Oxidative stress response system in Escherichia coli arising from diphenyl ditelluride (PhTe)2 exposure.

The toxicity of diphenyl ditelluride (PhTe)2 is associated with its ability to oxidize sulfhydryl groups from biological molecules. Therefore, we evaluated possible molecular mechanisms of toxicity induced by this organochalcogen in Escherichia coli (E. coli) by evaluating oxidative damage markers, relative expression of genes associated with the cellular redox state in bacteria, such as katG, sodA, sodB, soxS, and oxyR, as well as the activity of enzymes responsible for cellular redox balance. After exposure of (PhTe)2 (6, 12, and 24 µg/mL), there was a decrease in non-protein thiols (NPSH) levels, an increase in protein carbonylation and lipid peroxidation in E. coli. Intra- and extracellular reactive species (RS) was increased at concentrations of 6, 12, and 24 µg/mL. The superoxide dismutase (SOD) activity was increased at the three concentrations tested, while catalase (CAT) activity was higher at 12 and 24 µg/mL. The soxS gene showed lower expression at the three concentrations tested, while the oxyR gene was supressed at 24 µg/mL. The katG antioxidant response gene showed lower expression, and sodA and sodB were positively activated, except for sodB at 6 µg/mL. Our findings demonstrate that exposure to (PhTe)2 induced RS formation, NPSH depletion and changes in transcriptional factors regulation, characterizing it as a multi-target compound, causing disruption in cellular oxidative state, as well as molecular mechanisms associated in E. coli.

Myenteric neuroprotective role of aspirin in acute and chronic experimental infections with Trypanosoma cruzi.

BACKGROUND: Experimental and clinical studies have shown that myenteric neuron cell death during infection with Trypanosoma cruzi mainly occurs in the esophagus and colon, resulting in megaesophagus and megacolon, respectively. Evidence suggests that the cyclooxygenase enzyme (COX) is involved in the T. cruzi invasion process. The use of low-dose aspirin (ASA), a COX-1/COX-2 inhibitor, has been shown to reduce infection with T. cruzi. Therefore, in this study, we evaluated the effects of treatment with low-dose ASA on myenteric colonic neurons during murine infection with T. cruzi. METHODS: Swiss mice were assigned into groups treated with either phosphate-buffered saline or low doses of ASA during the acute phase (20 mg/kg ASA) and chronic phase (50 mg/kg ASA) of infection with the Y strain of T. cruzi. Seventy-five days after infection, colon samples were collected to quantify inflammatory foci in histological sections and also general (myosin-V+ ), nitrergic, and VIPergic myenteric neurons in whole mounts. Gastrointestinal transit time was also measured. KEY RESULTS: Aspirin treatment during the acute phase of infection reduced parasitemia (P<.05). Aspirin treatment during the acute or chronic phase of the infection reduced the intensity of inflammatory foci in the colon, protected myenteric neurons from cell death and plastic changes, and recovered the gastrointestinal transit of mice infected with T. cruzi (P<.05). CONCLUSION & INFERENCES: Early and delayed treatment with low-dose ASA can reduce the morphofunctional damage of colonic myenteric neurons caused by murine T. cruzi infection.

Sildenafil (Viagra®) blocks inflammatory injury in LPS-induced mouse abortion: A potential prophylactic treatment against acute pregnancy loss?

