Toxicity assessment of oil field produced water treated by evaporative processes to produce water to irrigation.

During the productive life of an oil well, a high quantity of produced water is extracted together with the oil, and it may achieve up to 99% in the end of the well's economical life. Desalination is one of mankind's earliest forms of saline water treatment, and nowadays, it is still a common process used throughout the world. A single-effect mechanical vapor compression (MVC) process was tested. This paper aims to assess the potential toxicity of produced water to be re-used in irrigation. Samples of both produced and distilled water were evaluated by 84 chemical parameters. The distilled produced water presented a reduction up to 97% for the majority of the analyzed parameters, including PAHs. Toxicity bioassays were performed with distilled produced water to evaluate the growth inhibition of Pseudokirchneriella subcapitata algae, the acute toxicity to Danio rerio fish, the germination inhibition of Lactuca sativa vegetable and the severity of toxicity, as well as behavior test with Lumbricid Earthworm Eisenia fetida. The ecotoxicological assays results showed no toxicity, indicating that the referred evaporative process can produce water to be reused in irrigation.

Failure of protection induced by a Brazilian vaccine against Brazilian wild rabies viruses.

This report shows that the SMB vaccine currently used in Brazil for human immunisation provides different degrees of protection in mice, depending on the rabies virus strain used as challenge. Using the NIH and Habel potency tests to evaluate the protective activity of rabies vaccine, we observed that vaccinated mice showed a higher resistance to a challenge with a fixed rabies virus (CVS-Challenge Virus Strain). The vaccine potency using the Habel or NIH tests was respectively > 6.4 (log 10) and 1.0 (Relative Potency-RP) when the fixed rabies virus was used for challenge, and from 2.9 to 4.3 (log 10) or 0.13 to 0.8 (RP) when different wild rabies viruses were used for challenge. The presence of virus neutralising antibodies (VNA) could not explain the differences of susceptibility after vaccination, since sera of vaccinated animals had similar VNA levels against both fixed and wild strains before virus challenge (respectively, 5.6 +/- 0.24 and 5.0 +/- 0.25 IU/ml of VNA against the fixed rabies virus and the 566-M strain of wild rabies virus in sera of mice vaccinated with 0.2 units of vaccine). Only cell-mediated immunity parameters correlated with the protection induced by vaccination. The IFN gamma titers found in sera and brain tissues of animals challenged with CVS strain were higher (from 36.7 +/- 5.7 to 293.3 +/- 46.2 IU/ml) than those found in mice challenged with 566-M virus strain (from 16.7 +/- 5.8 to 36.7 +/- 5.8). The proliferation index of spleen cells obtained with CVS stimulation reached a maximal value of 15.1 +/- 0.7 while spleen cells from vaccinated mice stimulated with 566-M virus failed to proliferate. The implications of these data in human protection by vaccination are discussed.

Short duration of neutralizing antibody titers after pre-exposure rabies vaccination with suckling mouse brain vaccine

The human anti-rabies pre-exposure treatment currently used in Brazil, employing a 1-ml dose of suckling mouse brain vaccine (SMBV) administered on days 0, 2, 4 and 28, was compared to an alternative treatment with two 1 ml-doses on day 0, and one 1 ml-dose injected on days 7 and 21. The latter induced higher virus-neutralizing antibody (VNA) titers on day 21. Both Brazilian rabies vaccines produced with PV or CVS rabies virus strains were tested. Two additional volunteer vaccinee groups, receiving the pre-exposure and the abbreviated post-exposure schedules recommended by the WHO using cell-culture vaccine (CCV) produced with PM rabies virus strain, were included as reference. The VNA were measured against both PV and CVS strains on days 21, 42 and 180 by the cell-culture neutralization microtest. The PV-SMBV elicited higher seroconversion rates and VNA by day 21 than the CVS-SMBV. Both, however, failed to induce a long-term immunity, since VNA titers were <0.5 IU/ml on day 180, regardless of the schedule used. Cell-culture vaccine always elicited very high VNA on all days of collection. When serum samples from people receiving mouse brain tissue were titrated against the PV and CVS strains, the VNA obtained were similar, regardless of the vaccinal strain and the virus used in the neutralization test. These results contrast with those obtained with sera from people receiving PM-CCV, whose VNA were significantly higher when tested against the CVS strain.

