Isolation, Characterization, and Antimicrobial Activity of Bacterial and Fungal Representatives Associated With Particulate Matter During Haze and Non-haze Days

Particulate matter (PM) has been a threat to the environment and public health in the metropolises of developing industrial countries such as Beijing. The microorganisms associated with PM have an impact on human health if they are exposed to the respiratory tract persistently. There are few reports on the microbial resources collected from PM and their antimicrobial activities. In this study, we greatly expanded the diversity of available commensal organisms by collecting 1,258 bacterial and 456 fungal isolates from 63 PM samples. A total of 77 bacterial genera and 35 fungal genera were included in our pure cultures, with Bacillus as the most prevalent cultured bacterial genus, Aspergillus, and Penicillium as the most prevalent fungal ones. During heavy-haze days, the numbers of colony-forming units (CFUs) and isolates of bacteria and fungi were decreased. Bacillus, Paenibacillus, and Chaetomium were found to be enriched during haze days, while Kocuria, Microbacterium, and Penicillium were found to be enriched during non-haze days. Antimicrobial activity against common pathogens have been found in 40 bacterial representatives and 1 fungal representative. The collection of airborne strains will provide a basis to greatly increase our understanding of the relationship between bacteria and fungi associated with PM and human health.

In vitro Time Kill of Trimethoprim/Sulfamethoxazole against Stenotrophomonas maltophilia versus Escherichia coli using Cation Adjusted Muller Hinton Broth and ISO-Sensitest Broth

Trimethoprim/sulfamethoxazole (TMP/SMZ) is considered the treatment of choice for infections caused by Stenotrophomonas maltophilia , but limited pharmacodynamic data are available to support current susceptibility breakpoints or guide optimal dosing. Time-kill studies using a TMP/SMZ concentration of 4/40 μg/mL were conducted to compare 4 S. maltophilia with 4 Escherichia coli having the same MICs (0.25/4.75-4/76 μg/mL) in cation adjusted Mueller Hinton Broth (CAMHB) and ISO-Sensitest™ broth (ISO). With the exception of the resistant isolates (4/76 μg/mL), which resulted in regrowth approaching control, TMP/SMZ displayed significantly greater killing for E. coli compared with S. maltophilia at each MIC. Against E. coli , mean changes at 24 hour were -4.49, -1.73, -1.59, and +1.83 log 10 colony forming units (CFU) for isolates with MICs of 0.25/4.75, 1/19, 2/39, and 4/74 μg/mL, respectively. The f AUC/MIC required for stasis, 1-log 10 , and 2-log 10 CFU reductions were 40.7, 59.5, and 86.3, respectively. In contrast, TMP/SMZ displayed no stasis or CFU reductions against any S. maltophilia regardless of MIC, and no pharmacodynamic thresholds were quantifiable. Observations were consistent in both CAMHB and ISO broth. These data add increasing evidence that current TMP/SMZ susceptibility breakpoints against S. maltophilia should be reassessed.

Antibacterial activity in three Chaetoceros microalgae species cultures by using antibiotics

Diatoms, such as Chaetoceros, grow in a mutualistic relationship with bacteria. However, in some cases, it is necessary to grow them in bacteria-free cultures. To reduce bacterial load, antibiotics are used, and on certain occasions it is necessary to use a mixture with more than one antibiotic. This work aimed to obtain a quick and effective protocol to reduce the bacterial load and evaluate the response of three Chaetoceros species with aquacultural importance. Single and mix antibiotics were used. Microalgal and bacterial growth was measured. The growth parameters for diatoms showed that the significantly highest cell concentration was for C. muelleri (3.15 x106 cells mL-1) and the lowest values to C. calcitrans (2.98 x106 cells mL-1). The significantly highest growth rate was for C. calcitrans (0.77 divisions per day), and the lowest values for Chaetoceros sp. (0.60 divisions per day). The growth parameters for heterotrophic bacteria showed that the significantly highest bacterial load was for Chaetoceros sp. (19.16 x106 CFU (Colony-Forming Units) mL-1) and the lowest values were for C. calcitrans (12.23 x106 CFU mL-1). The growth rate of the heterotrophic bacteria present in Chaetoceros cultures was similar among the three studied species. Streptomycin® and sulfate G41® produced a partial reduction of bacterial load. The most effective treatment for all three species was the use of an antibiotic mix composed of ampicillin® (250 μg mL-1), kanamycin® (200 μg mL-1), neomycin® (50 μg mL-1), and streptomycin® (100 μg mL-1) for three days. The mix prepared with the highest antibiotic concentration produced a reduction of bacteria (100%) for three days; however, it also induced a significant reduction of the growth of the three Chaetoceros species.

