Comparative Studies of the (Anti) Mutagenicity of Baccharis dracunculifolia and Artepillin C by the Bacterial Reverse Mutation Test

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Bacterial sterilization by a dielectric barrier discharge (DBD) in air

Cold atmospheric plasma treatment of microorganisms and living tissues has become a popular topic in modern plasma physics and in medical science. The plasma is capable of bacterial inactivation and noninflammatory tissue modification, which makes it an attractive tool for treatment of skin diseases, open injuries and dental caries. Because of their enhanced plasma chemistry, Dielectric Barrier Discharges (DBDs) have been widely investigated for some emerging applications such as biological and chemical decontamination of media at ambient conditions. Despite the high breakdown voltage in air at atmospheric pressure, the average current of DBD discharges is low. Therefore, a DBD can be applied in direct contact with biological objects without causing any damage. In this work a 60 Hz DBD reactor, which generates cold atmospheric plasma inside Petri dishes with bacterial culture, is investigated. Samples of Staphylococcus aureus, a Gram-positive bacterium and Escherichia coil a Gram-negative bacterium were selected for this study. The bacterial suspensions were evenly spread on agar media planted in Petri dishes. The reactor electrodes were placed outside the Petri dish, thus eliminating the risk of samples microbial contamination. The covered Petri dish with agar medium in it serves as dielectric barrier during the treatment. The plasma processing was conducted at same discharge power (similar to 1.0 W) with different exposure time. Sterilization of E. coil and S. aureus was achieved for less than 20 min. Plasma induced structural damages of bacteria were investigated by Scanning Electron Microscopy. (C) 2010 Elsevier B.V. All rights reserved.

Bacterial cellulose-silica organic-inorganic hybrids

Bacterial cellulose (BC) hydrated membranes present nanometric reticulated structure that can be used as a template in the preparation of new organic-inorganic hybrids. BC-silica hybrids were prepared from BC membranes and tetraethoxysilane, (TEOS) at neutral pH conditions at room temperature. Macroscopically homogeneous membranes were obtained containing up to 66 wt.% of silica spheres, 20-30 nm diameter. Scanning electron micrographs clearly show the silica spheres attached to cellulose microfibrils. By removing the cellulose, the silica spheres can be easily recovered. The new hybrids are stable up to 300 degrees C and display a broad emission band under UV excitation assigned to oxygen-related defects at the silica particles surface. Emission color can be tuned by changing the excitation wavelength.

Antimicrobial resistance of isolated Streptococcus pneumoniae in a hospital of the Brazilian public system

Streptococcus pneumoniae is the predominant bacterial agent that affects the human population with pneumonia. This disease is an important cause of death in the elderly and the children under five years old. In this study, 29 strains of invasive S. pneumoniae were isolated from 29 patients of pneumonia, bacteremia and meningitis in the laboratory of the Municipal Hospital in Paulinia, Brazil, from May 2006 to October 2007. Patients' age ranged from 8 months old to 60 years old. These strains of S. pneumoniae were isolated from blood, pleural fluid and cerebrospinal fluid (CSF) of patients. After typing of encapsulated strains of S. pneumoniae through quellung reaction, their resistance to antimicrobial agents was gauged through Disc Diffusion Technique followed by determination of minimum inhibitory concentration (MIC). Among the 29 strains analyzed, 23 were methicillin-sensitive and six were methicillin-resistant and penicillin intermediate resistant. No strain presented full resistance to penicillin. Serotyping was performed only in two samples, which belonged to serotype 18. Our data may alert ambulatory regarding the incidence of pneumococcal strains resistant to the most common drugs due to inappropriate use of antimicrobials and also collaborate to the elaboration of pneumococcal conjugate vaccines specific to each region.

