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1
Jarząb, Natalia, and Maciej Walczak. "The presence of biofilm forming microorganisms on hydrotherapy equipment and facilities." Journal of Water and Health 15, no. 6 (2017): 923–31. http://dx.doi.org/10.2166/wh.2017.025.
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Abstract Hydrotherapy equipment provides a perfect environment for the formation and growth of microbial biofilms. Biofilms may reduce the microbiological cleanliness of hydrotherapy equipment and harbour opportunistic pathogens and pathogenic bacteria. The aims of this study were to investigate the ability of microorganisms that colonize hydrotherapy equipment to form biofilms, and to assess the influence of temperature and nutrients on the rate of biofilm formation. Surface swab samples were collected from the whirlpool baths, inhalation equipment and submerged surfaces of a brine pool at the spa center in Ciechocinek, Poland. We isolated and identified microorganisms from the swab samples and measured their ability to form biofilms. Biofilm formation was observed at a range of temperatures, in both nutrient-deficient and nutrient-rich environments. We isolated and identified microorganisms which are known to form biofilms on medical devices (e.g. Stenotrophomonas maltophilia). All isolates were classified as opportunistic pathogens, which can cause infections in humans with weakened immunity systems. All isolates showed the ability to form biofilms in the laboratory conditions. The potential for biofilm formation was higher in the presence of added nutrients. In addition, the hydrolytic activity of the biofilm was connected with the presence of nutrients.
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Nosenko, O. M. "A modern view on cervicovaginal dysbiosis caused by bacterial vaginosis asocated bacteria and yeast-like fungi of the genus Candida (Literature review and own data)." HEALTH OF WOMAN, no. 7(153) (September 29, 2020): 74–83. http://dx.doi.org/10.15574/hw.2020.153.74.
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The article presents modern literature data on the definition and etiopathogenesis of cervicovaginal dysbiosis caused by opportunistic microflora, as well as own data of a comparative study of the effectiveness of treatment of symptomatic cervicovaginal dysbiosis caused by a combination of bacterial vaginosis associated microorganisms and fungi of the genus Candida, using combined drugs containing ternidazole, neomycin, nystatin and prednisolone Na-metasulfobenzoate salt (Terzhinan®) or metronidazole and miconazole. The objective: comparing the effectiveness of treatment of symptomatic cervicovaginal dysbiosis caused by a combination of vaginally associated microorganisms and fungi of the genus Candida, using combined drugs containing ternidazole, neomycin, nystatin and salts of Na-metasulfonobenzoate prednisolone or metoconazole. Materials and methods. The study included 107 women of reproductive age with symptomatic mixed cervicovaginal dysbiosis caused by a combination of bacterial vaginosis associated microorganisms and fungi of the genus Candida, and 30 conditionally gynecologically and somatically healthy control subjects with cervicovaginal eubiosis. Blindly examined women with cervicovaginal dysbiosis were divided into two groups: the main group – 56 patients treated with intravaginal tablets Terzhinan®, the comparison group – 51 women who used vaginal suppositories containing metronidazole and miconazole. The dynamics of clinical data and the state of the cervicovaginal microbiota were evaluated by PCR before the start, one and three months after the end of treatment. Results. An open comparative analysis showed that with topical therapy with Terzhinan® vaginal tablets a month after the end of treatment, a positive clinical effect was observed in 89.29% of women and a microbiological effect in 91.07% of patients, after three months – in 85.71% and in 89.29% of patients, respectively, whereas with topical therapy with vaginal suppositories containing 750 mg of metronidazole and 200 mg of miconazole, respectively, one month after the end of treatment – in 68.73% and 72.55% of cases and after three months – in 62, 75% and 66.67% of cases. Conclusion. Topical monotherapy with Terzhinan® vaginal tablets in comparison with vaginal suppositories containing metronidazole and miconazole demonstrates the clinical and microbiological advantages of Terzhinan® in the treatment of cervicovaginal dysbiosis caused by bacterial vaginosis associated microflora and yeast-like fungi of the genus Candida. Keywords: cervicovaginal microbiota, cervicovaginal dysbiosis, opportunistic microorganisms, bacterial vaginosis associated microorganisms, yeast-like fungi of the genus Candida, Terzhinan®, vaginal suppositories with metronidazole and miconazole, clinical efficacy, microbiological efficacy, safety, long-term results.
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Sobsey, Mark D. "Inactivation of Health-Related Microorganisms in Water by Disinfection Processes." Water Science and Technology 21, no. 3 (1989): 179–95. http://dx.doi.org/10.2166/wst.1989.0098.
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The recent literature on disinfection of health-related microorganisms in water and wastewater is reviewed. There is now considerable evidence that traditional microbial indicators of water and wastewater quality, such as total and fecal coliform bacteria, are inadequate to predict the presence or disinfection responses of several important, newly recognized bacterial, viral and protozoan pathogens. This review emphasizes the response to disinfection of waterborne microbial pathogens and potential indicators of recent recognition and public health concern. These organisms include heterotrophic plate count (HPC) bacteria, frank and opportunistic bacterial pathogens, such as Campylobacter jejuni, Yersinia enterocolytica, non-tubercular mycobacteria, Legionella spp. and pseudomonads; coliphage indicators and enteric viral pathogens, such as hepatitis A virus, rotaviruses and Norwalk virus; and protozoan pathogens, such as Giardia lamblia, Cryptosporidium, and the free-living amoeba (e.g., Acanthamoeba spp. and Negleria spp.). The responses of these organisms to widely used, traditional disinfectants, such as free and combined chlorine, and to disinfectants of more recent interest, such as ozone, chlorine dioxide and ultraviolet light, are reviewed. This review also attempts to identify the variety of factors influencing disinfection efficiency, especially those that interfere with disinfection. It is apparent that traditional microbial indicators, such as total and fecal coliforms, are more sensitive to disinfection than such pathogens of recent concern as mycobacteria, enteric viruses and protozoan cysts. Therefore, efforts must be continued to find more reliable indicators of disinfection efficiency and microbial water quality and improved methods for water and wastewater disinfection.