INTRODUCTION: Recurrent pregnancy losses (RPL) are common women's health issues. Inflammatory and thrombotic events have been associated with RPL including excessive production of cytokines, in particular TNF-α. However, mechanisms behind gestational losses are not yet fully understood. Sildenafil inhibits phosphodiesterase Type-5 (PDE5). This drug increases intracellular cyclic guanosine monophosphate, having vasodilatory and, more recently described, anti-inflammatory properties. PDE5 is present in murine and human uterus and placenta. Sildenafil is already used clinically for treatment of human fetal growth restriction (FGR). Our objective was to determine if Sildenafil alone or in combination with Heparin had protective effects in pregnant Swiss albino challenged to abort by lipopolysaccharide (LPS). METHODS: Treatments (Sildenafil (50 mg/kg/day), Heparin (500 IU/Kg/day) or Sildenafil + Heparin at the same doses) were initiated the morning of copulation plug detection (gestational day (gd0)). On the 15th day of pregnancy, an intra-peritoneal injection of LPS (100 µg/kg) was administered. Untreated, pregnant mice challenged by LPS served as controls. RESULTS: Assessments at 48 h after LPS revealed that Sildenafil + Heparin prevented fetal loss. Early assessments at 2 h after LPS indicated that the pretreatments prevented induction of inflammatory cytokine production (TNF-α, IL-1ß/NF-κß) and preserved placental histopathology. DISCUSSION: Combined Sildenafil + Heparin therapy was superior to either treatment alone in most analyses. The known safety of Sildenafil and Heparin in human pregnancy suggests that usage of these combined agents may be of value for treatment of patients with impending pregnancy loss or prophylactically in women with a history of recurrent miscarriages.

Risk factors associated with toxoplasmosis and toxocariasis in populations of children from nine cities in southern Brazil.

This study investigated the epidemiological factors that contribute to the seroprevalence of Toxoplasma gondii and Toxocara spp. in children from Paraná state, Brazil. Immunoglobulin G (IgG) antibodies to T. gondii were detected using indirect immunofluorescence, and IgG antibodies to Toxocara were detected using an enzyme-linked immunosorbent assay. For each individual, a questionnaire was completed that contained epidemiological and clinical data. The data analysis was performed using multiple logistic regression. Of the 544 children investigated, 3.2% presented co-infection with T. gondii and Toxocara spp. Of this total, 7.4% were positive for antibodies to T. gondii, and 25% were positive for antibodies to Toxocara spp. The presence of antibodies to Toxocara spp. increased the risk of T. gondii infection (P = 0.029). Children who were 1-8 years of age were less infected by T. gondii than those who were 9-12 years of age. The variables that influenced positivity for anti-Toxocara spp. were the origin of the children and contact with sand. Children with positive serology for Toxocara spp. presented more eosinophilia compared with those with non-reactive serology. Infection with both parasites reveals the need for preventive measures, such as guidance about modes of infection, parasite control and monitoring recreational areas.

Parameters for evaluation of clinical trial in mice infected with Trypanosoma cruzi / Parâmetros para avaliação clínica de camundongos infectados pelo Trypanosoma cruzi em experimentação

The effectiveness of clinical parameters in the evaluation of Trypanosoma cruzi infection was analyzed in male Swiss mice at 8 weeks old Animals were divided into HG (healthy) and IG (1400 trypomastigotes, intraperitoneally, Y strain - Trypanosoma cruzi). Quantitative and qualitative parameters were evaluated in non-consecutive days in the period, from 7th-11th and 15th-18th days of infection. There were significant differences (P<0.05) between both groups in both periods regarding water consumption, abdominal circumference and weight. The second group presented differences in amount of excreta, body temperature, move-up and mortality. There was no difference (P>0.05) between the groups in food consumption, exploration of self-cleaning and skin staining. The fecal feature differed between the groups in the second period. The occurrence of isolation was not practical. Differences were observed in the hair between groups, although the parameter had been interfered by fights between animals. The consumption of water, feed, excreta production, characteristic of the faeces, body temperature, abdominal circumference, move up, weight and mortality parameters are easy to be measured and effective in clinical differentiation of healthy mice infected with T. cruzi, elected in protocols for clinical study with mice, which is the first work to gather information of qualitative and quantitative clinical parameters evaluated in these animals.

