Vlaudia Maria Assis Costa

Influence of neurotoxoplasmosis characteristics on real-time PCR sensitivity among AIDS patients in Brazil.

Cerebral toxoplasmosis among individuals with AIDS may be difficult to diagnose and needs to be differentiated from other neurological diseases. A validation study was performed on real-time PCR for detecting the B1 gene of Toxoplasma gondii in the blood and cerebrospinal fluid (CSF) of AIDS patients with cerebral toxoplasmosis. The study included 135 AIDS patients divided into two groups: Group I comprised 85 patients with neurotoxoplasmosis; and Group II comprised 50 patients with non-toxoplasmic neurological diseases. Real-time PCR on blood showed a sensitivity of 1.5%, specificity of 100.0%, positive predictive value (PPV) of 100.0% and negative predictive value (NPV) of 36.5%. CSF testing produced better results, with a sensitivity of 35.3%, specificity of 100.0%, PPV of 100.0% and NPV of 44.7%. The group presenting with pleocytosis and four or more encephalic lesions was associated with greater CSF positivity on PCR. In conclusion, real-time PCR on blood was not useful for diagnosis. CSF testing showed low sensitivity but high specificity. Greater numbers of lesions and greater CSF cellularity may improve the sensitivity of the method.

Discovery of Phthalimides as Immunomodulatory and Antitumor Drug Prototypes

Modulation of the immune system is an emerging concept in the control of tumor growth. While there are many mechanisms that underlie the role the immune system plays in tumor cells, minimizing metastasis by attenuating the expression of pro-angiogenic cytokines, or up-regulating the expression of endothelial factors that are crucial for the angiogenic process in metastasis and alternatively enhancing the antitumor immunity mediated by interferon-g and interleukin-2 are the most significant features identified to date. 3] In view of this, the discovery of small immunomodulating agents is a task that is currently receiving much attention. Among the anticancer and immunomodulatory drug candidates that have entered into clinical trials, the majority are analogues of thalidomide (Thl, 1), such as lenalidomide (Revlimid, CC-5013) and ACTIMID (CC-4047). Studies of structure–activity relationships (SARs) in the analogues and metabolites of Thl have shown that phthalimide is an essential pharmacophoric fragment. Following this line of research, phthalimide has commonly been employed in the design of potential anti-inflammatory, immunomodulatory, antiangiogenic, and antitumor drug candidates. Given this promising outlook, the strategy of molecular hybridization using phthalimide as a pharmacophoric fragment has figured prominently in recent research and has given rise to many successful outcomes. As an example, potent and selective histone deacetylase (HDAC) inhibitors have been designed by hybridizing two distinct structural domains: phthalimide and the hydroxamic acid subunit. This has led to the identification of various SARs and the discovery of a new potent hybrid lead compound, (E)-3-(1oxo-2-(1,2-diphenylethyl)isoindolin-6-yl)-N-hydroxyacrylamide, which has been described as having selective toxicity against tumor cells. On the other hand, the thiosemicarbazones have figured prominently in the vast number of structural subunits used to design anticancer agents. Some well-known mechanisms involving thiosemicarbazones involve the inhibition of ribonucleotide reductase, alteration of DNA structure, and the chelation of endogenous metals. An example of this versatility was recently reported by Gottesman and co-workers, who used the molecular hybridization of the b-isatin scaffold and thiosemicarbazones. It was clearly demonstrated that the insertion of a thiosemicarbazone subunit into optimal templates leads to an improvement in the anticancer properties of b-isatins, paving the way for the discovery of potent and selective anticancer compounds such as the lead compound 1-(5’-fluoroisatin)-4-(4’-methoxyphenyl)-3thiosemicarbazone (2 ; IC50 = 5.2 mm against multidrug-resistant cells that express P-glycoprotein). Because of this unique pharmacological profile, the attachment of thiosemicarbazones has been employed both in the design of ligands for further complexation with transition metals and during the processes of hit-to-lead or lead-todrug conversions. Bearing in mind the molecular pharmacophores outlined above and structural requirements, we describe herein the design, synthesis, and pharmacological evaluation of 11 new potential antitumor and immunomodulatory agents. To establish an appropriate set of SARs, we first prepared phthalimides containing the thiosemicarbazide 2 b or thiosemicarbazone 4 subunits. An attempt was then made to synthesize two bioisosteres of 2 b : the semicarbazide 2 a and aminoguanidine 2 c derivatives, in addition to the analogues of 2 b containing N-methyl or N-phenyl substituents. Subsequently, a short series of phthalimides bearing the thiazolin-4-one ring (compounds 3 a–d) was also investigated, for reasons of the bioisosteric relationship present between thiazolin-4-ones and thiosemicarbazones and the significant number of thiazolin-4-ones that are active against multidrug-resistant cancer cells, as in the case of the lead compound 3. Our design incorporated the molecular hybridization approach suggested by the structural features of prototypes 1–3 in addition to molecular bioisosterism (Figure 1). The compound series 2 a–f was first prepared by using microwave irradiation, in view of a recent report in which the reaction of N-(hydroxymethyl)phthalimide with arylamines using microwave heating under normal conditions rapidly furnishes [a] S. M. T. Cavalcanti, L. C. D. CoÞlho, Dr. M. Z. Hernandes, Prof. A. C. L. Leite, Dr. V. M. O. Souza Department of Pharmaceutical Sciences Centre for Health Science, Federal University of Pernambuco (UFPE) 50740-520 Recife, PE (Brazil) Fax: (+ 55) 081-2126-8510 E-mail : ana.leite@pq.cnpq.br [b] Dr. C. Pessoa, P. M. P. Ferreira, Dr. L. V. C. Lotufo, Prof. M. O. de Moraes Department of Physiology and Pharmacology Centre for Health Science, Federal University of Cear 60430-270 Fortaleza, CE (Brazil) [c] Dr. C. A. De Simone Department of Physics and Informatics Institute of Physics, University of S1⁄4o Paulo 13560-970 S1⁄4o Carlos, SP (Brazil) [d] Dr. V. M. A. Costa, Dr. V. M. O. Souza Laboratory of Immunopathology Keiso-Asami (LIKA) Department of Parasitology, UFPE 50740-520 Recife, PE (Brazil) Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/cmdc.200900525.

