When the resistance gets clingy: Pseudomonas aeruginosa harboring metallo-ß-lactamase gene shows high ability to produce biofilm.

The ability to produce biofilm and the presence of metallo-ß-lactamase (MBL) among Pseudomonas aeruginosa isolates were evaluated. A total of 91 isolates were recovered from sputa of patients with (CF, n = 44) and without (non-CF, n = 47) cystic fibrosis diagnosis. Seventy-nine (86.8%; 95% CI 78.3-92.3%) were biofilm producers. Interestingly, all isolates harboring MBL showed ability (most strong or moderate) to produce biofilm in vitro. We alert to an "overlapping of mechanisms" that together represent an even greater challenge for the treatment of pulmonary infections by P. aeruginosa.

Evaluation of biofilm production by Pseudomonas Aeruginosa isolates recovered from cystic fibrosis and non-cystic fibrosis patients

Cystic fibrosis (CF) patients typically suffer of persistent and recurrent lung infections caused by Pseudomonas aeruginosa that many times possess ability for the biofilm production. Here, biofilm production among P. aeruginosa isolates recovered from sputum of CF and non-CF patients was evaluated. Most isolates were biofilm-producing independently of the patient's condition.

Evaluation of biofilm production by Pseudomonas Aeruginosa isolates recovered from cystic fibrosis and non-cystic fibrosis patients.

Cystic fibrosis (CF) patients typically suffer of persistent and recurrent lung infections caused by Pseudomonas aeruginosa that many times possess ability for the biofilm production. Here, biofilm production among P. aeruginosa isolates recovered from sputum of CF and non-CF patients was evaluated. Most isolates were biofilm-producing independently of the patient's condition.

Evaluation of biofilm production by Pseudomonas Aeruginosa isolates recovered from cystic fibrosis and non-cystic fibrosis patients

Cystic fibrosis (CF) patients typically suffer of persistent and recurrent lung infections caused by Pseudomonas aeruginosa that many times possess ability for the biofilm production. Here, biofilm production among P. aeruginosa isolates recovered from sputum of CF and non-CF patients was evaluated. Most isolates were biofilm-producing independently of the patient's condition.

Frequency of Toxoplasma gondii in pork meat in Ocotlán, Jalisco, Mexico.

Toxoplasmosis is an infection caused by Toxoplasma gondii, an intracellular obligate parasite. Its transmission has usually been attributed to ingestion of undercooked or raw meat. The frequency of T. gondii in pork, the most common meat for human consumption in Jalisco, Mexico, is unknown; in Guadalajara city high prevalence of human toxoplasmosis has been documented. Forty-eight samples of pork meat from butcher shops in Ocotlán city were analyzed. Through bioassay, 50 g of tissue was homogenized in an acidic pepsin solution and inoculated subcutaneously to previously immunosuppressed mice. Blood samples from the mice tail vein were obtained before inoculation and 7, 14, 28, and 45 days postinoculation to analyze anti-Toxoplasma immunoglobulin (Ig) M and IgG antibody kinetics by indirect enzyme-linked immunosorbent assay. For histopathology, small fragments of the brain, lungs, heart, and skeletal muscle were extracted on day 45 and were stained with hematoxylin and eosin. Also, DNA was extracted from the pork meat for PCR amplification of the B1 gene. Even though all pork samples were negative by histopathology and PCR, IgG and IgM antibodies against T. gondii were detected in 1 of the 48 inoculated mice, reflecting a frequency of 2.1% positive pork meat, which is lower than expected but similar to that found in other regions.

Variations of agar screen tests for detection of methicillin resistance in staphylococci: focus on cefoxitin.

Members of the genus Staphylococcus are among the most important human pathogens, and strains demonstrating resistance to methicillin are an increasing problem worldwide, both within and outside of hospital environments. The objective of this study was to evaluate the use of variations of agar screening tests with cefoxitin and oxacillin to detect methicillin resistance in staphylococcal isolates. The agar screening test with cefoxitin (4 microg/ml) showed 99.4% accuracy for detecting both S. aureus and coagulase-negative staphylococci. The performance of the agar screening test with cefoxitin (4 microg/ml) either equaled or was superior to the other agar screening test variations evaluated and can be used to characterize the presence of the mecA gene among staphylococcal species.

