African snail" is an exotic species, considered to be one of the world's hundred most invasive species, causing serious environmental damages. In the present study we report, for the first time, the occurrence of Aelurostrongylus abstrusus infecting A.fulica in the Amazon region. This nematode is described parasitizing mainly the pulmonary system of felines, which causes "aelurostrongilose", also known as feline cardio-pulmonary strongyloidosis. New morphometric data of third stage larvae are presented herein. The present study demonstrated that 40% of all the snails were infected by A. abstrusus. Achatina fulica specimens were collected from three different areas in Manaus namely: rural; east and west areas. The east area presents the highest prevalence of 80%. The large number of A.fulica found in inhabited areas increases the chances of emergent zoonoses, which highlights the need of further studies so as to better control this disease.

Endoparasite fauna of Brycon amazonicus and B. melanopterus(Characidae, Bryconinae) from Negro and Solimões rivers, Amazon, Brazil

ABSTRACTCongeneric host species present similar biological and behavioral aspects, what may favor the presence of a similar parasite fauna. The aim of the present study was to compare the composition and structure of the parasite community from congeneric species, Brycon amazonicus and B. melanopterus, collected on the Negro and Solimões Rivers. The fish internal organs were longitudinally opened and analyzed under stereomicroscope. The examination revealed that B. amazonicuswas parasitized by Procamallanus(Spirocamallanus) inopinatus(26.7% and 35.5%), Contracaecum type 2 (10% and 16.13%) and Rhabdochona acuminata(0% and 3.23%), prevalence values for Negro and Solimões River, respectively. The analysis of B. melanopterus, a fish species found only in the Solimões River, revealed P.(S.) inopinatus(33.3%), Contracaecum type 1 (60%) and R. acuminata(3.34%). These results indicate that the taxonomic proximity of the hosts was a stronger influence on the parasite species than external host environment.

Constatação da moléstia do «anel vermelho» do coqueiro no Estado do Rio de Janeiro. Redescrição do agente causador - Aphelenchoides cocophilus (Cobb, 1919) Goodey, 1933 (Nematoda, aphelenchidae)

As it is generally said, the red ring disease of coconut palm (Cocos nucifera L.) is caused by a nematode which is regularly found in the diseased tissues. Such a nematode was described by COBB in 1919 as Aphelenchus cocophilus, having been placed by GOODEY, in 1933, in the genus Aphelenchoides. The species has been found occurring in three States of this country (Alagoas, Sergipe and Bahia). However, the Authors received from the Instituto de Ecologia e Experimentação Agrícolas, in Rio de Janeiro, a few samples of coconut tissues badly infested. So, its area of distribution is considerably enlarged. A. cocophilus is so slender and delicate a form that descriptions based on preserved material are frequentely inadequate. Thus, the Authors took this opportunity to re-examine and redescribe the species, as it was suggested by GOODEY (1923), what had not previously been made by those brazilian workers who have dealt with the disease. The population studied generally agreed with those examined by COBB (1919) and GOODEY (1923) in the details given, except in the dimensions mainly of the tail, as it is shown in table 1, where the measurements of 5 females and 5 males are presented.

Experimentos com os nematicidas D. D., E. D. B. e brometo de metilo no combate aos nematódeos causadores de galhas em raízes de plantas (Meloidogyne spp.)

Tomato roots heavily disfigured by root-knot nematodes were throughly mixed with soil. At various time intervals, samples were taken from the mixture and treated in closed containers by each of the folio wing nematicides: D.D., E.D.B. and M.B. The efficacy of the treatment was tested by setting indicator plants in the treated soil and by examining their roots for the presence of galls two months later. In other words, the ability of the three nematicides to penetrate nematode galls after various periods of rotting, which varied from 5 to 30 days was studied. The main conclusions drawn are as follows: a) no nematicide among the three listed above showed the ability for complete destruction of the nematodes protected inside the roots, for a number of small galls developed on the root system of the indicator plant in all treatments; b) smaller and less numerous galls were present on the roots of the indicator plants grown in soil treated after a rotting period of 30 days; c) however, the control obtained seems to be quite satisfactory economically, since the check plants grew poorly and have developed a very unhealthy root system. This is in accordance with STARK & LEAR (1947), LEAR (1951) and CICCARONE's (1951) statements. The results of the present experiments show again that awaiting for the rotting of galls of the root-knot nematodes is not indispensable for an economically convenient soil fumigation. Fields in which many fleshy infected roots from previous crops have been buried can be economically fumigated immediately, without any loss of time. Notwithstanding, when thick woody roots are present in the soil, the above statements may not hold true. This should constitute a new problem calling for further experiments. Another essay dealing with methyl bromide alone, consisted in treating cotton roots heavily disfigured by Meloidogyne incognita in a container (diameter = 28cm, height = 32 cm), which remained closed for five days. After the treatment, the roots were mixed with soil, in which tomato seedlings were planted. After a growing period of two months, the roots of the tomato plants were washed in running water and examined for the presence of galls. As an early infeccion was present in the root system of all plants, the inefficacy of the treatment has been proved.