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Donets, N. N., I. E. Sokolova, A. A. Moskalenko, A. L. Drobina та A. I. Vinnikov. "Моніторинг умовно-патогенних і патогенних мікроорганізмів у лікарняних відділеннях хірургічного профілю м. Дніпродзержинськ". Visnyk of Dnipropetrovsk University. Biology, medicine 4, № 1 (2013): 23–29. http://dx.doi.org/10.15421/021304.
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The paper presents monitoring results of the spread of opportunistic and pathogenic microorganisms in patients of surgical departments of the Dniprodzerzhynsk city hospital No 7. 1464 strains of bacteria isolated from biological material of the patients from January to December 2012 were studied. Relevant standard methods of research and data interpretation in accordance with the regulatory guidelines were used. The microorganisms’ sensitivity to antibiotics was determined by the disk diffusion method. Assessment of the resistance of isolated microorganisms to antibiotics was made with the software Whonet 5.1. At the first stage of investigation sampling biological material and inoculation in the culture medium were made. The discharges of wounds, throat, nose, ears, vagina and urethra, and also urine from patients of surgical departments were sampled for bacteriological analysis. The main substratum was 5% blood agar. There may additionally be used the selective growth media (yolk-salt agar, Endo, and Saburo). At the second stage we identify microorganisms with bacterioscopic, bacteriological and biochemical methods. Identifying microorganisms of the genus Staphylococcus was made by the reaction of lecithinase presence, plasma-coagulation reaction and the mannitol oxidation reaction. For the identification of bacteria of the family Streptococcaceae the growth pattern in 0.5% sugar medium was used. It was differentiated from bacteria of the genus Enterococcus by plating onto egg yolk agar base and milk with 0.1% methylene blue. Identification of bacteria of the Enterobacteriaceae family was made by studying their colonies on dense differential diagnostic media. Suspicious colonies were transferred on a combined medium for primary identification (Olkenitsky's medium). Then the biochemical signs of enterobacteria were studied in the minimum number of tests. The third phase of the study included the determination of the sensitivity of microorganisms to antibiotics. To do that, we use the disc diffusion method. The antibiogram tests of isolated bacterial strains used Mueller-Hinton agar. According to the data obtained we assign of microorganisms to certain category of sensitivity: sensitive, moderately resistant or resistant. Monitoring of prevalent microorganisms showed that 61% (893 of 1464) isolates were gram-positive bacteria, 696 strains of them are staphylococci. 477 of these are identified as S. aureus, representing 68.5% of all Staphylococcus. We found coagulase negative staphylococci in 192 patients, and the strains of S. haemolyticus are dominated. Strains of the family Streptococcaceae isolated from 197 patients. Among them the E. faecalis accounted for 66% of the total number of Streptococcus. Gram negative bacteria were presented by the families Enterobacteriaceae and Pseudomonaceae. Enterobacteriaceae accounted for 90.7% (518 of 571). E. coli plays the leading role and accounted for 42% of all Enterobacteriaceae. The strains of P. aeruginosa were identified in 53 patients. S. haemolyticus has played an important role as a pathogen as well as S. aureus. Its resistance to antibiotics is much higher than that of S. aureus. Although S. haemolyticus is opportunistic coagulase negative, it can be isolated from patients not only with chronic, but with acute infection. Thus nowadays the strains of S. haemolyticus gained high pathogenic and virulent properties.
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Pérez-Torralba, Concepción, María Ruiz-Olivares, Sara Sanbonmatsu-Gámez, Manuela Expósito-Ruíz, José María Navarro-Marí, and José Gutiérrez-Fernández. "Increased infections by herpes simplex virus type 1 and polymicrobials of the genital tract, in the general population of a Spanish middle city." Revista Española de Quimioterapia 34, no. 4 (2021): 320–29. http://dx.doi.org/10.37201/req/004.2021.
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Introduction. Infections by genitopathogens are a frequent reason for consultation in Primary Health Care and in the specialties of Infectious Diseases, Urology, Gynecology, and Dermatology. The most common causes are opportunistic microorganisms and responsible for sexually transmitted infections associated with unprotected sex. The objective is to determine the microorganisms that cause these infections in patients treated at the Hospital Universitario Virgen de las Nieves in Granada and Neisseria gonorrhoeae susceptibility to antibiotics. Material and methods. A transversal-descriptive and retrospective study was carried out, which included the results issued, between January 2018 and December 2019, in the Microbiology Laboratory from all the episodes studied using standardized working procedures. Results. The most frequently detected microorganisms were Gardnerella vaginalis (23.81%) followed by Candida spp. (20.9%), especially in females, and N. gonorrhoeae (11.36%) and Ureaplasma urealyticum (11.99%), in males. Many times, they were presented in combination. Regarding herpes simplex viruses, infection by both species had a similar prevalence (50%) in males, while type 1 was more prevalent (76.52%) in females. The most active antibiotics against N. gonorrhoeae were cefotaxime (98%) and cefixime (100%). Tetracycline (39.02%) a poorly active antibiotic. Conclusions. The most frequent pathogens corresponded to those that usually caused infections in females, although N. gonorrhoeae was the most frequent in males and mixed infections are not an accidental finding. HSV-1 infections were more frequent than HSV-2, confirming the trend of a change in the epidemiology of genital herpes.
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Gordynets, S., L. Charniauskaya, J. Yakhnovets, and T. Hovzun. "STUDYING THE ANTIMICROBIAL EFFECT OF DETERGENTS AND DISINFECTANTS ON THE MICROFLORA OF THE EGG SHELL SURFACE." Topical issues of processing of meat and milk raw materials, no. 14 (December 14, 2020): 248–57. http://dx.doi.org/10.47612/2220-8755-2019-14-248-257.