Analisou-se a eficiência de parâmetros clínicos na avaliação da infecção pelo Trypanosoma cruzi em camundongos suíços, machos de 8 semanas. Os grupos foram divididos em GS (sadios) e GI (1400 tripomastigotas, intraperitoneal, cepa Y - Trypanosoma cruzi). Avaliaram-se parâmetros quantitativos e qualitativos em dias não consecutivos nos períodos, 7º-11º e 15º-18º dias de infecção. Observaram-se diferenças (P<0.05) significativas entre os grupos, nos dois períodos: consumo de água, circunferência abdominal e peso; apenas no segundo período: quantidade de excretas, temperatura corporal, movimento-levantar e mortalidade. Não houve diferença (P>0.05) entre os grupos: consumo de ração, exploração de auto-limpeza e coloração da pele. As fezes diferiram entre os grupos no segundo período. A ocorrência de isolamento não se mostrou prática. Diferenças no pêlo foram observadas entre os grupos, embora o parâmetro sofra interferência de brigas entre os animais. O consumo de água, ração, produção de excretas, característica das fezes, temperatura corporal, circunferência abdominal, movimento-levantar, peso e mortalidade são parâmetros fáceis de serem medidos e eficientes na diferenciação da clínica de camundongos sadios e infectados pelo T. cruzi, eleitos para protocolos de estudos clínicos com camundongos, sendo este o primeiro trabalho a reunir informações de parâmetros clínicos qualitativos e quantitativos avaliados nesses animais.

Leptospirosis-associated acute kidney injury: penicillin at the late stage is still controversial.

WHAT IS KNOWN AND OBJECTIVE: Some antimicrobial agents are active in vitro against Leptospiras. The use of penicillins at the late stage of leptospirosis is still controversial. We aimed to evaluate the use of penicillin in patients with leptospirosis-associated acute kidney injury (AKI). METHODS: A retrospective study was conducted of patients with leptospirosis admitted to two hospitals in Fortaleza city, Brazil, between 1985 and 2008. AKI was defined according to the RIFLE and AKIN classifications. Patients were divided in two groups according to whether they were treated with a penicillin or not. RESULTS: Two hundred and eighty-seven patients were included, with an average age of 36·8±15·6 years and mostly male (80·8%). One hundred and twelve patients (39%) received a penicillin. Patients treated with a penicillin were younger (32±14 years vs. 39±16 years, P=0·0002) and had a shorter hospital stay (8·4±5·0 vs. 11±7·7 days, P<0·0001). There was no difference in the onset of symptoms before hospital admission between the two groups (6·5±3·0 vs. 7·7±4·7, P=0·33). Systolic blood pressure was lower in the penicillin group (111±21 vs. 119±22 mmHg, P=0·04). AKI, need of dialysis and renal recovery at the time of hospital discharge were more frequent in patients who did not use a penicillin (P<0·05). Mortality was similar in both groups (11·6% vs. 13·7%, P=0·60). CONCLUSION: Treatment of leptospirosis with antibiotics, including the penicillin, remains controversial. The main benefit of using penicillin in the present study was a reduction in the length of hospital stay and fewer complications, such as AKI, but its use was not associated with a decrease in mortality. On balance of risks and benefits, we recommend the use of penicillin in late-stage leptospirosis.

Acute kidney injury in AIDS: frequency, RIFLE classification and outcome

The objective of the present study was to evaluate the characteristics of acute kidney injury (AKI) in AIDS patients and the value of RIFLE classification for predicting outcome. The study was conducted on AIDS patients admitted to an infectious diseases hospital inBrazil. The patients with AKI were classified according to the RIFLE classification: R (risk), I (injury), F (failure), L (loss), and E (end-stage renal disease). Univariate and multivariate analyses were used to evaluate the factors associated with AKI. A total of 532 patients with a mean age of 35 ± 8.5 years were included in this study. AKI was observed in 37 percent of the cases. Patients were classified as "R" (18 percent), "I" (7.7 percent) and "F" (11 percent). Independent risk factors for AKI were thrombocytopenia (OR = 2.9, 95 percentCI = 1.5-5.6, P < 0.001) and elevation of aspartate aminotransferase (AST) (OR = 3.5, 95 percentCI = 1.8-6.6, P < 0.001). General mortality was 25.7 percent and was higher among patients with AKI (40.2 vs17 percent, P < 0.001). AKI was associated with death and mortality increased according to RIFLE classification - "R" (OR 2.4), "I" (OR 3.0) and "F" (OR 5.1), P < 0.001. AKI is a frequent complication in AIDS patients, which is associated with increased mortality. RIFLE classification is an important indicator of poor outcome for AIDS patients.