Influence of maternal schistosomiasis on the immunity of adult offspring mice

Schistosoma mansoni infection modulates the immunity to unrelated antigens in the host. In this study, we have investigated the effect of pregnancy and nursing from schistosomotic mother mice on the immune response to ovalbumin (OA), in adult offspring. Then, newborn mice were divided into four groups: animals born from infected mothers (BIM) suckled by non-infected mothers; animals from non-infected mothers suckled by infected mothers (SIM); and two other groups that were mice born and suckled in infected mothers (BSIM) or non-infected (control) mothers. The adult offspring were immunized with OA plus adjuvant. We compared the OA-specific hypersensitivity reactions (HR), antibodies levels (IgG, IgG2a) and the cytokine production in splenocyte cultures. Remarkable interleukin (IL)-10 synthesis was observed in mice BIM; while the anti-OA antibodies levels and immediate HR were impaired. IL-10 neutralization recovered this suppression. Differently, in mice SIM and BSIM there was an enhancement in the anti-OA humoral response and high IL-2 production, however low level of the IL-10 was detected in mice BSIM. In conclusion, schistosomotic pregnancy provides an immunosuppressive potential, IL-10 dependent, which was sustained throughout adult life. Regardless, suckling by infected mothers induces great responsiveness to an unrelated antigen and repairs the inhibitory potential acquired during prenatal stage.

Giardia lamblia e alergia respiratória: estudo em uma amostra de crianças de área urbana com frequência elevada da protozoose

