ANTIGENIC RELATEDNESS OF SELECTED FLAVIVIRUSES: STUDY WITH HOMOLOGOUS AND HETEROLOGOUS IMMUNE MOUSE ASCITIC FLUIDS

The antigenic relationship of 9 flaviviruses, Yellow fever (YF) , Wesselsbron (WSL) , Uganda S (UGS) , Potiskum (POT), West Nile (WN) , Banzi (BAN) , Zika (ZK) , Dengue type 1 (DEN-1) and Dengue type 2 (DEN-2), was assessed by cross-haemagglutination-inhibition (Cross-HI) and cross-complement fixation (Cross-CF) reactions between each of the viruses and their homologous immune mouse ascitic fluids. Titre ratios were calculated using the heterologous and homologous titres. Cross-CF reactions revealed wider antigenic variations among viruses than Cross-HI reactions. There was no significant antigenic variation between WSL, POT and YF viruses using either of those methods. However, definite differences in antigenicity were observed between them and UGS, BAN and ZK viruses. There were no significant differences between UGS, BAN and ZK or between DEN-1 and DEN-2. The serological relationship among flaviviruses is important in establishing diagnosis and epidemiology of these infections in Africa.

Alternative solvents in carvone hydrogenation

Dissertação para obtenção do Grau de Mestre em Engenharia Química e Bioquimica

Sulphonamide-imprinted sol–gel materials as ionophores in potentiometric transduction

This work proposes different kind of solid-contact graphite-based electrodes for the selective determination of sulphonamides (SPHs) in pharmaceuticals, biological fluids and aquaculture waters. Sulfadiazine (SDZ) and sulfamethoxazole (SMX) were selected for this purpose for being the most representative compounds of this group. The template molecules were imprinted in sol–gel (ISG) and the resulting material was used as detecting element. This was made by employing it as either a sensing layer or an ionophore of PVC-based membranes and subsequent potentiometric transduction, a strategy never reported before. The corresponding non-imprinted sol–gel (NISG) membranes were used as blank. The effect of plasticizer and kind/charge of ionic lipophilic additive was also studied. The best performance in terms of slope, linearity ranges and signal reproducibility and repeatability was achieved by PVC membranes including a high dielectric constant plasticizer and 15 mg of ISG particles. The corresponding average slope was −51.4 and −52.4 mV/decade, linear responses were 9.0 × 10−6 and 1.7 × 10−5 M, and limits of detection were 0.74 and 1.3 μg/mL for SDZ and for SMX, respectively. Good selectivity with log Kpot < −0.3 was observed for carbonate, chloride, fluoride, hydrogenocarbonate, nitrate, nitrite, phosphate, cyanide, sulfate, borate, persulphate, citrate, tartrate, salicylate, tetracycline, ciprofloxacin, sulphamerazine, sulphatiazole, dopamine, glucose, galactose, cysteine and creatinine. The best sensors were successfully applied to the analysis of real samples with relative errors ranging from −6.8 to + 3.7%.

A new biomimetic sensor for detecting carnitine, a potential biomarker in ovarian cancer

1st ASPIC International Congress

Fatal disseminated paracoccidioidomycosis in a two-year-old child

A two year-old female child was admitted at the Pediatric Intensive Care Unit in a septic shock associated with a lymphoproliferative syndrome, with history of fever, adynamia and weight loss during the last two months. On admission, the main clinical and laboratory manifestations were: pallor, jaundice, disseminated enlarged lymph nodes, hepatosplenomegaly, crusted warts on face, anemia, eosinophilia, thrombocytopenia, increased direct and indirect bilirubin, alkaline phosphatase, and gammaglutamyl transpeptidase. A parenteral administration of fluids, dobutamine and mechanical ventilation was started, without improvement of the clinical conditions. A direct examination of exsudate collected from cervical lymph node revealed numerous oval-to-around cells with multiple budding, like a "pilot wheel" cell, suggesting Paracoccidioides brasiliensis. Even though treatment with intravenous sulfamethoxazole-trimethoprine was soon started, the child died 36 hours after hospital admission. Disseminated paracoccidioidomycosis was confirmed in the autopsy. This is the youngest case of paracoccidioidomycosis in children reported in the literature.