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The article presents the results of evaluating the antimicrobial effect of detergents and disinfectants on the microflora of the eggshell surface. Washing and disinfection of eggs was carried out by manual treatment by immersion in washing and disinfecting solutions and subsequent washing with brushes.
 For washing eggs, an alkaline detergent with a «Sanet BIO» disinfectant effect was used, and for disinfection, one of the four selected disinfectants belonging to different groups of drugs: «SUNWAY DES» disinfectant (peroxide), «Silversil Des»
 disinfectant (silver-containing), «Lanex» disinfectant (based on Quaternary ammonium compounds), and «Catelon 502» disinfectant (containing peracetic acid). It was found that the treatment of eggs in order to reduce the contamination of the surface of their shells with «SUNWAY DES», «Catelon 502» and «Lanex» disinfectants by hand washing confirmed their effectiveness and leads to the disinfection of the shell from opportunistic and pathogenic microorganisms, as well as reduces the overall microbial contamination. Sanitization of egg shells of edible hen eggs by hand washing with the use of «Silversil Des» disinfectant in the spent modes showed that this tool is not effective in disinfecting egg shells, since immediately after processing, Staphylococcus aureus, Salmonella s.p.p. and Listeria s.p.p. bacteria were found on their surface.
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Efremov, Aleksandr Alekseyevich, Irina Dement'yevna Zykova, Vera Aleksandrovna Senashova, Irina Dmitriyevna Grodnickaya, and Natal'ya Veniaminovna Pashenova. "ANTIMICROBIAL AND ANTIRADICAL ACTIVITY OF INDIVIDUAL FRACTIONS OF PINUS SIBIRICA DU TOUR AND ABIES SIBIRICA LEDEB., NATIVE TO THE SIBERIAN REGION." chemistry of plant raw material, no. 4 (December 21, 2020): 203–10. http://dx.doi.org/10.14258/jcprm.2020047505.
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By the method of exhaustive hydroparodistillation, essential oil was obtained from Siberian pine (Pinus sibirica Du Tour) and Siberian fir (Abies sibirica Ledeb.), growing on the territory of the Krasnoyarsk territory. Separate fractions of oil were obtained: the first one after 45 min from the beginning of distillation, the second – after 2 hours, the third – after 5 hours, the fourth-after 10 hours, the fifth fraction was collected after the end of hydrodistillation. The antimicrobial activity of separate fractions of essential oil of P. sibirica and A. sibirica was studied against strains of opportunistic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus 209p, Micrococcus luteus, Acinetobacter baumanii, Candida albicans. The performed studies showed that all the studied samples of essential oils showed either bactericidal or bacteriostatic activity against the strains of microorganisms taken in the experiment, except Pseudomonas aeruginosa. The type of activity displayed depended on the type of strain and sample of essential oil. It is noted that the sensitivity of the experimental strains to the components of the essential oils of P. sibirica and A. sibirica decreases during the transition from the first to the last fraction. We assume that, apparently, this is due to a decrease in the number of monoterpenes in the composition of oils.To study the antiradical activity, the reaction of essential oil components with a stable free 2,2-diphenyl-1-picrylhydrazyl radical was used. Antiradical activity of both whole essential oils of P. sibirica and A. sibirica and their separate fractions was established. There was an increase in antiradical activity with a decrease in the content of monoterpenes in the composition of essential oil.
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Efremov, Aleksandr Alekseyevich, Irina Dement'yevna Zykova, and Natal'ya Sergeyevna Korosteleva. "ANTIMICROBIAL AND ANTIRADICAL ACTIVITY OF INDIVIDUAL FRACTIONS OF ESSENTIAL OIL FROM SEEDS OF HERACLEUM DISSECTUM LEDEB. OF SIBERIAN REGION." chemistry of plant raw material, no. 2 (June 10, 2020): 79–85. http://dx.doi.org/10.14258/jcprm.2020027029.
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By the method of exhaustive hydroponically obtained essential oil from beans of Heracleum dissectum Ledeb., growing in the Krasnoyarsk region. Separate fractions of oil were obtained: the first after 45 minutes from the beginning of distillation, the second – after 2 hours, the third-after 5 hours, the fourth fraction was collected after the end of hydro-distillation. The component composition of both whole essential oil and its separate fractions was studied. The main components are octyl acetate (60.0%), octyl-2-methylpropanoate (10.2%), n-hexyl-2-methylbutanoate (9.0%). The main amount of octyl acetate (64.7%) is concentrated in the first fraction of the oil. The antimicrobial activity of various fractions of essential oil of borscht dissected against strains of opportunistic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus 209p, MRSA, Proteus vulgaris. It was found that, depending on the duration of isolation, the antimicrobial activity of essential oil fractions in relation to Staphylococcus aureus 209p, MRSA and Pseudomonas aeruginosa decreases, and in relation to Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris increases. The most pronounced inhibitory effect of the third and fourth fractions of essential oil against Klebsiella pneumonia. The antiradical activity of all studied samples of borscht essential oil dissected in reaction with stable free 2,2-diphenyl-1-picrylhydrazyl radical was established. The first fraction showed minimal antiradical activity (15.1%), the fourth – maximum (49.2%).
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Shifris, І. М., I. O. Dudar, V. F. Krot, et al. "ANTIMICROBIAL RESISTANCE OF GRAM POSITIVE BACTERIA ISOLATED LNPATLENTS WLTHCHRONLCKLDNEYDLSEASSTAGE5D: PREVALENCE AND OUTCOMES." Ukrainian Journal of Nephrology and Dialysis, no. 2(46) (April 24, 2015): 13–21. http://dx.doi.org/10.31450/ukrjnd.2(46).2015.02.
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Bacterial infections in chronic kidney disease stage VD (CKD VD st.)patients are associated with increased risk of hospitalization and death.