Acute infection of Toxoplasma gondii and cytomegalovirus reactivation in a pediatric patient receiving liver transplant.

A 7-year-old Mexican boy with end-stage cirrhosis underwent liver transplantation and was maintained with cyclosporine and prednisolone. No specific data about Toxoplasma gondii or cytomegalovirus (CMV) infections in the cadaver donor were available. The recipient was seronegative for Toxoplasma, but CMV-IgG positive before transplantation. Ganciclovir was administered for prophylaxis during 3 months, but 5 months later he presented with icterus and increased transaminases. Acute transplant rejection was ruled out by biopsy. A seroconversion for T. gondii IgM and IgG and a small increase in CMV-IgM antibodies were observed, although the CMV-polymerase chain reaction (PCR) was negative. Ganciclovir was re-started, and the patient improved, but 6 months later he relapsed, and chorioretinitis lesions compatible both with T. gondii and CMV infections appeared. Pyrimethamine, sulfadiazine, folinic acid, and ganciclovir were administered. The boy showed favorable clinical improvement and remained stable for 12 months. Then, new retinal CMV lesions appeared in both eyes and the PCR for CMV became positive; therefore, the patient received a new regimen of ganciclovir, and clinically improved. From these data we concluded that the child presented a reactivation of CMV and a primary infection with T. gondii after transplantation.

[Outbreak of viral meningoencephalitis. Comparison of 2 biological systems used for isolation of the virus]. / Estudio de un brote de meningoencefalitis viral. Comparación de 2 sistemas biológicos empleados para el aislamiento.

An increase of the cases of viral meningoencephalitis was reported in our country from October to December, 1995. 23 faeces specimens were received from 2 provinces aimed at obtaining the viral isolation by their inoculation in cell culture and in newborn mice at the same time in order to compare the sensitivity of both systems in isolation. A higher number of isolations was obtained in cell culture. The cell culture from kidney of a normal adult green African monkey (Vero) proved to be more sensitive. 18 isolations were obtained and identified as Coxsackievirus B5. An anatomical and pathological study was conducted in inoculated mice and injuries compatible with the enteroviral infection were observed.

[The intratypic characterization of the poliovirus by the polymerase chain reaction technic]. / Caracterización intratípica de Poliovirus por la técnica de reacción en cadena de la polimerasa.

The polymerase chain reaction techniques was introduced for the intratypic characterization of Poliovirus. Primers were used only to promote the amplification of the Sabin vaccine strains proved by electrophoretic run of the amplified DNA products (Sabin 1-97 pb, Sabin 2-71 pb, Sabin 3-44 pb) and whose specificity was satisfactorily verified. 23 Cuban poliovirus strains isolated and identified at the Laboratory of Enterovirus of the "Pedro Kourí" Tropical Medicine Institute from 1993 to 1994 were studied by this technique. All of them were of the vaccine type. It was observed how the Sabin vaccine poliovirus may be the cause of viral meningoencephalitis as a milder neurological complication. This study provided one more evidence about the non circulation of the wild poliovirus in Cuba.

[Serologic study of patients with leptospirosis using TR antigen]. / Estudio serológico de pacientes con leptospirosis mediante el antígeno TR.

This paper deals with 254 monosera of patients with leptospirosis verified by macroagglutination test with thermoresistant antigen (TR antigen) and passive hemaglutination (HA), as reference technique. The TR antigen was elaborated according to the method described by Mailloux and coworkers, 1974, with modifications, and it showed a wide generic reactivity. It was specific when serologic test were performed with hyperimmune sera obtained from febrile disease producing bacteria and the causal agent of syphilis. The results obtained by both serologic tests were compared and it was observed that 106 sera (41.73%) were reactive to HA, which showed a highly significant statistical difference between the two techniques; so a lower sensibility of TR macroagglutination test was determined.