A disposable glass-based immunosensor for monitoring the cancer biomarker CEA in urine

NanoPT 2014 International Conference, in Portugal, on February 12-14. Poster presentation based on topic Nanobio/Nanomedicine

Human vaccinia-like virus outbreaks in São Paulo and Goiás States, Brazil: virus detection, isolation and identification

Since October 2001, the Adolfo Lutz Institute has been receiving vesicular fluids and scab specimens of patients from Paraíba Valley region in the São Paulo and Minas Gerais States and from São Patricio Valley, in the Goiás State. Epidemiological data suggested that the outbreaks were caused by Cowpox virus or Vaccinia virus. Most of the patients are dairy milkers that had vesiculo-pustular lesions on the hands, arms, forearms, and some of them, on the face. Virus particles with orthopoxvirus morphology were detected by direct electron microscopy (DEM) in samples of 49 (66.21%) patients of a total of 74 analyzed. Viruses were isolated in Vero cell culture and on chorioallantoic membrane (CAM) of embryonated chicken eggs. Among 21 samples submitted to PCR using primers for hemagglutinin (HA) gene, 19 were positive. Restriction digestion with TaqI resulted in four characteristic Vaccinia virus fragments. HA nucleotide sequences showed 99.9% similarity with Cantagalo virus, described as a strain of Vaccinia virus. The only difference observed was the substitution of one nucleotide in the position 616 leading to change in one amino acid of the protein in the position 206. The phylogenetic analysis showed that the isolates clustered together with Cantagalo virus, other Vaccinia strains and Rabbitpox virus.

Dapsone hypersensitivity syndrome in an adolescent during treatment during of leprosy

A 12 y old girl was admitted 24 days after start a WHO multidrug therapy scheme for multibacillary leprosy (dapsone, clofazimine and rifampicin) with intense jaundice, generalized lymphadenopathy, hepatoesplenomegaly, oral erosions, conjunctivitis, morbiliform rash and edema of face, ankles and hands. The main laboratory data on admission included: hemoglobin, 8.4 g/dL; WBC, 15,710 cells/mm³; platelet count, 100,000 cells/mm³; INR = 1.49; increased serum levels of aspartate and alanine aminotransferases, gamma-glutamyl transpeptidase, alkaline phosphatase, direct and indirect bilirubin. Following, the clinical conditions had deteriorated, developing exfoliative dermatitis, shock, generalized edema, acute renal and hepatic failure, pancytopenia, intestinal bleeding, pneumonia, urinary tract infection and bacteremia, needing adrenergic drugs, replacement of fluids and blood product components, and antibiotics. Ten days after admission she started to improve, and was discharged to home at day 39th, after start new supervised treatment for leprosy with clofazimine and rifampicin, without adverse effects. This presentation fulfils the criteria for the diagnosis of dapsone hypersensitivity syndrome (fever, generalized lymphadenopathy, exfoliative rash, anemia and liver involvement with mixed hepatocellular and cholestatic features). Physicians, mainly in geographical areas with high prevalence rates of leprosy, should be aware to this severe, and probably not so rare, hypersensitivity reaction to dapsone.