Nota sôbre o gênero Mononchus de nematódeos predadores

Seven species of the nematode genus Mononchus Bastian, 1865, were found in the State of São Paulo, Brazil. Such are: M. subsimilis Cobb, 1917; M. ibitiensis Carvalho, 1951; M. piracicabae Lordello, 1953; M. risoceiae Carvalho, 1955; M. soutoi Carvalho, 1956; M. coronatus Carvalho, 1956; and M. jairi n. sp. Outside the State, the following species have been found: M. papillatus (Bastian, 1865) Cobb, 1916; M. monhystera Cobb, 1917; M. muscorum (Dujardin, 1845) Cobb, 1916; M. gymnolaimus (Cobb, 1893) Cobb, 1916; M. consimilis Cobb, 1917; M. trichurus Cobb, 1917; M. reversus Cobb, 1917; and M. dentatus Cobb, 1917 (LORDELLO, 1953). This field of investigation has scarcely been touched and additional collections will doubtless add new forms to the number of species known as yet. M. jairi n. sp. most closely resembling species is M. monhystera Cobb, 1917, from which it differs in having: a) labial region more expanded, set off from neck by a broad shallow depression; b) anterior portion of the pharynx-wall rather thinner and directed outward; and, c) smaller dimensions (788.0-924.0: 1,100.0 micros).

(Nota n.º 3) Nematódeos da aboboreira

In the State of S. Paulo, Brazil, squash plants (Cucurbita spp.) are attacked by the Javanese nematode (Meloidogyne javanica) and by M. incognita acrita. Squash belongs to that group of plants in which the root-knot nematodes break through the root surface, so that the egg-producing females protrude from the root, showing yellowish or brow nish egg masses attached to them. Washed roots show numerous small dark spots, each corresponding to an ootheca, which is adhering to a mature female. A curious abnormal female of M. i. acrita was obtained from a sample of squash roots. This female's body showed two globular parts, separated by a deep constriction. The convoluted ovaries were found to fill both portions of the body.

Nematódeos e bactérias em fôlhas de alcachôfra

Diseased plants of artichoke (Cynara scolimus L.) from the Instituto Agronômico, Campinas, Brazil, harboured nematodes in the leaves. The nematodes proved to belong to the species Protorhabditis oxyuris (Claus, 1862) Dougherty, 1955. As it could not be charged as the primary agent of the disease, a study of the bacteria found in the material was made. This disclosed that 4 different bacterial forms were present, namely Bacillus subtilis, Bacterium udum, Xanthomonas beticola var. cynarae n. var., and Cory neb acterium fascians var. cynarae n. var. The typical forms of X. beticola and of C. fascians are known as pathogenic to a number of plants: but, in the present case, unfortunately no inoculation trial could be made as an attempt to clear up the possible pathogenicity of any of them also to Cynara scolimus. The nematode P. oxyuris is the secondary agent, which however possibly play an important part in the distribution of the bacteria, as it has been repeatedly pointed out by previous writers with reference to closely related species. The symptoms of the disease are described. The main injuries found on leaves were necrotic areas progressing from the distal part of the limb, resulting in a great reduction of the leaf superficies.

Ocorrência de endotoquia matricida em Meloidogyne javanica (Nematoda, Heteroderidae)

In the past years, several writers described eudotokia matricida in nematodes belonging to the family Rbabditidae. In 1958, LOOF dealt with two cases he observed in Apbeltncboides fragariae and Pratylencbus coffeae , showing that such phenomenon eventually occurs in the Tylencbida, families Apbelencboididae and Tylencbidae respectively. A third case referring to another tylenchid nematode is described in this paper, the species envolved having been identified as Meloidogyne javanica, of the family Heteroderidae.