Impact of the Sanitation Regime on Production Safety of Paff Pastry in the Food Processing Plant

Food is essential for a person's life, it is a source of energy and substances that enable the activity of all his organs. However, food is also a biological substance, which itself is subject to certain changes, sometimes targeted in their production or cooking, sometimes undesirable changes due to the activity of certain food components or the action of microorganisms.The primary role of each food processing plant should be to ensure daily proper cleaning and sanitation, thus ensuring perfect hygiene of the premises in operation due to the prevention of foodborne diseases. Based on the results obtained in our study, we can concluce that the sanitation regime in the evaluated premises of paff pastry production is at a good level and the disinfection in the production of puff pastry is effective. Aspiral Persteril 15 disinfectant at 0.4 % concentration and time exposure of 30 minutes was effective on all evaluated surfaces in individual monitored parts of production with the exception of puff pastry production part, where we recorded on technology, specifically on slicing knife 35 CFU (colony forming units) of total count of bacteria and 3 CFU of coliform bacteria after disinfection. The situation did not improve even until the begining of production, the total count of bacteria increase to 45 CFU and coliform bacteria to 4 CFU.

Sanitation at the Slaughterhouse and the Hygiene of Food of Animal Origin

Nowdays, one of the most important issues is the issue of food safety. There are many problems with the control of food safety and creation of appropriate legislation that protects food of animal origin. Hygiene and sanitation should be effectively applied and should be controlled at each step during production in food processing plants. The aim of study was to evaluate the surface microorganisms in the monitored parts of the slaughterhouse before slaughter and during slaughter but also after disinfection by disinfectant Virkon S. Disinfectant was used in a 1 % concentration and applied by spraying. Virkon S was effective on all monitored surfaces except the table for organs, where were detected 2x102 colony forming units per 10 cm2 of total count of bacteria, 2x102 colony forming units per 10cm2 of coliform bacteria and 1x102 colony forming unit per 10cm2 of moulds after disinfection. The sanitation program should be thoroughly planned, actively enforced, and effectively supervised. Disinfection has its meaning since, everything that comes into contact with the raw material can contribute to outbreaks of food borne illness.

Relação Gênero Candida e Afecções Respiratórias em Pacientes Pediátricos / Candida Gender Relationship and Respiratory Diseases in Pediatric Patients

Resumo: O objetivo foi detectar fatores de risco associados à colonização por Candida na cavidade oral de pacientes pediátricos, com diagnóstico de afecção respiratória, em Hospital Universitário em virtude de enfermidade cujo diagnóstico se enquadrasse no Capítulo X da CID-10. Método: foram coletadas amostras de saliva de 31 crianças com auxílio de swab estéril e encaminhadas para processamento no laboratório de Microbiologia da Universidade Federal de Campina Grande, campus Cajazeiras, onde foram semeadas em Agar Sabouraud Dextrose com cloranfenicol e, em seguida, foram incubadas a 35°C±2/ 24h e mais 2 dias à temperatura ambiente para verificação de crescimento de unidades formadoras de colônia por mililitro (UFC.mL-1). Resultado: A taxa de colonização oral por Candida entre os pacientes submetidos à coleta foi de 25,8%, destes, 50% pertencentes à espécie Candida albicans. Conclusão: os dados do presente estudo refletem achados amplamente divulgados, como a relação inversa entre a colonização oral e a idade do paciente e a prevalência da espécie C. albicans. Ressalta ainda a relevância da relação entre o estado imunológico do paciente e a susceptibilidade deste à colonização por tais agentes. Palavras-chave: Candida spp; infecção hospitalar; criança. Abstract: To detect risk factors associated with Candida colonization in the oral cavity of pediatric patients diagnosed with respiratory disease at a University Hospital due to a disease whose diagnosis falls under Chapter X of the ICD-10. Method: Saliva samples were collected from 31 children with the aid of a sterile swab and sent for processing in the Microbiology laboratory of the Federal University of Campina Grande, campus Cajazeiras, where they were seeded in Agar Sabouraud Dextrose with chloramphenicol and then incubated to 35°C±2/ 24h plus 2 days at room temperature to verify the growth of colony forming units per milliliter (CFU.mL-1). Results: The rate of oral colonization by Candida among patients submitted to collection was 25.8%, of which 50% belonged to the Candida albicans species. Conclusion: the data from this study reflect widely publicized findings, such as the inverse relationship between oral colonization and patient age and the prevalence of the species C. albicans. It also emphasizes the relevance of the relationship between the patient's immune status and their susceptibility to colonization by such agents. Keywords: Candida spp; hospital infection; child.