 
 The aim was to study of opportunistic pathogenic bacteria spectrum, their antibacterial resistance and the correlation between carriage and hospitalization and mortality rate in adult patients with CKD V D st.
 Materials and methods. This prospective cohort, open-label, randomized, two-phase study included 146 patients with CKD V D st., 118 of whom were treated by hemodialysis (HD) and 28 by peritoneal dialysis (PD). The microbiological screening was conducted in the first stage. The examined material was throat/nose swabs and wet smears from skin of dialysis access site. On the second stage all patients were randomized on two groups: the group 1 (n=61) included patients with identified MRSA / VRE colonization and group 2 (n=85) included patients with colonization of other strains of opportunistic pathogenic bacteria. The groups were representative according to gender, age, type of kidney affections and renal replacement therapy (RRT) modality. The microbiological examination consisted of inoculation of hard medium by examined material. The end points were total amount of hospitalization and death events evaluated for 24 months after randomization.
 Results. The colonization of some biotype of opportunistic pathogenic bacteria was established in 100% ofpatients. In total were isolated 347 strains of gram-positive bacteria: 284 and 63 in HD and PD patients, respectively. Without statistical significance approximately 20% of microorganism strains were resistant to 10 and more antibiotics according to dialysis modality. The MRSA colonization was identified in 49 (33.6%) patients (37/31.4% and 12/42.9% of HD u PD patients, respectively; p=0,246). The VRE colonization was established in 12 patients (10/8.5% and 2/7.1% of HD and PD patients, respectively; p=0.81).
 The 70 hospitalization episodes were recorded during monitoring period. The significant majority was established in group 1 of patients (39/64% vs. 31/36.5 %; %2 =10.733, p=0,001) irrespective ofRRTmodality. The specific share ofdead persons in group 1 was in three times more than such share in group 2 (9/14.8% vs. 4/4.7 %; %2=4.42, p= 0.0355). The relative risks of hospitalization and death in the presence of MRSA/VRE colonization increased in 1.75 (95% CI: 1.252.5) and 3.14(95% CI: 1.01-9.7) times.
 Conclusion. In this study was demonstrated that MRSA/VRE colonization in adult patients with CKD V D st. is a risk marker and a predictor of negative clinical prognosis. The RRT modality hadn’t significant effect on rate of negative consequences, particularly on rate of hospitalization and death in population of CKD V D st. patients.
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Vogt, Nadine A., Christian P. G. Stevens, David L. Pearl, Eduardo N. Taboada, and Claire M. Jardine. "Generalizability and comparability of prevalence estimates in the wild bird literature: methodological and epidemiological considerations." Animal Health Research Reviews 21, no. 1 (2020): 89–95. http://dx.doi.org/10.1017/s1466252320000043.
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AbstractWild birds have been the focus of a great deal of research investigating the epidemiology of zoonotic bacteria and antimicrobial resistance in the environment. While enteric pathogens (e.g. Campylobacter, Salmonella, and E. coli O157:H7) and antimicrobial resistant bacteria of public health importance have been isolated from a wide variety of wild bird species, there is a considerable variation in the measured prevalence of a given microorganism from different studies. This variation may often reflect differences in certain ecological and biological factors such as feeding habits and immune status. Variation in prevalence estimates may also reflect differences in sample collection and processing methods, along with a host of epidemiological inputs related to overall study design. Because the generalizability and comparability of prevalence estimates in the wild bird literature are constrained by their methodological and epidemiological underpinnings, understanding them is crucial to the accurate interpretation of prevalence estimates. The main purpose of this review is to examine methodological and epidemiological inputs to prevalence estimates in the wild bird literature that have a major bearing on their generalizability and comparability. The inputs examined here include sample type, microbiological methods, study design, bias, sample size, definitions of prevalence outcomes and parameters, and control of clustering. The issues raised in this review suggest, among other things, that future prevalence studies of wild birds should avoid opportunistic sampling when possible, as this places significant limitations on the generalizability of prevalence data.
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Harrison, Alistair, Estevan A. Santana, Blake R. Szelestey, David E. Newsom, Peter White, and Kevin M. Mason. "Ferric Uptake Regulator and Its Role in the Pathogenesis of Nontypeable Haemophilus influenzae." Infection and Immunity 81, no. 4 (2013): 1221–33. http://dx.doi.org/10.1128/iai.01227-12.
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ABSTRACTNontypeableHaemophilus influenzae(NTHi) is a commensal microorganism of the human nasopharynx, and yet is also an opportunistic pathogen of the upper and lower respiratory tracts. Host microenvironments influence gene expression patterns, likely critical for NTHi persistence. The host sequesters iron as a mechanism to control microbial growth, and yet iron limitation influences gene expression and subsequent production of proteins involved in iron homeostasis. Careful regulation of iron uptake, via theferricuptakeregulator Fur, is essential in multiple bacteria, including NTHi. We hypothesized therefore that Fur contributes to iron homeostasis in NTHi, is critical for bacterial persistence, and likely regulates expression of virulence factors. Toward this end,furwas deleted in the prototypic NTHi clinical isolate, 86-028NP, and we assessed gene expression regulated by Fur. As expected, expression of the majority of genes that encode proteins with predicted roles in iron utilization was repressed by Fur. However, 14 Fur-regulated genes encode proteins with no known function, and yet may contribute to iron utilization or other biological functions. In a mammalian model of human otitis media, we determined that Fur was critical for bacterial persistence, indicating an important role for Fur-mediated iron homeostasis in disease progression. These data provide a profile of genes regulated by Fur in NTHi and likely identify additional regulatory pathways involved in iron utilization. Identification of such pathways will increase our understanding of how this pathogen can persist within host microenvironments, as a common commensal and, importantly, as a pathogen with significant clinical impact.
