Modeling of coastal water contamination in Fortaleza (Northeastern Brazil).

An important tool in environmental management projects and studies due to the complexity of environmental systems, environmental modeling makes it possible to integrate many variables and processes, thereby providing a dynamic view of systems. In this study the bacteriological quality of the coastal waters of Fortaleza (a state capital in Northeastern Brazil) was modeled considering multiple contamination sources. Using the software SisBaHiA, the dispersion of thermotolerant coliforms and Escherichia coli from three sources of contamination (local rivers, storm drains and submarine outfall) was analyzed. The models took into account variations in bacterial decay due to solar radiation and other environmental factors. Fecal pollution discharged from rivers and storm drains is transported westward by coastal currents, contaminating strips of beach water to the left of each storm drain or river. Exception to this condition only occurs on beaches protected by the breakwater of the harbor, where counterclockwise vortexes reverse this behavior. The results of the models were consistent with field measurements taken during the dry and the rainy season. Our results show that the submarine outfall plume was over 2 km from the nearest beach. The storm drains and the Maceió stream are the main factors responsible for the poor water quality on the waterfront of Fortaleza. The depollution of these sources would generate considerable social, health and economic gains for the region.

Perfil de resistência antimicrobiana de Escherichia coli isoladas do açude Santo Anastácio, Ceará, Brasil / Resistance profile of Escherichia coli isolated from the environment

Este trabalho objetivou caracterizar a resistência antimicrobiana de 43 cepas de Escherichia coli isoladas do açude Santo Anastácio (Fortaleza, CE), durante os meses de janeiro a abril de 2007. As cepas foram submetidas a testes de suscetibilidade a oito antimicrobianos, tendo 67,4% delas apresentado sensibilidade a todos. Observou-se resistência à tetraciclina (25,6%), ao sulfazotrin (18,6%), ao ácido nalidixíco (9,3%) e a ciprofloxacina (4,7%). Nenhuma resistência foi observada aos betalactâmicos. Nove (21%) cepas apresentaram multirresistência, com um percentual de 78% para resistência cromossômica e 56% para resistência plasmidial. A presença de bactérias resistentes pode estar relacionada ao lançamento de antimicrobianos nas águas através de esgotos, sendo que o uso inadequado dessas águas pode comprometer a saúde da população.

The aim of this study was to determine the antimicrobial resistance of 43 Escherichia coli strains isolated from the Santo Antonio weir (Fortaleza, CE, Brazil) from January to April 2007. Susceptibility tests performed with 8 antimicrobials indicated that 67.5% of the strains were susceptible to all of them. Resistance to tetracycline (25.6%), sulfazotrim (18.6%), nalidixic acid (9.3%), and ciprofloxacin (4.7%) was observed. The strains did not show resistance to betalactamics. Nine strains (21%) were multiresistant, the resistance being chromosome (78%) and plasmid (56%) mediated. The presence of resistant bacteria may be related to antimicrobials in the sewage discharged into the weir, and the inappropriate use of this body of water may pose human health risks.

Multiple drug resistant Staphylococcus aureus strains isolated from a fish market and from fish handlers

The aim of this study was to investigate the presence of antibiotic resistant Staphylococcus aureus strains in fish stalls and in hands and nasal and oral cavities of fish handlers of the Mucuripe Fish Market, Fortaleza, Ceará, Brazil. All S. aureus isolates were resistant to Ampicillin and 44 percent were multi-drug resistant.

O objetivo da pesquisa foi investigar a presença de Staphylococcus aureus resistente a antibióticos nos boxes de venda de peixe e nas mãos e cavidades nasal e oral de manipuladores de pescado da Feira de Pescado do Mucuripe, Fortaleza, Ceará. Todas as cepas isoladas foram resistentes à ampicilina e 44 por cento apresentaram multiresistência.

The impact of shrimp farming effluent on bacterial communities in mangrove waters, Ceará, Brazil.