Determinantes morfológicos de prognóstico em pneumonia nosocomial: um estudo em autópsias

OBJETIVO: Determinar a prevalência de pneumonia nosocomial nas autópsias em um hospital público universitário; identificar os fatores de risco relacionados à pneumonia nosocomial e os potenciais fatores prognósticos relacionados à ocorrência de pneumonia nosocomial fatal; e correlacionar os achados anatomopatológicos com a ocorrência de pneumonia nosocomial e/ou pneumonia aspirativa. MÉTODOS: Estudo retrospectivo de 199 pacientes autopsiados, maiores de 1 ano de idade, internados no Hospital das Clínicas da Faculdade de Medicina de Botucatu da Universidade Estadual Paulista entre 1999 e 2006, cuja causa de morte (causa básica ou associada) foi pneumonia nosocomial. Testou-se a associação dos dados demográficos, clínicos e anatomopatológicos com os desfechos pneumonia nosocomial fatal e pneumonia aspirativa fatal. As variáveis significativas entraram na análise multivariada. RESULTADOS: A idade média foi de 59 ± 19 anos. A prevalência de pneumonia nosocomial em autópsias foi 29%, e essa foi a causa mortis de 22,6% dos pacientes autopsiados. A pneumonia nosocomial fatal correlacionou-se com os achados anatomopatológicos de alterações estruturais tabágicas (OR = 3,23; IC95%: 1,26-2,95; p = 0,02) e acometimento pulmonar bilateral (OR = 3,23; IC95%: 1,26-8,30; p = 0,01). Não houve associações significativas entre as variáveis e pneumonia aspirativa fatal. CONCLUSÕES: em nossa amostra, a pneumonia nosocomial teve prevalência elevada e foi responsável por quase 25% das mortes. A mortalidade é favorecida por alterações estruturais tabágicas e pneumonia bilateral. Esses achados corroboram os resultados de diversos estudos clínicos sobre pneumonia nosocomial.

Occurrence of pneumocystis pneumonia in HIV-infected patients and the interference of the highly active antiretroviral therapy

From the beginning of the AIDS epidemic, pneumocystis pneumonia ( PCP) has been distinguished as one of the most frequent opportunistic diseases with high morbid-mortality. As from 1996, the advent of the highly active antiretroviral therapy ( HAART) has changed the characteristics of such epidemic by reducing its related diseases and, as a result, AIDS-related mortality. With the purpose to estimate PCP occurrence and HAART interference, 376 HIV-infected or AIDS patients were studied from January 1992 to December 2002. Among them, 58 ( 15.5%) PCP cases were found. There was a higher occurrence of PCP in the group of patients in which HAART was not used, with 40 ( 69.0%) of the episodes. As regards the studied period, a tendency to a linear reduction in annual PCP incidence was observed. The mean of T CD4+ lymphocytes in the patients with PCP ( 117 cells/mm(3)) was significantly lower when compared to that of the other individuals ( 325 cells/mm(3)). Therefore, this study suggests a temporal reduction in PCP occurrence related to HAART use with higher T CD4+ lymphocyte counts. Nevertheless, this opportunistic infection still shows significant incidence in AIDS patients. ( NCT00516581).

Risk factors for Hospital-Acquired Pneumonia in nonventilated adults

Although most recent publications focus on Ventilator-associated Pneumonia, Non-Ventilator-associated Hospital-acquired pneumonia (NVHAP) is still worrisome. We studied risk factors for NVHAP among patients admitted to a small teaching hospital. Sixty-six NVHAP case patients and 66 controls admitted to the hospital from November 2005 through November 2006 were enrolled in a case-control study. Variables under investigation included: demographic characteristics, comorbidities, procedures, invasive devices and use of medications (Sedatives, Antacids, Steroids and Antimicrobials). Univariate and multivariable analysis (hierarchical models of logistic regression) were performed. The incidence of NVHAP in our hospital was 0.68% (1.02 per 1,000 patients-day). Results from multivariable analysis identified risk factors for NVHAP: age (Odds Ratio[OR]=1.03, 95% Confidence Interval[CI]=1.01-1.05, p=0.002), use of Antacids (OR=5.29, 95%CI=1.89-4.79, p=0.001) and Central Nervous System disease (OR=3.13, 95%CI=1.24-7.93, p=0.02). Although our findings are coherent with previous reports, the association of Antacids with NVHAP recalls a controversial issue in the physiopathology of Hospital-Acquired Pneumonia, with possible implications for preventive strategies.