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Schel, A. J., P. D. Marsh, D. J. Bradshaw, et al. "Comparison of the Efficacies of Disinfectants To Control Microbial Contamination in Dental Unit Water Systems in General Dental Practices across the European Union." Applied and Environmental Microbiology 72, no. 2 (2006): 1380–87. http://dx.doi.org/10.1128/aem.72.2.1380-1387.2006.
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ABSTRACT Water delivered by dental unit water systems (DUWS) in general dental practices can harbor high numbers of bacteria, including opportunistic pathogens. Biofilms on tubing within DUWS provide a reservoir for microorganisms and should be controlled. This study compared disinfection products for their ability to meet the American Dental Association's guideline of <200 CFU · ml−1 for DUWS water. Alpron, BioBlue, Dentosept, Oxygenal, Sanosil, Sterilex Ultra, and Ster4Spray were tested in DUWS (n = 134) in Denmark, Germany, Greece, Ireland, The Netherlands, Spain, and the United Kingdom. Weekly water samples were tested for total viable counts (TVCs) on yeast extract agar, and, where possible, the effects of products on established biofilm (TVCs) were measured. A 4- to 5-week baseline measurement period was followed by 6 to 8 weeks of disinfection (intermittent or continuous product application). DUWS water TVCs before disinfection ranged from 0 to 5.41 log CFU · ml−1. Disinfectants achieved reductions in the median water TVC ranging from 0.69 (Ster4Spray) to 3.11 (Dentosept) log CFU · ml−1, although occasional high values (up to 4.88 log CFU · ml−1) occurred with all products. Before treatment, 64% of all baseline samples exceeded American Dental Association guidelines, compared to only 17% following commencement of treatment; where tested, biofilm TVCs were reduced to below detectable levels. The antimicrobial efficacies of products varied (e.g., 91% of water samples from DUWS treated with Dentosept or Oxygenal met American Dental Association guidelines, compared to 60% of those treated with Ster4Spray). Overall, the continuously applied products performed better than those applied intermittently. The most effective products were Dentosept and Oxygenal, although Dentosept gave the most consistent and sustained antimicrobial effect over time.
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de Sousa Eduardo, Leticia, Ticiane Costa Farias, Siluana Benvindo Ferreira, Paula Benvindo Ferreira, Zilka Nanes Lima та Savio Benvindo Ferreira. "Antibacterial Activity and Time-kill Kinetics of Positive Enantiomer of α-pinene Against Strains of Staphylococcus aureus and Escherichia coli". Current Topics in Medicinal Chemistry 18, № 11 (2018): 917–24. http://dx.doi.org/10.2174/1568026618666180712093914.
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Research on new antimicrobial agents is needed, as more and more microorganisms that cause antibiotic-resistant diseases are emerging commercially. In this group, we can find strains of Staphylococcus aureus and Escherichia coli, which are highly opportunistic species. Faced with this perspective, research using essential oils present in plants is emerging as a therapeutic alternative for the treatment of antimicrobial infections. Many of these oils have, in their composition, monoterpene α-pinene, that shows to have antibacterial activity. The purpose of this research is to evaluate the antimicrobial activity of the positive enantiomer of α-pinene against strains of Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922. The methodologies used were: Disc-diffusion test, broth microdilution and bacterial death kinetics, all of which were standardized by CLSI. As a result, inhibition halos of 11 mm was obtained for the gram-positive strain and 12 mm for the gram-negative strain, both at the same concentration, 160 µl / ml. In addition, it was possible to observe with the death curve that the concentrations (1.25 µl/mL and 2.5 µl/mL of the (+)-α-pinene were able to eliminate the formation of bacterial colonies at one time of exposure of 2 hours for the E. coli strain. However, the death curve of the S. aureus strain was characterized by non-elimination of bacterial colonies at a 24 hours exposure time used for the experiment. Only amikacin evidenced its bacterial killing rate of all colonies within two hours of exposure. At the end, it was possible to verify the activity of the phytoconstituent against Escherichia coli strains ATCC 25922 and Staphylococcus aureus ATCC 25923, recommending the continuity of the studies with the use of different methodologies so that (+) - α-pinene in the future can be a compound used in antimicrobial therapy.
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Yang, Yong, Lyudmila Asyakina, Olga Babich, et al. "Physicochemical properties and biological activity of extracts of dried biomass of callus and suspension cells and in vitro root cultures." Food Processing: Techniques and Technology 50, no. 3 (2020): 480–92. http://dx.doi.org/10.21603/2074-9414-2020-3-480-492.
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Introduction. One of the urgent problems of medicine and biology is the use of plant objects as industrial producers of target metabolites in vitro. In vitro cells can be used as pharmaceutical preparations.
 Study objects and methods. The present research featured medicinal plants that grow in the Siberian Federal district and are a popular source of medicinal raw materials. The physicochemical properties, e.g. total ash content in extracts, the content of heavy metals, the content of organic solvents in the extracts, and the mass loss upon drying was determined by standard methods. The antimicrobial properties of in vitro extracts were determined by the diffusion method and the method based on optical density measurement. The list of opportunistic and pathogenic test strains included the following microorganisms: E. coli ATCC 25922, S. aureus ATCC 25923, P. vulgaris ATCC 63, P. aeruginosa ATCC 9027, and C. albicans EMTC 34. The number of viable cancer cells was determined using the MTT colorimetric method.
 Results and discussion. The paper describes the physicochemical properties, safety indicators, antioxidant activity, antimicrobial activity, and antitumor properties of extracts of a complex of biologically active substances obtained in vitro from the dried biomass of callus and suspension cell cultures and root cultures. The root extracts proved to have the maximum antimicrobial and cytotoxic properties. They could reduce the survival rate of cancer cells to 24.8–36.8 %.
 Conclusion. The research featured extracts obtained from the dried biomass of callus and suspension cell cultures and root cultures in vitro of safflower leuzea (Leuzea carthamoides L.), Rhodiola rosea (Rhodiola rosea L.), various sorts of skullcap (Scutellaria baicalensis L., Scutellaria andrachnoides L., Scutellaria galericulata L.), Potentilla alba (Potentilla alba L.) and ginseng (Panax L.). The results showed that the extracts can be used for the production of pharmaceuticals and biologically active additives with antitumor, antimicrobial, and antioxidant properties.
