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[en] We describe the evolution of parenchymal cerebral cysticerci on MRI, to assess signs of early cyst degeneration. We studied 15 lesions in four treated and one untreated patient. MRI was performed before therapy and repeated in the 1st month after each course of anticysticercus drugs, every 4 months during the 1st year and then annually; the follow-up period was 8-48 months. Lesions were classified according to changes in four features: cyst content and capsule signal, gadolinium enhancement and oedema signal. We were able to recognise each of the pathological phases; five MRI stages were identified. Stage 1 showed oedema and/or nodular gadolinium enhancement in the tissue invasion phase; stage 2 was cerebrospinal fluid-like signal within a cyst in the vesicular phase; stage 3 showed a thick capsule with an impure liquid content signal and surrounding oedema, in the cystic phase; stage 4 showed the disappearance of the cyst fluid content signal in the degenerative phase; stage 5 showed a calcified lesion in the residual phase. Stage 1 lesions disappeared after therapy; the other progressed from one stage to another. Stage 4 indicated the end of viability of the parasite and determined the point after which treatment was useless. On T2-weighted images changes in the cyst content differed according to the history of the lesion; nodular low intensity followed the natural degeneration of the parasite and a mixed fluid signal with punctate low signal seemed to represent the specific result of therapy. MRI staging can help in the evaluation of indications for treatment and facilitate clinical therapeutic trials. (orig.). With 4 figs., 1 tab
[en] Highlights: ► We confirm a previous report that infection with Leishmania can manifest multiple nodular lesions of the spleen. ► We confirm these lesions to be readily detectable with present imaging modalities. ► We affirm the fact that these lesions are hypoechoic on ultrasound, though in our case no hypoechoic halo was observed. ► We found these lesions to be hypodense on CT in the delayed phase after intravenous contrast administration. ► In addition to these previous findings we found that the spleen showed an inhomogeneous intensity on MRI; upon closer examination whilst scrolling through the T2-weighted sequences we can note multiple ill-defined and heterogeneous hypointense nodules. -- Abstract: We present a case of a 15-month-old Moroccan girl with fever of unknown origin, hepatosplenomegaly and multiple hypoechoic nodular splenic lesions that appear hypodense on CT. T2-weighted MRI sequences show a markedly inhomogeneous intensity of the parenchyma, seemingly caused by multiple ill-defined and heterogeneous hypointense nodules. Laboratory tests confirmed a recent infection with Leishmania, a parasite endemic to (sub)tropic regions. During and after therapy these lesions gradually resolved. To our knowledge this is the second published case in which different imaging modalities were able to demonstrate organ lesions associated with Leishmania. It is also the first report of MRI-findings associated with these lesions
[en] The effect of different sub sterilizing gamma ray doses on Sesame nonagrioides Lef., Lepidoptera Noctuidae is herein studies. It appears from the observed resultats that : - doses of 70 Gy are those required to obtain sub sterile insects. - F1 males from subterile parents present sterility superior to that of parents without any reduction in sexual competitivity on acouplement frequency. - On the 3 successive generations that we studies, the sex ratio is modified and a great residual sterility is observed.
[en] Leaf anatomy of Gaiadendron punctatum and Tripodanthus belmirensis species is described with the aim of exploring possible characters that allow a precise identification of these two genera, characterized by tree or shrub habit, belonging to Loranthaceae family. Samples were processed and stained with routine techniques for observation on optical microscope. Both species showed similarities, such as one-layered epidermis and rubiaceous type stomata. However, a different anatomic composition was observed in aspects such as: mesophyll, position and shape of epidermic cells and presence of suber accumulations in G. punctatum, or numerous idioblasts in T. belmirensis. A dichotomous key was constructed for species determination based on anatomical leaf characters, between the species of genus Tripodanthus and G. punctatum. Furthermore, the use of anatomical characters in determination and support of distinguishable taxonomical entities inside Loranthaceae is also briefly discussed.
[en] In this paper the use of radioisotope tracers in kinetic studies, problems associated with interpretation of kinetic data and graphical analysis of these data in parasitology are discussed
[en] The ability of Tocopherols deaerator Charon and Margabandhu, 1942 (Hymenoptera: Eulophidae) to search and parasitize Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) pupae in sugarcane stalks was evaluated. To analyze the ability for search and parasitism were used stalks of sugarcane (20 cm) where it was introduced a pupa of d. saccharalis (T1); a pupa and a caterpillar (T2) or a pupa and fecal matter (T3). Each stalk was placed in a transparent plastic bottle with 21 females of T. diatraeae. These pupae were isolated, after 72 h, in glass tubes at 25 +/- 2 Celsius degrade, 70 +/- 10 % relative humidity, and 14:10 light/dark. The experiment was developed in an entirely casualized design with three treatments and 12 repetitions. Percentage of D. saccharalis pupa parasitized by T. diatraeae was 50 %, 83.33 % and 16.66 % in the T1, T2 and T3, respectively (X"2 = 3.896, p"= 0.04). The presence of D. saccharalis caterpillars favored searching and parasitism of this host.
[en] Host specificity in the parasitic plant Cytinus hypocistis was quantified at four sites in the Algarve region of Portugal from 2002 to 2007. The parasite was found to be locally host specific, and only two hosts were consistently infected: Halimium halimifolium and Cistus monspeliensis. C. hypocistis did not infect hosts in proportion to their abundance; at three sites, 100% of parasites occurred on H. halimifolium which represented just 42.4%, 3% and 19.7% of potential hosts available, respectively. At the remaining site, where H. halimifolium was absent, 100% of parasites occurred on C. monspeliensis which represented 81.1% of potential hosts available. Other species of potential host were consistently uninfected irrespective of their abundance. Ecological niche divergence of host plants H. halimifolium and C. monspeliensis may isolate host-specific races of C. hypocistis, thereby potentially driving allopatric divergence in this parasitic plant.
[en] Skeletal hydatidosis results from the deposition of the larval form of the Echinococcus, a genus of tapeworm. The incidence of bone disease is extremely low as most larvae are trapped by the liver and lung upon release of the embryo into the portal blood stream. The interpretation of imaging studies can prove very confusing because bone changes evolve with time, and the non-specificity of these findings often leads to a mistaken diagnosis. We present the case of a 35-year-old woman with long-standing pain in the left hip joint in which the findings on CT were thought of as being either tuberculous or neoplastic in nature. The result of a CT-guided biopsy and another done following surgery concurred on an unexpected diagnosis of a hydatid cyst. This case illustrates that in the absence of a high index of suspicion for echinococcal infection, the semblance of imaging findings of hydatid disease in bone to those of other skeletal pathologies can lead to misinterpretation. Copyright (2002) Blackwell Science Pty Ltd
[en] Cysticercosis is a parasitic disease caused by a worm of the Cestoda class. The most prevalent form affects the nervous system. This case report is from a 78-year old female patient evaluated at Clinica Mult Imagem, in the city of Santos, Brazil, who presented a form of the disease that differed from the classic neurocysticercosis, in this case muscular cysticercosis. This and other forms of manifestation justify further studies to ensure adequate recognition, diagnosis and treatment of this parasitic disease. (author)
[en] A radiolabel uptake viability assay for Onchocerca cervicalis using [3H]2-deoxy-D-glucose in Hanks' balanced salt solution, pH 7.5, at 30 C is described and compared to the traditional visual motility assay. A correlation of r = 0.92 between the assays was found, with the radiolabel uptake method apparently a more sensitive indicator of microfilarial viability