Acute kidney injury in AIDS: frequency, RIFLE classification and outcome.

The objective of the present study was to evaluate the characteristics of acute kidney injury (AKI) in AIDS patients and the value of RIFLE classification for predicting outcome. The study was conducted on AIDS patients admitted to an infectious diseases hospital inBrazil. The patients with AKI were classified according to the RIFLE classification: R (risk), I (injury), F (failure), L (loss), and E (end-stage renal disease). Univariate and multivariate analyses were used to evaluate the factors associated with AKI. A total of 532 patients with a mean age of 35 ± 8.5 years were included in this study. AKI was observed in 37% of the cases. Patients were classified as "R" (18%), "I" (7.7%) and "F" (11%). Independent risk factors for AKI were thrombocytopenia (OR = 2.9, 95%CI = 1.5-5.6, P < 0.001) and elevation of aspartate aminotransferase (AST) (OR = 3.5, 95%CI = 1.8-6.6, P < 0.001). General mortality was 25.7% and was higher among patients with AKI (40.2 vs17%, P < 0.001). AKI was associated with death and mortality increased according to RIFLE classification - "R" (OR 2.4), "I" (OR 3.0) and "F" (OR 5.1), P < 0.001. AKI is a frequent complication in AIDS patients, which is associated with increased mortality. RIFLE classification is an important indicator of poor outcome for AIDS patients.

Frequência de parasitos intestinais em cães domiciliados da cidade de Maringá, PR / Frequency of intestinal parasites in domiciled dogs from Maringá city, Brazil

The frequency of eggs and cysts of intestinal parasites in domiciled dogs that lived in the city of Maringá, Brazil, was studied. From November 2006 to November 2007, stools of 81 dogs were examined, of which 44.4% were positive for some kind of enteric parasite. The most frequent was Ancylostoma spp. with 18.5% (15/81) followed by Giardia lamblia with 11.1% (9/81). There was association of parasites in 11.0% of the samples, being the most frequent Ancylostoma spp. and Trichuris vulpis (6.2%) (5/81). There were sources of contamination where the animals lived which were responsible for maintaining the parasite in the environment.

Cisticercose em animais abatidos em Sabáudia, Estado do Paraná / Cysticercosis in animals of Sabáudia, Paraná State

The aim of this work was to verify the occurrence of bovine and swine cysticercosis in animals slaughtered at the Abatedouro Municipal de Sabáudia, Paraná State. The number of daily-abated animals, the number of animals with cysticercus and the number and location of the cysticercus in the animals in a period of twelve months were collected. From 1046 swines slaughtered none showed cysticercus, but 36/out of 389 bovines (9.3 percent) were contaminated. Head was the most parasited region, followed by heart, tongue and liver. The absence of contamination observed in swines and the low contamination of the bovines reinforce the efficiency of the control measures accomplished in Paraná State.

Trypanosoma cruzi: sensitivity of the polymerase chain reaction for detecting the parasite in the blood of mice infected with different clonal genotypes.

The polymerase chain reaction showed high sensitivity for detecting Trypanosoma cruzi in the blood of mice, independent of clonal genotype (19, 20-T. cruzi I; 32, 39-T. cruzi II) or phase of the infection (acute or chronic).

Trypanosoma cruzi: two genetic groups in Paraná state, Southern Brazil.

This paper presents the genetic characterization of Trypanosoma cruzi strains isolated from chronic chagasic patients, triatomines, and sylvatic reservoirs from Paraná state, Southern Brazil, using the RAPD and SSR-PCR techniques. It has shown the presence of both phylogenetic groups of T. cruzi (I and II), describing for the first time the existence of T. cruzi II in Paraná state.