Short duration of neutralizing antibody titers after pre-exposure rabies vaccination with suckling mouse brain vaccine.

The human anti-rabies pre-exposure treatment currently used in Brazil, employing a 1-ml dose of suckling mouse brain vaccine (SMBV) administered on days 0, 2, 4 and 28, was compared to an alternative treatment with two 1 ml-doses on day 0, and one 1 ml-dose injected on days 7 and 21. The latter induced higher virus-neutralizing antibody (VNA) titers on day 21. Both Brazilian rabies vaccines produced with PV or CVS rabies virus strains were tested. Two additional volunteer vaccine groups, receiving the pre-exposure and the abbreviated post-exposure schedules recommended by the WHO using cell-culture vaccine (CCV) produced with PM rabies virus strain, were included as reference. The VNA were measured against both PV and CVS strains on days 21, 42 and 180 by the cell-culture neutralization microtest. The PV-SMBV elicited higher seroconversion rates and VNA by day 21 than the CVS-SMBV. Both, however, failed to induce a long-term immunity, since VNA titers were < 0.5 IU/ml on day 180, regardless of the schedule used. Cell-culture vaccine always elicited very high VNA on all days of collection. When serum samples from people receiving mouse brain tissue were titrated against the PV and CVS strains, the VNA obtained were similar, regardless of the vaccinal strain and the virus used in the neutralization test. These results contrast with those obtained with sera from people receiving PM-CCV, whose VNA were significantly higher when tested against the CVS strain.

[Humoral immune response of dogs to the inactivated suckling mouse brain vaccine used in anti-rabies campaigns in Brazil]. / Resposta imune humoral de cães à vacina inativada, de cérebro de camundongos lactentes, utilizada nas campanhas anti-rábicas no Brasil.

INTRODUCTION: An anti-rabies campaign is undertaken annually in Brazil with of the Fuenzalida & Palacios vaccine. The humoral immune response of dogs vaccinated during the campaigns was researched with the objective of evaluating whether the dogs presented a protective titer (0.5 UI/ml) 12 months after vaccination and how many of these achieved this titer 30 days after a buttressing vaccination. MATERIAL AND METHOD: Three hundred and forty-one specimens of serum of dogs domicilied, 259 in the S. Paulo and 82 in the Paulinia counties, were analyzed utilizing the Rapid Fluorescence Focus Inhibition Test. The immune response was evaluated taking into consideration the nutritional state of the animal and the number of previous vaccinations. RESULTS: The larger number of the dogs had not achieved the 0.5 UI/ml titer after 12 months, independently of the nutritional state and the response to the buttressing vaccination was more apparent in dogs with two or more previous vaccinations. DISCUSSION: The cut off of 0.5 UI/ml as protective titer in dogs and the influence of the nutritional state and health conditions of the animals as responsible for humoral immune response are discussed.

Studies on human anti-rabies immunization in Brazil. I--Evaluation of the 3 + 1 pre-exposure vaccination schedule under field conditions.

The currently used pre-exposure anti-rabies immunization schedule in Brazil is the one called 3+1, employing suckling mouse brain vaccine (3 doses on alternate days and the last one on day 30). Although satisfactory results were obtained in well controlled experimental groups using this immunization schedule, in our routine practice, VNA levels lower than 0.5 IU/ml are frequently found. We studied the pre-exposure 3+1 schedule under field conditions in different cities on the State of São Paulo, Brazil, under variable and sometimes adverse circumstances, such as the use of different batches of vaccine with different titers, delivered, stored and administered under local conditions. Fifty out of 256 serum samples (19.5%) showed VNA titers lower than 0.5 IU/ml, but they were not distributed homogeneously among the localities studied. While in some cities the results were completely satisfactory, in others almost 40% did not attain the minimum VNA titer required. The results presented here, considered separately, question our currently used procedures for human pre-exposure anti-rabies immunization. The reasons determining this situation are discussed.

Studies on human anti-rabies immunization in Brazil. II--Preliminary evaluation of the 2-1-1 schedule for human pre-exposure anti-rabies immunization, employing suckling mouse brain vaccine.