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Stepanova, Anna M., Nadezhda P. Tarabukina, Marfa P. Scryabina, Mikhail P. Neustroev, and Svetlana I. Parnikova. "Litter feed additive as source of amino acids and beneficial bacteria." RUDN Journal of Agronomy and Animal Industries 14, no. 4 (2019): 466–80. http://dx.doi.org/10.22363/2312-797x-2019-14-4-466-480.
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Feed additive was derived from poultry manure by microbiological synthesis. After a 10-day feeding poultry with probiotic strains of bacteria B. subtilis TNP-3 and B. subtilis TNP-5, the litter does not contain potential enteropathogens and can be used as a raw material for feed additive. Based on the results of microbiological and biochemical studies the technology of feed additive (powder) with the use of extrusion was developed. Extrusion at a temperature of up to 120 °C for 5-6 seconds provides presence of beneficial bacteria and significantly high content of essential amino acids. According to the results of biochemical studies, litter feed additive contains 18 free amino acids. The total concentration of free amino acids in the feed additive (powder) is 406.3 mg/kg, which is 1.7 times higher than that in the litter without fermentation and extrusion. The experiments have shown that inclusion of 3.3% feed additive in the diet does not have negative effect on physiological state, viability and productivity of laying hens. Survival of birds in both groups was 100%. Additive application in the experimental group of chickens revealed absence of opportunistic pathogenic microorganisms and microscopic fungi, presence of bifidobacteria and spore-forming aerobic Bacillus bacteria in powder, as well as predominance of beneficial micro flora and lack of potential enteropathogens (compared to control). It allows to conclude that feed additive obtained by microbiological synthesis from bird droppings possess probiotic properties. The results of biochemical study of egg production indicate that the use of food additives (to 3.3% of the basic diet) for laying hens significantly increases content of major micro and macro-elements in eggs, compared to the control. Therefore, the use of feed additive-powder (up to 3.3% of the basic diet) does not reduce egg quality. Thus, based on the results of these studies, it can be concluded that the litter obtained from laying hens, after application of probiotic ‘Nord-Bakt’, further fermentation with strains Bacillus subtilis TNP-3 and Bacillus subtilis TNP-5, followed by extrusion can be used as a feed additive as a source of amino acids and beneficial bacteria.
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Bazghaleh, Navid, Pratibha Prashar, Sheridan Woo, and Albert Vandenberg. "Effects of Lentil Genotype on the Colonization of Beneficial Trichoderma Species and Biocontrol of Aphanomyces Root Rot." Microorganisms 8, no. 9 (2020): 1290. http://dx.doi.org/10.3390/microorganisms8091290.
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Trichoderma species are opportunistic plant symbionts that are common in the root and rhizosphere ecosystems. Many Trichoderma species may enhance plant growth, nutrient acquisition, and disease resistance, and for these reasons, they are widely used in agriculture as biofertilizers or biocontrol agents. Host plant genotype and other microorganisms, such as root pathogens, may influence the efficacy of Trichoderma inoculants. Aphanomyces euteiches is an important soil-borne oomycete in western Canada that causes root rot in legume crops such as lentil and pea, and there is not yet any significantly resistant varieties or effective treatments available to control the disease. In this study, the composition of root-associated fungal communities and the abundance of Trichoderma species, T. harzianum strain T-22 and T. virens strain G41, was determined in the roots of eight Lens genotypes based on internal transcribed spacer (ITS) Illumina MiSeq paired-end sequencing, both in the presence and the absence of the root rot pathogen Aphanomyces euteiches. Biocontrol effects of T. harzianum on A. euteiches was also examined. Significant genotypic variations were observed in the composition of root-associated fungal communities and the abundance of the different Trichoderma species in the lentil roots. The presence of A. euteiches altered the composition of Trichoderma found associated to the lentil genotypes. Biocontrol of A. euteiches by T. harzianum T22 species was observed in vitro and positive correlations between the abundance of Trichoderma and plant root and shoot biomass were observed in vivo. These findings revealed that lentil genotype and infection by the phytopathogen A. euteiches greatly influenced the colonization of root-associated fungi and the abundance of the Trichoderma species, as well as the effect on plant growth promotion. The multipartite interactions observed among lentil genotypes, Trichoderma species and A. euteiches suggest possibilities to select compatible host-beneficial microbe combinations in lentil breeding programs and to develop application strategies to harness the beneficial effects of Trichoderma inoculants in sustainable crop production systems.
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Perry, Austin M., Aaron D. Hernday, and Clarissa J. Nobile. "Unraveling How Candida albicans Forms Sexual Biofilms." Journal of Fungi 6, no. 1 (2020): 14. http://dx.doi.org/10.3390/jof6010014.