Diffusion characteristics of ethylene glycol in skeletal muscle

Part of the optical clearing study in biological tissues concerns the determination of the diffusion characteristics of water and optical clearing agents in the subject tissue. Such information is sufficient to characterize the time dependence of the optical clearing mechanisms—tissue dehydration and refractive index (RI) matching. We have used a simple method based on collimated optical transmittance measurements made from muscle samples under treatment with aqueous solutions containing different concentrations of ethylene glycol (EG), to determine the diffusion time values of water and EG in skeletal muscle. By representing the estimated mean diffusion time values from each treatment as a function of agent concentration in solution, we could identify the real diffusion times for water and agent. These values allowed for the calculation of the correspondent diffusion coefficients for those fluids. With these results, we have demonstrated that the dehydration mechanism is the one that dominates optical clearing in the first minute of treatment, while the RI matching takes over the optical clearing operations after that and remains for a longer time of treatment up to about 10 min, as we could see for EG and thin tissue samples of 0.5 mm.

Frequency of hepatitis B immunity and occupational exposures to body fluids among brazilian medical students at a public university

In the present study the frequencies of immunity against hepatitis B (HB) and of potentially contaminating accidents among medical students of a Brazilian public university were evaluated. Of all the 400 students who should have been immunized, 303 (75.7%), 66.3% of whom were women, answered an anonymous, self-administered questionnaire. Serum anti-HBs were determined in 205 of them and titers > 10 UI/L were considered to be protective. A total of 86.8% of students had received three doses of HB vaccine. The frequency of immunity among women (96.4%) was higher (p = 0.04) than that among men (87.7%). Among those who did not have immunity, 12/13 (92.3%) had been vaccinated before entering medical school. Only 11% of the students with complete vaccination had previously verified serological response to the vaccine. A total of 23.6% reported having been somehow exposed to blood or secretions. Among final-year students, this frequency was 45.0%, being similar among men (47.8%) and women (43.2%). Of all these accidents, 57.7% were due to body fluids coming in contact with mucosa and 42.3% due to cut and puncture accidents. The results from this study show that: 1) the frequency of immunity against HB is high among the evaluated medical students, although verification of response to vaccination is not a concern for them; 2) anti-HBs titers should be verified after complete vaccination and on a regular basis, especially by men; and 3) the frequency of potentially contaminating accidents is high.

OCCUPATIONAL EXPOSURES TO BODY FLUIDS AND BEHAVIORS REGARDING THEIR PREVENTION AND POST-EXPOSURE AMONG MEDICAL AND NURSING STUDENTS AT A BRAZILIAN PUBLIC UNIVERSITY

A cross-sectional study was conducted to assess the frequencies and characteristics of occupational exposures among medical and nursing students at a Brazilian public university, in addition to their prevention and post-exposure behavior. During the second semester of 2010, a self-administered semi-structured questionnaire was completed by 253/320 (79.1%) medical students of the clinical course and 149/200 (74.5%) nursing students who were already performing practical activities. Among medical students, 53 (20.9%) suffered 73 injuries, which mainly occurred while performing extra-curricular activities (32.9%), with cutting and piercing objects (56.2%), in the emergency room (39.7%), and as a result of lack of technical preparation or distraction (54.8%). Among nursing students, 27 (18.1%) suffered 37 injuries, which mainly occurred with hollow needles (67.6%) in the operating room or wards (72.2%), and as a result of lack of technical preparation or distraction (62.1%). Among medical and nursing students, respectively, 96.4% and 48% were dissatisfied with the instructions on previously received exposure prevention; 48% and 18% did not always use personal protective equipment; 67.6% and 16.8% recapped used needles; 49.3% and 35.1% did not bother to find out the source patient's serological results post-exposure; and 1.4% and 18.9% officially reported injuries. In conclusion, this study found high frequencies of exposures among the assessed students, inadequate practices in prevention and post-exposure, and, consequently, the need for training in “standard precautions” to prevent such exposures.