Effect of Different Instrumentation and Irrigation Methods on Apical Microbial Extrusion: An Ex Vivo Study

Background: Periapical extrusion of debris, irrigating solution and microorganism are the major contributing factors for flare-ups during root canal therapy. The aim of this ex vivo study was to evaluate the effect of different types of instrumentation in combination with different irrigation methods on apical bacterial expulsion. Material and Methods: Three hundred and ten extracted human permanent teeth were infected with Enterococcus faecalis. After incubation at 37°C for 24 h, three hundred teeth were instrumented with three different instrumentations using two irrigation methods. The remaining ten teeth were used as negative and positive control groups, in which no inoculation was done and no instrumentation was carried out respectively. Three hundred teeth were equally divided in three groups (n = 100), in which instrumentation was performed using a protaper universal rotary file (group 1), WaveOne reciprocating file (group 2) and a flexiCON rotary file (group 3). In each group, 50 samples were irrigated with conventional needle irrigation, and 50 samples were irrigated with the endoVac irrigation method. During instrumentation, apically extruded bacteria were collected in an Eppendorf tube. Microbiological samples were taken from the Eppendorf tube and incubated for 24h, and colony-forming units were counted. The data collected were statistically analysed. Results: The group 2 showed highest bacterial extrusion using conventional irrigation while group 3 showed lowest using endovac irrigation system. Conclusion: FlexiCON rotary instrumentation with the endoVac irrigation system produced significantly less bacterial extrusion than the other techniques.

Comparison of Urine Flow Cytometry on the UF-1000i System and Urine Culture of Urine Samples from Urological Patients

<b><i>Introduction:</i></b> The aims of this study were to evaluate urine flow cytometry (UFC) as a tool to screen urine samples of urological patients for bacteriuria and to compare UFC and dipstick analysis with urine culture in a patient cohort at a urological department of a university hospital. <b><i>Methods and Material:</i></b> We screened 662 urine samples from urological patients (75.2% male; 80.7% inpatients; mean age 58 years). UFC results were compared to microbiological urine culture. <b><i>Results:</i></b> The accuracy in using the UFC-based parameters for detecting cultural bacteriuria was 91.99% and 88.97% for ≥10⁵ colony-forming units (CFU)/mL and ≥10⁴ CFU/mL, respectively. UFC and leukocyte dipstick analysis measured leukocyturia similarly (Pearson correlation coefficient 0.87, <i>p</i> value &#x3c;0.01%), but dipstick analysis scored less accurately on bacteriuria (accuracy 59.37% and 62.69%). UFC remained effective in subgroup analysis of patients of both sexes and with different urological conditions with its overall use only slightly impaired when assessing gross hematuria (NPV 84.62% for ≥10⁴ CFU/mL). UFC also reliably removed those urine samples below cutoffs with negative predictive values of 99.28% for ≥10⁵ CFU/mL and 95.86% for ≥10⁴ CFU/mL. <b><i>Conclusion:</i></b> Counting bacteria with UFC is an accurate and rapid method to determine significant bacteriuria in urological patients and is superior to dipstick analysis or indirect surrogate parameters such as leukocyturia. When UFC is available, we recommend it to be used for the diagnosis of bacteriuria over findings obtained by dipstick analysis.

Microbial contamination of hands with or without the use of bidet toilets (electric toilet seats with water spray) after defecation

Bidet toilets (electric toilet seats with water spray) are increasing in popularity worldwide. However, the extent of reduction of microbial contamination of the hands with the use of bidet toilets after defecation is unclear. Microbe contamination of the hands with and without the use of bidet toilets after defecation was examined in 32 nursing students. Double gloves were worn on the dominant hand and four layers of toilet paper were used to wipe the buttocks after defecation, and microbe contamination of the second glove (outer glove) of the double gloves was examined. The volunteers were free to select the flow volume, wash time of the bidet, and the type of bidet. Without the use of a bidet toilet, the average value ± standard deviation of the number of microbes attached to the gloves was 39,499.3 ± 77,768.3 colony forming units (cfu)/glove; however, it was 4,146.9 ± 11,427.7 cfu/glove when the bidet toilet was used. The number of microbes adhering to gloves was significantly reduced when a bidet toilet was used (p &lt; 0.00001, Wilcoxon signed-rank test).

Combination of Mycobacterium tuberculosis RS ratio and CFU improves the ability of murine efficacy experiments to distinguish between drug treatments

Murine tuberculosis drug efficacy studies have historically monitored bacterial burden based on colony forming units of M. tuberculosis in lung homogenate. In an alternative approach, a recently described molecular pharmacodynamic marker called the RS ratio quantifies drug effect on a fundamental cellular process: ongoing ribosomal RNA synthesis. Here we evaluated the ability of different pharmacodynamic markers to distinguish between treatments in three BALB/c mouse experiments at two institutions. We confirmed that different pharmacodynamic markers measure distinct biological responses. We found that a combination of pharmacodynamic markers distinguishes between treatments better than any single marker. The combination of the RS ratio with colony forming units showed the greatest ability to recapitulate the rank order of regimen treatment-shortening activity, providing proof of concept that simultaneous assessment of pharmacodynamic markers measuring different properties will enhance insight gained from animal models and accelerate development of new combination regimens. These results suggest potential for a new era in which antimicrobial therapies are evaluated not only on culture-based measures of bacterial burden but also on molecular assays that indicate how drugs impact the physiological state of the pathogen.