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Biofilms, structured and densely packed communities of microbial cells attached to surfaces, are considered to be the natural growth state for a vast majority of microorganisms. The ability to form biofilms is an important virulence factor for most pathogens, including the opportunistic human fungal pathogen Candida albicans. C. albicans is one of the most prevalent fungal species of the human microbiota that asymptomatically colonizes healthy individuals. However, C. albicans can also cause severe and life-threatening infections when host conditions permit (e.g., through alterations in the host immune system, pH, and resident microbiota). Like many other pathogens, this ability to cause infections depends, in part, on the ability to form biofilms. Once formed, C. albicans biofilms are often resistant to antifungal agents and the host immune response, and can act as reservoirs to maintain persistent infections as well as to seed new infections in a host. The majority of C. albicans clinical isolates are heterozygous (a/α) at the mating type-like (MTL) locus, which defines Candida mating types, and are capable of forming robust biofilms when cultured in vitro. These “conventional” biofilms, formed by MTL-heterozygous (a/α) cells, have been the primary focus of C. albicans biofilm research to date. Recent work in the field, however, has uncovered novel mechanisms through which biofilms are generated by C. albicans cells that are homozygous or hemizygous (a/a, a/Δ, α/α, or α/Δ) at the MTL locus. In these studies, the addition of pheromones of the opposite mating type can induce the formation of specialized “sexual” biofilms, either through the addition of synthetic peptide pheromones to the culture, or in response to co-culturing of cells of the opposite mating types. Although sexual biofilms are generally less robust than conventional biofilms, they could serve as a protective niche to support genetic exchange between mating-competent cells, and thus may represent an adaptive mechanism to increase population diversity in dynamic environments. Although conventional and sexual biofilms appear functionally distinct, both types of biofilms are structurally similar, containing yeast, pseudohyphal, and hyphal cells surrounded by an extracellular matrix. Despite their structural similarities, conventional and sexual biofilms appear to be governed by distinct transcriptional networks and signaling pathways, suggesting that they may be adapted for, and responsive to, distinct environmental conditions. Here we review sexual biofilms and compare and contrast them to conventional biofilms of C. albicans.
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Rieder, Jessica, Adamantia Kapopoulou, Nicolas Zürcher, Claudia Bank, and Irene Adrian-Kalchhauser. "Bacteria Communities in Swiss Fish Farms with Recirculating Aquaculture Systems." ARPHA Conference Abstracts 4 (March 4, 2021). http://dx.doi.org/10.3897/aca.4.e65444.
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Recirculating aquaculture systems (RAS), often used in fish farming, rely on microorganisms to maintain healthy water quality, nutrient cycling, animal welfare, and disease control. However, many daily operations in fish farms (e.g., stocking) may negatively affect the microorganisms' community composition and create a favorable environment for opportunistic pathogens. Currently, understanding microorganisms' communities within RAS is scarce, which presents an obstacle for pro-active system management. To better understand microorganism communities' spatial and temporal structure within fish farms using a RAS, we collected samples of filtered water and biofilm swabs from two different Swiss fish farms and two different locations within each farm. Water was collected from within one tank and the biofilter, while biofilm swabs were collected from the same tank's wall where the water sample was collected. DNA was extracted using the Purelink Microbial DNA Purification kit, and then each sample was prepared with three different primer pairs, 341F/805R (V3V4 region), 515F/806R (V4), 27F/534R (V1-3), and ran on the MiSeq platform (v3 600 cycles). The pilot study aimed to understand 1) how the microbiota composition changes regarding spatial and temporal scales within and between farms, 2) the primer effect on detected taxa, and 3) the difference between commonly-used 16s pipelines.
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Čermáková, Jiřina, Jakub Mrázek, Kateřina Fliegerová, and Daniel Tenkrát. "Replacing Natural Gas by Biogas — Determining the Bacterial Contamination of Biogas by PCR." Acta Polytechnica 52, no. 4 (2012). http://dx.doi.org/10.14311/1582.
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A promising way of using biogas is to upgrade it to natural gas, which is referred to as Substitute Natural Gas (SNG) or biomethane. Biomethane, or biogas, is produced by biological processes of harnessing the ability of microorganisms to degrade organic material to methane. Some of the microorganisms are aerosolized from the digester into the biogas; afterwards a bio-film is formed that attaches to the surfaces of the distribution pipes, and can find it was to the place where the end use of biogas takes place. This paper deals with the detection of microbial species in biogas, their influenceon corrosion and the potential risk that diseases can be spread via biogas using molecular techniques. Using molecular methods, we found that raw biogas contains about 8 million microorganisms per m3, which is most likely the result of microbial transmission from the anaerobic digestion process. Some bacterial species may contribute to the corrosion of pipelines and equipment; others are opportunistic pathogens that can cause toxic reactions. However, most bacterial species, more than 40 % in biogas, are still unknown, as is their influence on the digestion process and on human health. Further studies are needed to better understand the behavior of microorganisms in anaerobic digestion and to preventmicrobial-influenced corrosion and microbial dissemination.
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Martins, Nathana Beatriz, Lucas Arthur Ricardo Ferreira, Caroline Lopes Queiroz, et al. "Caseous Stomatitis Caused by Pseudomonas aeruginosa in Boa constrictor amarali." Acta Scientiae Veterinariae 49 (March 12, 2021). http://dx.doi.org/10.22456/1679-9216.105257.