The effects of shrimp farm effluents on bacterial communities in mangroves have been infrequently reported. Classic and molecular biology methods were used to survey bacterial communities from four mangroves systems. Water temperature, salinity, pH, total heterotrophic bacteria and maximum probable numbers of Vibrio spp. were investigated. Genetic profiles of bacterial communities were also characterized by polymerase chain reaction (PCR) amplification of eubacterial and Vibrio 16S rDNA using denaturing gradient gel electrophoresis (DGGE). Highest heterotrophic counts were registered in the mangrove not directly polluted by shrimp farming. The Enterobacteriaceae and Chryseomonas luteola dominated the heterotrophic isolates. Vibrio spp. pathogenic to humans and shrimps were identified. Eubacterial genetic profiles suggest a shared community structure independent of mangrove system. Vibrio genetic profiles were mangrove specific. Neither microbial counts nor genetic profiling revealed a significant decrease in species richness associated with shrimp farm effluent. The complex nature of mangrove ecosystems and their microbial communities is discussed.

Biological relevance of E-cadherin-catenin complex proteins in primary epithelial ovarian tumours.

This study analysed the biological relevance of E-cadherin, alpha-catenin, beta-catenin and gamma-catenin immunoexpression pattern (reduced vs. preserved phenotype) in epithelial ovarian tumours. Immunohistochemistry was used to evaluate the expression of these proteins in 154 epithelial ovarian tumours, consisting of 17 benign, 33 borderline and 104 malignant tumours. In borderline tumours, the immunoexpression pattern of E-cadherin (p = 0.014) and alpha-catenin (p = 0.030) associated with histological type. In malignant tumours, the immunoexpression pattern of E-cadherin was related with histological type (p = 0.001). The immunoexpression pattern of beta-catenin associated with histological type and tumour differentiation (p = 0.005, p = 0.025, respectively). The preserved phenotype of E-cadherin was most frequently observed in mucinous tumours, whereas reduced E-cadherin was most frequently observed in serous tumours. The preserved phenotype of beta-catenin associated with endometrioid carcinomas, while reduced beta-catenin associated with poorly differentiated serous and clear cell carcinomas. Although the reduced phenotype was the most frequent immunoexpression observed for all proteins of the E-cadherin-catenin complex in epithelial ovarian tumours, only beta-catenin showed a significant difference between benign, borderline and malignant tumours (p = 0.045), since borderline and malignant tumours most frequently showed the reduced phenotype. The immunohistochemical profile of beta-catenin was shown to be of biological relevance: reduced beta-catenin was correlated with loss of tumour differentiation and serous carcinomas that are known to depict aggressive biological behaviour in epithelial ovarian tumours.

Resistência a antibióticos e a metais pesados de Escherichia coli isoladas de agua do mar e galerias pluviais / Resistance to antibiotics and heavy metals from Escherichia coli isolated from sea water and pluvial galeries

OBJECTIVE: Test the resistance to antibiotics and heavy metals of E. coli strains isolated from storm sewer water and adjacent seawater samples from three beaches (Meio, Area Preta and Ponta Negra) in the city of Natal/RN/Brazil, and determine the association among those characteristics. METHODS: A total of 98 strains of E. coli, 50 from storm sewers and 48 from the seawater were analyzed resistance to several antimicrobials by disk diffusion and agar dilution and to heavy metals by dilution in plates with aqueous solutions of CuSO4 incorporated to Mueller Hinton agar in concentrations of 100, 150, 200 and 250 ig/mL and HgCl2 in concentrations of 5, 10, 20, 30, and 50 ig/mL. Standard strains were used as control. RESULTS: Among the twelve antimicrobials tested, 28 (28.5%) of E. coli strains showed resistance to different antimicrobials drugs to seven. The greatest resistance rate was to tetracycline (46.4%), ampicillin (39.3%) and cephalothin (32.1%), with the remainder (nitrophurantoine, nalidixic acid, sulfatomexazol-trimethoprin and chloramphenicol) at lower percentages. Among the heavy metals, all the strains (100%) were resistant to zinc and to copper in the largest concentration (250 ig/mL), and 18.4% were resistant to HgCl the 50 ig/mL. Ten (55.5%) of the E. coli strains resistant to Hg were associated to resistance to antibiotics. CONCLUSION: These results suggest the existence of extra chromosomal genes in E. coli strains isolated from storm sewer water and adjacent seawater, which encoders of the resistance to antibiotics and heavy metals.