OBJECTIVES: There is a high incidence of intestinal parasite infection in urban areas in the Northeast of Brazil. Giardia lamblia infections have been associated with increased prevalence of cutaneous allergies and gastrointestinal disorders. However, little is known about the relationship between giardiasis and allergic diseases of the airways. The present study aimed to investigate the possible association between respiratory allergic diseases and infections by G. lamblia in children from urban areas. METHODS: This study recruited 110 patients of both sexes aged 5-15 years. Patients were administered a questionnaire evaluating clinical symptoms and were given skin tests, parasite tests and serum tests. RESULTS: A high incidence of G. lamblia was observed (45%, 50/110). Infections by this protozoan were not associated with increased risk of respiratory allergy (p = 0.075), high total IgE levels (p = 0.701), positive specific IgE tests (p = 0.250), or positive skin tests for a range of environmental allergens (p = 0.239). CONCLUSION: This study demonstrated that symptoms of asthma, skin allergy and serum markers were not associated with G. lamblia infections in this sample of children from urban areas.OBJECTIVES There is a high incidence of intestinal parasite infection in urban areas in the Northeast of Brazil. Giardia lamblia infections have been associated with increased prevalence of cutaneous allergies and gastrointestinal disorders. However, little is known about the relationship between giardiasis and allergic diseases of the airways. The present study aimed to investigate the possible association between respiratory allergic diseases and infections by Giardia lamblia in children from urban areas. METHODS This study recruited 110 patients of both sexes aged 5-15 years. Patients were administered a questionnaire evaluating clinical symptoms and were given skin tests, parasite tests and serum tests. RESULTS A high incidence of Giardia lamblia was observed (45%, 50/110). Infections by this protozoan were not associated with increased risk of respiratory allergy (p = 0.075), high total IgE levels (p = 0.701), positive specific IgE tests (p = 0.250), or positive skin tests for a range of environmental allergens (p = 0.239). CONCLUSION This study demonstrated that symptoms of asthma, skin allergy and serum markers were not associated with Giardia lamblia infections in this sample of children from urban areas.

Ascaris lumbricoides infection in urban schoolchildren: Specific IgE and IL-10 production ,

BACKGROUND Helminth infections and allergies are diseases with intense Th2 lymphocytes participation and characterised by a high IgE and Interleukin-(IL) IL-4, IL-5 production and eosinophilia. However, helminths also induce IL-10 production, which may alter the outcome of allergic diseases in infected patients. OBJECTIVE This experimental study analyses the relationship between IL-10 production by cell culture from geohelminth infected and non-infected children and specific IgE to Ascaris lumbricoides (Asc) or Blomia tropicalis (BT). METHODS IL-10 content in supernatant from peripheral blood mononuclear cell culture from nine helminth infected and eleven non-infected patients was determined by ELISA after in vitro stimulation with Asc or BT extracts. RESULTS A positive association was observed between total IgE levels and anti-Ascaris and anti-Blomia tropicalis specific IgE, independent of infection status. For both helminth-infected and non-infected groups, there was no difference in IL-10 production in response to Asc extract, even though anti-Ascaris IgE levels were higher in the latter group. In response to BT stimulus, a lower production of IL-10 by the geohelminth-infected group was observed, but with no relationship between IL-10 production and specific IgE to BT. CONCLUSION The results suggest that anti-Ascaris IgE in non-infected patients may be associated to a resistance to parasites. Levels of specific IgE to parasite antigens or B. tropicalis allergen were not impaired by IL-10 production in children from an urban area in which geohelminthiasis is endemic.

Study of the Activity of 3-benzyl-5-(4-chloro-arylazo)-4-thioxo-imidazolidin-2-one against Schistosomiasis Mansoni in Mice

Previous studies conducted with the imidazolidinic derivative 3-benzyl-5-(4-chloro-arylazo)-4-thioxo-imidazolidin-2-one (LPSF-PT05) show outstanding activity against adult Schistosoma mansoni worms in vitro. In the first phase of this study, S. mansoni-infected mice were treated, orally, with 100 mg/Kg of the LPSF-PT05 in three formulations: Tween 80 and saline solution, oil/water (70 : 30) emulsion, and solid dispersion with polyethylene glycol (PEG). In the second phase, three other doses of the LPSF-PT05 in PEG were tested: 3, 10, 30 mg/kg. These treatment regimens significantly reduced the number of recovered worms due to increases in the solubility of the compound in this formulation; the greatest reduction (70.5%) was observed at the dose of 100 mg/kg. There was no changes in the pattern of mature egg compared to immature eggs; however there was a significant increase in the number of dead eggs. Histopathological analysis of liver tissue showed changes in morphological aspects of the hepatic parenchyma with decrease exudative-productive hepatic granuloma stages, although we found no significant differences in IFN-γ, IL-4, IL-10, or NO production in response to the specific antigen SEA. The results show the derivative LPSF-PT05 to be a potential candidate in the etiological treatment of schistosomiasis with a possible dampening effect of the granulomatous process.