Genetic load caused by variation in the amount of rDNA in a wasp.

Extensive variation in the size of the short (heterochromatic) arm of chromosome 14 was found in the wasp Trypoxylon (Trypargilum) albitarse. Ten different variants were differentiated by size and C-banding pattern. Fluorescent in-situ hybridization (FISH) revealed that ribosomal DNA in this species is clustered in the darkly C-banded parts of the heterochromatic short arm of chromosome 14. On this basis, we got an indirect estimate of the amount of rDNA from the area of these dark C-bands. The significant absence in males of the three chromosome variants with lower amounts of rDNA indicates that these three variants are lethal in this sex, and suggests the existence of a threshold marking the minimum amount of rDNA which is tolerable in haploidy. This implies about 4% genetic load in the population caused by variation in rDNA amount.

Integration of a B chromosome into the A genome of a wasp, revisited.

A previous study showed that in the haplodiploid solitary wasp Trypoxylon albitarse, most individuals carry one B chromosome per haploid genome, the same dosage as the standard (A) chromosomes, indicating a possible regularization of B-chromosome meiotic behaviour and its integration into the A genome. In a new sampling, we have analysed 15 populations (including 9 out of the 10 previously analysed) to test the evolution of this integration process. The new results provide a direct report of the invasion process in the Porto Firme population, where B frequency has dramatically increased in only four generations. In the populations from the Viçosa region, however, B frequency has remained stable, although the principal B type, the metacentric one, has increased in frequency at the expense of the acrocentric one in several populations. The implications of these new results on the hypothesis of the integration of these B chromosomes, as regular members of the A genome, are discussed.

A leishmaniose tegumentar sob a perspectiva do paciente: resultado de uma prática educativa / Cutaneous leishmaniasis under the patient's perspective: an educational practice result

Foi realizado um estudo descritivo empregando a metodologia qualitativa entre portadores de leishmaniose tegumentar visando identificar a representatação que a doença tem para o seu portador, antes e depois do tratamento e intervenção educacional. O estudo foi realizado de setembro de 2000 a março de 2001 no Estado do Paraná, Brasil. Para a coleta dos dados foi realizada a entrevista semi-estruturada, sendo que os membros foram analisados pela técnica do discurso do sujeito coletivo. Foram destacadas as idéias centrais relacionadas com a etiologia da leishmaniose, sua transmissão/prevenção, gravidade, estigma, dificuldades do tratamento, sentimentos frente à doença e validade da educação em saúde.este estudo evidenciou que o acompanhamento dos pacientes e as medidas educacionais são de fundamental importãncia para que o grupo social assuma um maior controle sobre sua saúde, auxiliando sobremaneira no enfrentamento da doença e seu tratamento.

A descriptive study was carried out among cutaneous leishmaniasis patients using the qualitative methodology, aiming to identify the role that the disease has to its suffers both before and after treatment and educational intervention. The study was carried out from September 2000 to March 2001 in the state of Paraná, Brazil...

[Panstrongylus megistus in artificial ecotopes on islands of the Paraná River]. / Panstrongylus megistus em ecótopos artificiais de ilhas do Alto Rio Paraná

In response to complaints of triatomines on islands of the Alto Paraná River, an investigation to determine the presence of triatomines was conducted in 145 artificial ecotopes and 4 (2.8%) were infested, comprising a residence, a sports and leisure club, a former school and a woodpile. Of the 35 P. megistus collected, 17 were analyzed and 12 (70.6%) were found to be infected with Trypanosoma cruzi. Birds and rodents were the most common food sources. All serologic examinations (56 human, 18 dogs and 10 cats) were negative.

Secondary triatomine species in dwellings and other nearby structures in municipalities under epidemiological surveillance in the state of Paraná, Brazil.