A cólera no Estado do Rio Grande do Norte--Brasil--perfil sorológico e de sensibilidade do Vibrio cholerae a diferentes antimicrobianos / Cholera in Rio Grande do Norte State--Brazil: sorology and sensitivity of Vibrio cholerae to different antimicrobials

PURPOSE: The emergence of multiple resistance to antimicrobials in Vibrio cholerae isolated in the state of Ceará, Brazil, alerted researchers in this area to the sensitivity to antimicrobials of strains isolated in Rio Grande do Norte (RN), Brazil. METHODS: One hundred and four strains of V. cholerae of human origin, isolated by Laboratório Central de Saúde Pública Dr. Almino Fernandes, were serologically typified and evaluated for in vitro sensitivity to eight antibiotics belonging to different groups (polymyxine, tetracycline, chloramphenicol, nitrofurantoin, sulphazotrin, pefloxacine, erythromycine, ampicillin). The strains were collected from patients suspected of contracting choleric diarrhea in the year 1999, in Natal/RN/Brazil. RESULTS: From the sample total, 100 were identified as V. cholerae, serogroup O:1, biotype El Tor, with 99 (95.3%) belonging to serovar Ogawa and only 1 (0.9%) to serovar Inaba. The 4 remaining were characterized as non O:1 V. cholerae, with 3 (2.9%) biochemically identified as Heiberg type I and 1 (0.9%) as type II. All the V. cholerae serogroup O:1 strains were sensitive to tetracycline, chloramphenicol, sulphazotrin, pefloxacine, erythromycine and resistant to polymyxine. In relation to nitrofurantoin, only 1 was sensitive. Only 1 was resistant to ampicillin. The non O:1 V. cholerae strains were resistant to polymyxine. CONCLUSIONS: The results showed sensitivity in 100% of the V. cholerae serogroup O:1 strains to tetracycline, an elective drug in the treatment of cholera, and an absence of multiple resistant strains in our environment. An interesting finding was the frequency of serovar Ogawa in 1999, considering the greater incidence of serovar Inaba in other years of cholera outbreaks in RN.

Vibrio vulnificus as a health hazard for shrimp consumers.

Over the last 30 years, a number of Vibrio species found in the aquatic environment have been indicated as cause of disease in human beings. Vibrio vulnificus is an emergent pathogen, an invasive and lethal marine bacterium related to wound infection and held accountable for gastroenteritis and primary septicemia. It occurs quite frequently in marine organisms, mainly in mollusks. This study aimed at isolating and identifying strains of V. vulnificus based upon the analysis of twenty samples of seabob shrimp, Xiphopenaeus kroyeri (Heller), purchased at the Mucuripe fish market (Fortaleza, Brazil). TCBS agar was used to isolate suspect strains. Seven of twenty-nine strains isolated from six different samples were confirmed as such by means of biochemical evidence and thus submitted to biological assays to determine their virulence. The susceptibility of the V. vulnificus strains to a number of antibiotics was tested. None of the V. vulnificus strains showed signs of virulence during a 24-hour observation period, possibly due to the shedding of the capsules by the cells. As to the results of the antimicrobial susceptibility tests, the seven above-mentioned V. vulnificus strains were found to be sensitive to nitrofurantoin (NT), ciprofloxacin (CIP), gentamicin (GN) and chloramphenicol (CO) and resistant to clindamycin (CI), penicillin (PN) and ampicillin (AP).

Microbicidal effect of medicinal plant extracts (Psidium guajava Linn. and Carica papaya Linn.) upon bacteria isolated from fish muscle and known to induce diarrhea in children.

Out of the twenty-four samples of shrimp and fish muscle used for this study, twelve were collected near a large marine sewer for waste disposal, 3 km off the coast of Fortaleza (Brazil) and used for the isolation of E. coli. Other twelve were collected at the Mucuripe fresh fish market (Fortaleza, Brazil) and used for the isolation of Staphylococcus aureus. Ethanol, water and acetone-diluted extracts of guava and papaya leaf sprouts were tested on the bacteria in order to verify their microbicidal potential. The E. coli strains used in the trials were rated LT positive. The papaya leaf extracts (Carica papaya Linn) showed no microbicidal activity while the guava sprout extracts (Psidium guajava Linn) displayed halos exceeding 13 mm for both species, an effect considered to be inhibitory by the method employed. Guava sprout extracts by 50% diluted ethanol most effectively inhibited E. coli (EPEC), while those in 50% acetone were less effective. It may be concluded that guava sprout extracts constitute a feasible treatment option for diarrhea caused by E. coli or by S. aureus-produced toxins, due to their quick curative action, easy availability in tropical countries and low cost to the consumer.