Features to validate cerebral toxoplasmosis

INTRODUCTION Neurotoxoplasmosis (NT) sometimes manifests unusual characteristics. METHODS We analyzed 85 patients with NT and AIDS according to clinical, cerebrospinal fluid, cranial magnetic resonance, and polymerase chain reaction (PCR) characteristics. RESULTS In 8.5%, focal neurological deficits were absent and 16.4% had single cerebral lesions. Increased sensitivity of PCR for Toxoplasma gondii DNA in the central nervous system was associated with pleocytosis and presence of >4 encephalic lesions. CONCLUSIONS Patients with NT may present without focal neurological deficit and NT may occur with presence of a single cerebral lesion. Greater numbers of lesions and greater cellularity in cerebrospinal fluid improve the sensitivity of PCR to T gondii.

Cerebral toxoplasmosis: unusual MRI findings

BACKGROUND Single cerebral toxoplasmic lesions are rarely explored. METHODS Through magnetic resonance imaging, 10 lesions were analyzed regarding location, signal intensity, contrast enhancement, eccentric target, and meningeal uptake. RESULTS Five lesions were corticosubcortical and in the deep three (60%) had infratentorial locations. Iso- or hypointense signal predominated in T1 sequence, but in T2, there was variability. Perilesional edema and ring contrast enhancement occurred in 100% of lesions, but eccentric targets and meningeal uptake were less frequent. CONCLUSION Even in the presence of single lesions, iso- or hypointense signal in T1, perilesional edema, and ring enhancement are suggestive of cerebral toxoplasmosis.

Bone marrow-derived monocyte infusion improves hepatic fibrosis by decreasing osteopontin, TGF-β1, IL-13 and oxidative stress

AIM To evaluate the therapeutic effects of bone marrow-derived CD11b+CD14+ monocytes in a murine model of chronic liver damage. METHODS Chronic liver damage was induced in C57BL/6 mice by administration of carbon tetrachloride and ethanol for 6 mo. Bone marrow-derived monocytes isolated by immunomagnetic separation were used for therapy. The cell transplantation effects were evaluated by morphometry, biochemical assessment, immunohistochemistry and enzyme-linked immunosorbent assay. RESULTS CD11b+CD14+ monocyte therapy significantly reduced liver fibrosis and increased hepatic glutathione levels. Levels of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-6 and IL-1β, in addition to pro-fibrotic factors, such as IL-13, transforming growth factor-β1 and tissue inhibitor of metalloproteinase-1 also decreased, while IL-10 and matrix metalloproteinase-9 increased in the monocyte-treated group. CD11b+CD14+ monocyte transplantation caused significant changes in the hepatic expression of α-smooth muscle actin and osteopontin. CONCLUSION Monocyte therapy is capable of bringing about improvement of liver fibrosis by reducing oxidative stress and inflammation, as well as increasing anti-fibrogenic factors.

Maternal schistosomiasis alters costimulatory molecules expression in antigen-presenting cells from adult offspring mice ☆

Adult offspring of Schistosoma mansoni-infected mice showed alterations in immunity to a heterologous antigen, ovalbumin (OA). Prior breastfeeding induced increased production of anti-OA antibodies, while pregnancy impaired it. Here, we investigated the expression of costimulatory molecules on antigen-presenting cells (APCs) of the adult offspring of S. mansoni-infected mothers in response to OA. Newborn mice were divided into three groups: animals Born Infected Mothers (BIM) suckled by non-infected mothers; animals from non-infected mothers Suckled Infected Mothers (SIM); and another group of mice born from and suckled by non-infected mothers (CONTROL). The adult offspring were immunized with subcutaneous OA+adjuvant, and 3-8days following immunization, double labeling was performed (CD45R/B220 or CD11c and CD80, CD86, CD40 or HLA-DR) on spleen cells. In comparison to the CONTROL group, an early increased frequency of CD40+/CD80+ B cells was observed in SIM mice (p<0.001/p<0.05), but no alteration of CD11c+ cells was observed. In contrast, in BIM mice, the frequency of CD86+/CD11c+ cells (p<0.05) and CD40+/CD80+/CD86+ B cells (p<0.01/p<0.01/p<0.05) was drastically reduced. In conclusion, previous suckling by S. mansoni-infected mothers enabled improved antigen presentation by B cells in adult offspring, whereas gestation in these mothers imprinted offspring with weak antigen presentation by APCs during the immune response to a non-related antigen.