OBJECTIVE: Since data are scarce regarding secondary triatomine species in the Brazilian state of Paraná, this study investigated infestations in inhabited and abandoned houses and in various other nearby structures in rural areas of that state. METHODS: Triatomines were manually captured in inhabited and uninhabited houses and other nearby structures in nine areas (eight municipalities and one district) of Paraná from June 1996 to February 2000. Testing for Trypanosoma cruzi infection was performed, as were also precipitin tests to determine the triatomines' food sources. RESULTS: While Triatoma infestans was not found in any of the nine areas of Paraná that were studied, three secondary triatomine species were detected: Triatoma sordida, Panstrongylus megistus, and Rhodnius neglectus. T. sordida was the most common species found, comprising 575 of the 658 triatomines captured (87.4%). The second-most common was P. megistus, with 82 specimens (12.5%). Of the various categories of structures investigated, uninhabited houses was the most frequently infested category (19/62, or 30.6%), followed by chicken coops (24/350, or 6.9%). The primary food source of the triatomines was the blood of birds. Nevertheless, in the municipality with the highest density of triatomines, the food sources included domestic animals and even humans. We found that 13.4% of the T. sordida and 13.5% of the P. megistus were infected with Trypanosoma cruzi. CONCLUSIONS: These results demonstrate the need to maintain entomological surveillance measures in the studied areas. This is especially important since Brazil and other countries of Latin America have affirmed the need to interrupt the vector-borne transmission of Chagas' disease.

Integration of a B chromosome into the A genome of a wasp.

B chromosomes are genome symbionts, the presence of which in many eukaryote species is explained, in most cases, by their violation of Mendelian rules, usually based on meiotic or mitotic instability, leading to their accumulation in the germ line (drive). However, B chromosome integration into the genome as a regular member of the chromosome set should imply the loss of drive. A possible way of bypassing this difficulty is to regularize meiosis when the B chromosome is frequent in the population, in order to yield gametes with one B chromosome. In diploid organisms, this task needs to be achieved in the two sexes, but in haplodiploids the problem simplifies to only the diploid sex. We have found, to the authors' knowledge, the first evidence of a B chromosome that is regularizing its meiotic behaviour and limiting its number to one B chromosome per haploid genome, the same dosage as the standard (A) chromosomes, in the solitary wasp Trypoxylon albitarse. It suggests a possible mechanism for B chromosome integration as a regular member of the chromosome complement.

The B chromosome system of Trypoxylon (Trypargilum) albitarse (Hymenoptera, Sphecidae) 1. Banding analysis.

Karyotypic analyses of 366 specimens of the solitary wasp Trypoxylon (Trypargilum) albitarse collected from ten populations in the municipalities of Viçosa and Porto Firme (Minas Gerais, Southeastern Brazil), revealed the presence of two morphological types of supernumerary (B) chromosomes. C-banding and fluorochrome banding suggest that the B chromosomes of T. albitarse may have originated from heterochromatin breaks within the standard (A) chromosome complement.

[The ACHEI Program: Chagas' disease awareness through comprehensive education in the municipality of Maringá, Northwest Paraná, Brazil]. / Programa ACHEI: Atenção ao chagásico com educaçao integral no município de Maringá e região noroeste do Paraná, Brasil.

This study analyzes 131 chagasic patients from different endemic areas that came to the Chagas' disease laboratory at the Maringa State University. The subjects discovered they were infected principally because they presented symptoms (58%) or donated blood (29.4%). During etiologic treatment for Trypanosoma cruzi, 45.2% of benznidazole users complained of side effects. Based on these data, the ACHEI program (Chagas' Disease Awareness through Comprehensive Education) was developed, which is a multiprofessional/interdisciplinary extension project. Monthly meetings are held that are divided into two parts: The first half of the meetings provide specific information, including the distribution of brochures explaining Chagas' disease transmission, symptoms and treatment. The second half of the meetings focuses on psycho-social assistance and includes topics such as self-esteem and personal responsibility. The meetings provide an environment for chagasic patients to share their concerns regarding post-diagnosis quality of life, fear, anxiety, stigma and family and social group relationships. In short, the meetings offer an opportunity for patients to reflect on their situation and to discover ways to deal with their disease.