Biosorption: a solution to pollution?

To solve the water pollution problem by toxic heavy metal contamination resulting from humans technological activities has for long presented a challenge. Biosorption can be a part of the solution. Some types of biosorbents such as seaweeds, molds, yeasts, bacteria or crab shells are examples of biomass tested for metal biosorption with very encouraging results. The uptake of heavy metals by biomass can in some cases reach up to 50% of the biomass dry weight. New biosorbents can be manipulated for better efficiency and multiple re-use to increase their economic attractiveness.

Survival of Vibrio cholerae 01 strains in shrimp subjected to freezing and boiling.

This research was undertaken to assess the resistance of Vibrio cholerae 01 strains inoculated into white shrimp, Penaeus schimitti, to heating and freezing treatments. Shrimp samples with and without carapace were obtained from Sao Luis, Brazil. Microbial analysis revealed the presence of marine vibrios including Vibrio alginolyticus, Vibrio parahaemolyticus, and other vibrios and aerobic gram-negative and gram-positive bacteria that grew on selective medium, thiosulfate-citrate-bile salt-sucrose agar. Samples with and without carapaces were heated before inoculating with cells of V. cholerae and then one-half of the samples was stored frozen at -200 degrees C and the other one-half was heated to boiling temperatures. Viable cells of the test organism were recovered from samples without carapaces, stored under frozen conditions, after 36 days. In contrast, no living cells were recovered after 26 days from samples with carapaces. Boiling temperatures were very damaging to V. cholerae 01 in shrimp samples with and without carapaces. Total destruction of the cells occurred within 1 to 2 min of exposure to heating.

Colimetry of marine waters off Fortaleza (Ceará State, Brazil) and detection of enteropathogenic Escherichia coli strains.

Bacteriological analyses of seawater from three main beaches in Fortaleza, Brazil were performed during 1997. Thirty-six samples per beach were collected for a total of 108 samples. For Meireles Beach, 44% of the samples had MPN total coliforms values of at least 1100 or over 2400/100 ml, followed by Formosa and Diários beaches showing lower counts. For fecal coliforms the highest numbers were demonstrated for Formosa, followed by Meireles and Diários beaches in this descending order: 13.0%, 11.1% and 8.3%, respectively. Escherichia coli strains were identified in 76.8% of the 108 samples. Among 295 strains of E. coli, 21 belonged to serogroups O25, O26, O91, O112, O119, O158 and O164. Strains from serogroup O26 were tested using PCR, ELISA and Vero cells to detect Verotoxins VT1 and VT2 and all strains were negative. No LT and ST, as determined by ELISA and suckling mice assays, were detected among the 295 strains. All strains of E. coli were sensitive to ampicillin, cephalothin, gentamicin, tetracycline, sulfametox-trimethoprim, chloramphenicol and ciprofloxacin. Although the E. coli strains were not toxigenic, their presence in high numbers could be of public health significance.

Coliforms and Salmonella in seawater near to domestic sewage sources in Fortaleza (Ceará, Brazil).

The bacteriological conditions of the coastal region of Fortaleza (Ceará, Brasil), including the coastal zones of the Ceará and Cocó rivers, were examined. The study was conducted during June, September and December 1993, and March 1994. The region was divided into two areas: (i) Direct Influence Area (DIA), consisting of 20 sampling stations located near to discharge zones of the submarine pipeline system, where collections were carried out at the surface, and (ii) Indirect Influence Area (IIA), located near to the coastal zone, including Barra do Ceará, Kartódromo, Volta de Jurema, Mucuripe, Farol and Caça e Pesca beaches, totalling 26 sampling stations. The most probable number (MPN) of both total and fecal coliforms in DIA was positive only in station number 6, near to the sewage discharge exit. The following bacteria were identified: Citrobacter sp., Enterobacter aerogenes and Escherichia coli. Kartódromo beach was contaminated throughout the sampling period. Results of total fecal MPN was essentially lower than 3.0 x 10(2) coliforms/100 ml at Caça e Pesca beach. In December, at both DIA and IIA, Salmonella was identified in several samples. In DIA, the spatial distribution for Salmonella suggests that there should be a coastal sea current from east to west along the coastline. In IIA, Salmonella was identified at Kartódromo and Farol beaches throughout the sampling period.