FREQUENCY OF Candida SPECIES IN A TERTIARY CARE HOSPITAL IN TRIANGULO MINEIRO, MINAS GERAIS STATE, BRAZIL

Infections by Candida species are a high-impact problem in public health due to their wide incidence in hospitalized patients. The goal of this study was to evaluate frequency, susceptibility to antifungals, and genetic polymorphism of Candida species isolated from clinical specimens of hospitalized patients. The Candida isolates included in this study were obtained from blood cultures, abdominal fluids, and central venous catheters (CVC) of hospitalized patients at the Clinical Hospital of the Federal University of Uberlândia during the period of July 2010 - June 2011. Susceptibility tests were conducted by the broth microdilution method. The RAPD-PCR tests used employed initiator oligonucleotides OPA09, OPB11, and OPE06. Of the 63 Candida isolates, 18 (28.5%) were C. albicans, 20 (31.7%) were C. parapsilosis complex species, 14 (22.2%) C. tropicalis, four (6.4%) C. glabrata, four (6.4%) C. krusei, two (3.3%) C. kefyr, and one (1.6%) C. lusitaniae. In vitro resistance to amphotericin B was observed in 12.7% of isolates. In vitroresistance to azoles was not detected, except for C. krusei. The two primers, OPA09 and OPB11, were able to distinguish different species. Isolates of C. albicans and C. parapsilosis complex species presented six and five clusters, respectively, with the OPA09 marker by RAPD-PCR, showing the genetic variability of the isolates of those species. It was concluded that members of the C. parapsilosis complex were the most frequent species found, and most isolates were susceptible to the antifungals amphotericin B, flucozanole, and itraconazole. High genetic polymorphisms were observed for isolates of C. albicans and C. parapsilosis complex species, mainly with the OPA09 marker.

The hamster (mesocricetus auratus) as experimental model in chagas' disease: parasitological and histopathological studies in acute and chronic phases of Trypanosoma cruzi infection

This research characterizes the acute and chronic phases of Chagas ' disease in hamster through parasitological and histopathological studies. The acute phase was achieved with 44 young hamsters injected intraperitoneally with 100.000 blood trypomastigotes of Benedito and Y strains of T. cruzi. The chronic phase was induced in 46 hamsters injected intraperitoneally with 35.000 trypomastigotes ofVicentina, Benedito and Y strains. Animals were sacrificed at regular intervals of 24 hours of acute phase and from the 3rd to the 10th month of infection ofchronic phase. In the acute phase, parasites were easily recoveredfrom all animals and there was an inflammatory reaction characterized by mononuclear and polymorphous leukocyte infiltration of variable degree in the majority of tissues and organs, specially in the connective loose and fatty tissues, smooth muscle myocardium and skeletal muscle. In the chronic phase the lesions occurred in the same tissues and organs, but the inflammatory response was less severe and characterized by mononuclear infiltration mainly with focal or zonalfibrosis in the myocardiun. In 50% of infected animals parasites were found inmyocardiun and recoveredfrom pericardic, peritoneal and ascitic fluids in some animals. Signs of heart failure, sudden death and enlargement of bowel were observed regularly. We concluded that the hamster is an useful model for Chagas' disease studies.

Seroprevalence of hepatitis B virus infection and seroconvertion to anti-HBsAg in laboratory staff in Goiânia, Goiás

Were analyzed 648 serum samples from laboratory staff in Goiânia, Goiás aiming detection of three serological markers of HBV: HBsAg, anti-HBsAg and anti-HBcAg. The HBsAg and anti-HBcAg positive samples were also analyzed for HBeAg, anti-HBeAg and anti-HBcAgIgM markers. HBV infection rate of 24.1% was observed and, from them, 0.7% were positive for HBsAg. Viral DNA was detected by PCR in two HBsAg positive samples. A vaccination index of 74.5% and a global index of 89.9% of serological response to vaccination were observed. The direct work with biological fluids as well as cleaning workers represented significant risks for acquisition of HBV infection. The data from the present study showed an increase of the vaccination index among laboratory staff but the rates of HBV infection did not change through the years in the region.

Correction of the anisotropy in resistivity: application to pore pressure prediction

Dissertação para obtenção do Grau de Mestre em Engenharia Geológica (Georrecursos)