This study reports preliminary results of virus neutralizing antibody (VNA) titers obtained on different days in the course of human anti-rabies immunization with the 2-1-1 schedule (one dose is given in the right arm and one dose in the left arm at day 0, and one dose is applied on days 7 and 21), recommended by WHO for post-exposure treatment with cell culture vaccines. A variant schedule (double dose on day zero and another on day 14) was also tested, both employing suckling mouse brain vaccine. A complete seroconversion rate was obtained after only 3 vaccine doses, and almost all patients (11 of 12) presented titers higher than 1.0 IU/ml. Both neutralizing response and seroconversion rates were lower in the group receiving only 3 doses, regardless of the sample collecting day. Although our results are lower than those found with cell culture vaccines, the geometry mean of VNA is fully satisfactory, overcoming the lower limit recommended by WHO of 0.5 IU/ml. The 2-1-1 schedule could be an alternative one for pre exposure immunization, shorter than the classical 3+1 regimen (one dose on days 0, 2, 4 and 30) with only three visits to the doctor, instead of four.

Immunomodulatory effect of glucan on the response to experimental antirabies vaccination.

The objective of the present study was to determine the stimulatory response to antirabies vaccination promoted by glucan in mice. Glucan increased both resistance to infection and antibody titres and this effect was more evident when glucan was used at dose of 0.5 mg, administered intraperitoneally before, during and after immunization and when the challenge virus was applied to the foot-pad.

[An error in the administration of rabies serum vaccination. The use of an improvised schedule and its evaluation: report of a case]. / Engano na administração de soro-vacinação para raiva. Emprego de esquema improvisado e sua avaliação: apresentação de um caso.

We report on a female patient attacked by a dog that died 4 days later, who sought treatment 11 days after the accident. A serum vaccination schedule was indicated, to be started immediately with the administration of anti-rabies serum (9 ml, corresponding to 40 IU/Kg body weight) and a series of 10 doses of vaccine applied on consecutive days plus 3 booster doses applied at 10-day intervals, according to the regulations of the Health Secretariat of the State of São Paulo. However, due to an error, 9 vaccine doses were initially applied at 3 different anatomical sites. The error was immediately discovered and it was decided to interrupt treatment for a few days and to restart and complete it later; this was done only 8 days later. Serologic follow-up by the serum-neutralization test in cell culture revealed a fully satisfactory response greatly exceeding WHO recommendations in terms of levels, precocity and duration. The patient continued to be healthy by the 240th day after the accident, when she was observed for the last time before this publication.

Reduced schedule of human anti-rabies immunization with Fuenzalida & Palacios vaccine. Additional data

It was reevaluated a reduced schedule for anti-rabies post-exposure immunization with newborn mice nervous tissue vaccine (Fuenzalida & Palacios) in a group of 30 non exposed volunteers. The vaccine was administered by intramuscular injections on days zero, 2, 4, 16 and 27, in the deltoid area. Antibody levels were determinated by a simplified serum neutralization microtest on days zero, 16 and 37. On days 16 and 37 the antibody levels of the whole group was > or = 0.5 IU/ml and > or = 1.0 IU/ml, respectively. The cell mediated immunity was precociously detected (on day 4) by the delayed type hypersensitivity skin test. Our results show that this reduced schedule elicited an early and effective humoral and cellular immune response. However it is necessary other studies with larger groups of vaccinees in order to obtain definitive conclusion.

Reduced schedule of human anti-rabies immunization with Fuenzalida & Palacios vaccine. Additional data.

It was reevaluated a reduced schedule for anti-rabies post-exposure immunization with newborn mice nervous tissue vaccine (Fuenzalida & Palacios) in a group of 30 non exposed volunteers. The vaccine was administered by intramuscular injections on days zero, 2, 4, 16 and 27, in the deltoid area. Antibody levels were determinated by a simplified serum neutralization microtest on days zero, 16 and 37. On days 16 and 37 the antibody levels of the whole group was > or = 0.5 IU/ml and > or = 1.0 IU/ml, respectively. The cell mediated immunity was precociously detected (on day 4) by the delayed type hypersensitivity skin test. Our results show that this reduced schedule elicited an early and effective humoral and cellular immune response. However it is necessary other studies with larger groups of vaccinees in order to obtain definitive conclusion.