Correlation of Atopobium vaginae Amount With Bacterial Vaginosis Markers

Objective. The purpose of this study was to test the correlation of the amount of Atopobium vaginae with the most commonly used markers for bacterial vaginosis (BV).Materials and Methods. We enrolled 103 nonpregnant and premenopausal women that were positive for BV by Amsel criteria and with a Nugent score higher than 3. All women were negative for yeast, Chlamydia trachomatis, Trichomonas vaginalis, and Neisseria gonorrhoeae. A. vaginae concentration was determined by quantitative polymerase chain reaction from samples of vaginal rinsings with 2 mL of sterile saline.Results. There was no difference in the median values of A. vaginae concentration when comparing samples with presence or absence of each individual Amsel criterion. In the case of a higher pH cutoff value of 4.9, greater amounts of this microorganism (p = .02) were found. In addition, correlation tests showed that A. vaginae concentration is positively correlated with pH (p < .001) and with Nugent scores (p = .003).Conclusions. The quantification of A. vaginae is useful for identification of the most severe cases of BV.

Acute bacterial cystitis does not cause deoxyribonucleic acid damage detectable by the alkaline comet assay in urothelial cells of dogs

Considering the high incidence of dogs with acute bacterial cystitis (BC) and the relationship among inflammation, genotoxicity, and carcinogenesis, we conducted a case-control study comparing the frequency of deoxyribonucleic acid (DNA) lesions assessed by the comet assay between disease-free animals (13 males and 13 females) and cytology-confirmed cases of acute BC (12 males and 12 females), which was mainly caused by Staphylococcus sp. (40%) and Escherichia coli (35%). The results show no increase in DNA damage in cells obtained by bladder washings and no influence of age, sex, and breed due to acute BC. In conclusion, DNA damage was seemingly not associated with the infection by specific bacteria.

Antibacterial effects of Brazilian and Bulgarian propolis and synergistic effects with antibiotics acting on the bacterial DNA and folic acid

Propolis is a honeybee product that has been used since ancient times because of its therapeutic effects. It can be used in the development of alternative therapies for the treatment of many diseases, and because propolis shows antibacterial action, this work was carried out in order to investigate a possible synergism between propolis and antibiotics acting on DNA (ciprofloxacin and norfloxacin) and on the metabolism (cotrimoxazole) against Salmonella Typhi. Propolis samples collected in Brazil and Bulgaria were compared in these assays, and the synergism was investigated by using 1/2 and 1/4 of the minimal inhibitory concentration for propolis and antibiotics, evaluating the number of viable cells according to the incubation time. Brazilian and Bulgarian propolis showed antibacterial activity, but no synergistic effects with the three tested antibiotics were seen. Previous works by our laboratory have revealed that propolis has synergistic effects with antibiotics, acting on the bacterial wall and ribosome, but it does not seem to interact with antibiotics acting on DNA or folic acid, and only a bacteriostatic action was seen in these assay conditions.

Use of prebiotics and probiotics of bacterial and yeast origin for free-range broiler chickens

This study aimed to evaluate the effects of probiotics and prebiotics of bacterial and yeast origin on the performance, development of the digestive system, carcass yield and meat quality of free-range broiler chickens. Five hundred and sixty male chicks of the strain ISA S757-N were reared from one to 84 days old. The birds were distributed in four treatments according to a completely randomized block design: T1 = Control, T2 = Probiotics and Prebiotics of bacterial origin, T3 = Probiotics and prebiotics of yeast origin, T4 = Probiotics and prebiotics of bacterial origin + probiotics and prebiotics of yeast origin. There were four repetitions with 35 birds per repetition, and the birds had access to a pasture area after 35 days of age. Characteristics evaluated were performance, development of the digestive system, carcass and parts yield, abdominal fat, breast meat physical measurements (length, width and height) and meat quality parameters (pH from breast and leg meat, cooking loss and shearing force from breast meat). Lower mortality (p<0.05) and higher weight gain from 64 to 77 and 64 to 84 days of age were seen in birds supplemented with probiotics and prebiotics of bacterial origin compared to the non-supplemented birds (control). There were significant differences (p<0.05) among treatments for carcass yield. Birds supplemented with both probiotics and prebiotics of microbial and yeast origin (T4) showed higher carcass yield than control birds. Supplementation with probiotics and prebiotics of bacterial origin (T2) or the supplementation of these together with those of yeast origin (T4) reduced mortality and increased the carcass yield in free-range broiler chickens.

Vaccination protocol and bacterial strain affect the serological response of beef calves against blackleg

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Antigenic Activity of Bacterial Endodontic Contents from Primary Root Canal Infection with Periapical Lesions against Macrophage in the Release of Interleukin-1 beta and Tumor Necrosis Factor alpha

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Characterization and in vitro evaluation of bacterial cellulose membranes functionalized with osteogenic growth peptide for bone tissue engineering

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)