Simplified fluorescent inhibition microtest for the titration of rabies neutralizing antibodies

A simplified fluorescence inhibition microtest (SFIMT) was standardized for the evaluation of antirabies serum neutralizing antibodies based on the rapid fluorescent focus inhibition test (RFFIT) and the fluorescence inhibition microtest (FIMT). The simplified test showed reproducibility similar to that of the FIMT with advantages as easier executation and quicker reading. A simple pre-treatment of Brazilian microplates produced for immune enzymatic assays (PROSIL) gave equivalent results and substantial coast reduction, in relation to imported plates (DIFCO). The simplified test can be easily implemented in less sophisticated laboratories, as alternative to the mouse serum neutralization test, still the most largely employed in Brazil, or even to others as RFFIT and FIMT.

Simplified fluorescent inhibition microtest for the titration of rabies neutralizing antibodies.

A simplified fluorescence inhibition microtest (SFIMT) was standardized for the evaluation of antirabies serum neutralizing antibodies based on the rapid fluorescent focus inhibition test (RFFIT) and the fluorescence inhibition microtest (FIMT). The simplified test showed reproducibility similar to that of the FIMT with advantages as easier executation and quicker reading. A simple pre-treatment of Brazilian microplates produced for immune enzymatic assays (PROSIL) gave equivalent results and substantial coast reduction, in relation to imported plates (DIFCO). The simplified test can be easily implemented in less sophisticated laboratories, as alternative to the mouse serum neutralization test, still the most largely employed in Brazil, or even to others as RFFIT and FIMT.

Simplification of immune adherence hemagglutination test for detection of rabies antibodies in human serum.

In the present work the immune adherence hemagglutination test (IAHA) was standardized in a simplified procedure. This test showed good reproducibility, better than the classical mice serum neutralization test (SN). The tests showed high correlation degree: high titers in one test corresponded to high titers in the other one, and the same occurred with low titers. The IAHA test is extremely simple, fast to perform, and of low cost when compared to tests such as SN or indirect immunofluorescence (IIF). It also proved to be useful in less sophisticated laboratories or even as a screening test for the titration of rabies antibodies.

Reduced schedule of human antirabies immunization with Fuenzalida & Palacios vaccine.

The present study evaluates the humoral and cellular immune responses in 35 volunteers submitted to short antirabies vaccination schedules with the Fuenzalida & Palacios vaccine based on the administration of doses on non consecutive days. The volunteers were divided into two groups. The first group received a total number of five doses given on days 0, 4, 7, 20 and 35. The other group received four doses, the first one being a double dose given on day 0 and than three other single doses on days 7, 20 and 35. The evaluation of humoral immune response was carried out by serum neutralization (SN) and indirect immunofluorescence (IIF) tests, while the cellular immune response was evaluated by lymphoblastic transformation assay (LTA) and skin test (ST). According to our results these reduced schedules elicited early and effective humoral and cellular immune responses to rabies antigen suggesting that new reduced schedules should be extensively studied in order to give the proper bases to the proposition of changes in the current long-term schedule.

Detection of classic and invasive E.coli and Shigella serotypes in stools by indirect immunofluorescence.

A imunofluorescencia indireta (IFI) de sorotipos enteropatogenicos classicos e invasores de E. coli e de Shigella foi comparada com os metodos tradicionais de coprocultura e soroaglutinacao. Os resultados da IFI concordaram com os da coprocultura em 128 dos 140 casos testados para E.coli enteropatogenica (91%) e em 108 dos 112 testados para Shigella (96%). Todos os casos com reacoes positivas por coprocultura foram confirmados por IFI. No grupo controle, onde nao haviam sido isolados tais patogenos por coprocultura, foram evidenciados por IFI, 12 casos com reacoes positivas para E. coli enteropatogenica e 4 para Shigella, incluindo-se 2 com infeccao mista: E. coli 026/Sh. dysenteriae e E. coli 0124/Sh. dysenteriae. Foi discutida a alta sensibilidade e especificidade da IFI quando comparada aos metodos tradicionais, sendo sugerido o valor desta tecnica em estudos epidemiologicos envolvendo os microrganismos em questao e sua importancia no estabelecimento de diagnostico precoce na diarreia infantil aguda