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Background: Pseudomonas aeruginosa is a bacterium that belongs to the microbiota of snakes, but it may also be an opportunistic pathogen and contaminate humans through fecal contact, bites, and injuries. In snakes, this microorganism may present high pathogenicity at certain conditions and have been associated with high morbidity and mortality. Reports of infection of Boa constrictor by this pathogen are rare. Thus, this study aimed to describe the P. aeruginosa oral infection in a snake specimen (Boa constrictor amarali), approaching the isolation and identification of the infectious agents involved, the antimicrobial sensitivity and resistance, and the therapeutic protocol adopted.Case: A free-living adult female specimen of Boa constrictor amarali (Amaral's boa), with no described previous history was rescued in an urban area by the Environmental Police. Clinical evaluations showed structures of caseous aspect in the oral cavity, with hyperemia spots in the mucosa. Samples of these lesions were sent for mycological examination, and fungal forms were not found. Samples were collected for isolation and culture. The antimicrobial susceptibility of the isolated microorganisms was determined by the modified Kirby-Bauer disk diffusion method. P. aeruginosa was isolated and showed susceptibility to amikacin, gentamicin, and polymyxin-B; intermediate susceptibility to azithromycin, and ciprofloxacin; and resistance to cephalexin, ceftiofur, chloramphenicol, and enrofloxacin. The treatment consisted of cleaning of the oral cavity, local infiltration of lidocaine for debridement of the caseous area that were later cauterized with iodine. Systemic antibiotic therapy was used, with intramuscular administration of amikacin (5 mg/kg) for the first dose and (2.5 mg/kg) for the other doses with intervals of 72 h, and oral administration of metronidazole (20 mg/kg) with intervals of 48 h, both during 21 days. Daily subcutaneous fluid therapy was performed as support treatment, using Lactated Ringer's solution (25 mg/kg) and Vitamin C (10 mg/kg) with intervals of 24 h, being the cure observed at the end of treatment.Discussion: This paper presents the pathological findings of the Pseudomonas aeruginosa oral infection in a B. constrictor amarali. This bacterium is an opportunistic pathogen that is commonly found in snakes, thus, humans in contact with these animals may be contaminated with this pathogen. However, oral cavity lesions associated with P. aeruginosa had not yet been related to Boa constrictor amarali, which is a non-venomous species. Few bacteria associated with reptile diseases are primary causative agents. Clinical bacterial infections generally tend to be secondary to viral infections. Predisposing factors for the development of bacterial diseases in these reptiles include immunodepression, malnutrition, poor adaptation to captivity, and the maintenance of these animals at temperatures and humidities outside their thermal comfort range. In the present study, the P. aeruginosa behaved as an opportunistic pathogen, resulting in clinical manifestations with caseous lesions in the oral cavity, probably due to an imbalance of the microbiota caused by stress or immunodepression. The antibiogram allowed the adoption of a correct therapeutic protocol based on the susceptibility of the pathogen, resulting in remission of lesions and clinical signs after 21 days of treatment.
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Veach, Allison M., Huaihai Chen, Zamin K. Yang, et al. "Plant Hosts Modify Belowground Microbial Community Response to Extreme Drought." mSystems 5, no. 3 (2020). http://dx.doi.org/10.1128/msystems.00092-20.
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ABSTRACT Drought stress negatively impacts microbial activity, but the magnitude of stress responses is likely dependent on a diversity of belowground interactions. Populus trichocarpa individuals and no-plant bulk soils were exposed to extended drought (∼0.03% gravimetric water content [GWC] after 12 days), rewet, and a 12-day “recovery” period to determine the effects of plant presence in mediating soil microbiome stability to water stress. Plant metabolomic analyses indicated that drought exposure increased host investment in C and N metabolic pathways (amino acids, fatty acids, phenolic glycosides) regardless of recovery. Several metabolites positively correlated with root-associated microbial alpha-diversity, but not those of soil communities. Soil bacterial community composition shifted with P. trichocarpa presence and with drought relative to irrigated controls, whereas soil fungal composition shifted only with plant presence. However, root fungal communities strongly shifted with drought, whereas root bacterial communities changed to a lesser degree. The proportion of bacterial water-stress opportunistic operational taxonomic units (OTUs) (enriched counts in drought) was high (∼11%) at the end of drying phases and maintained after rewet and recovery phases in bulk soils, but it declined over time in soils with plants present. For root fungi, opportunistic OTUs were high at the end of recovery in drought treatments (∼17% abundance), although relatively not responsive in soils, particularly planted soils (<0.5% abundance for sensitive or opportunistic). These data indicate that plants modulate soil and root-associated microbial drought responses via tight plant-microbe linkages during extreme drought scenarios, but trajectories after extreme drought vary with plant habitat and microbial functional groups. IMPORTANCE Climate change causes significant alterations in precipitation and temperature regimes that are predicted to become more extreme throughout the next century. Microorganisms are important members within ecosystems, and how they respond to these changing abiotic stressors has large implications for the functioning of ecosystems, the recycling of nutrients, and the health of the aboveground plant community. Drought stress negatively impacts microbial activity, but the magnitude of this stress response may be dependent on above- and belowground interactions. This study demonstrates that beneficial associations between plants and microbes can enhance tolerance to abiotic stress.
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"CANDIDA ALBICANS AND STAPHYLOCOCCUS AUREUS CO-INFECTION IN MICE AFTER ANTIBIOTIC-INDUCED DYSBIOSIS." Journal of V. N. Karazin Kharkiv National University, Series "Medicine", no. 36 (2018). http://dx.doi.org/10.26565/2313-6693-2018-36-03.
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Microbial interactions in Staphylococcus aureus–Candida albicans dual-species biofilms is a relevant research topic given the significant contribution of these microorganisms to hospital-acquired infections. Therefore, the purpose of our investigation was to study the interaction of opportunistic C. albicans and S. aureus in vivo and in vitro, both with the participation of normal microflora and in mice with antibacterial dysbiosis. The study of mentioned interactions was carried out on 100 white male mice weighing approximately 18 grams in vivo and using smears prepared from the grown mixed cultures of C. albicans and S. aureus and the Japan JEM 1400 transmission electron microscope for the purpose of electron microscopic study of microorganisms in vitro. Healthy mice forming control groups and mice with antibiotic-induced dysbiosis (after introduction of vancomycin, gentamicin, ampicillin) were divided into groups to create a mono- and associative infection: Ι group was given 1×107 CFU of C. albicans, II group – 1×108 CFU of S. aureus, and III group – a mixture of specified concentrations of C. albicans and S. aureus in the same proportion. Microorganisms causing monoinfection were being isolated from the body of animals treated with antibiotics till the end of the experiments in large quantities unlike in case of the healthy mice. Co-inoculation of these microbes in the same dose to animals (co-infection), which were injected with antibiotics, turned out to be fatal for them, whereas an adhesive bond was seen between the cells of C. albicans vs. S. aureus in vitro. As can be seen, such bacterial-fungal co-infection reduce substantially the effectiveness of antibiotic therapy and the likelihood of successful treatment and can not be ignored when choosing the appropriate treatment.
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Adewunmi, Yetunde, Sanchirmaa Namjilsuren, William D. Walker, et al. "Antimicrobial Activity of, and Cellular Pathways Targeted by, p-Anisaldehyde and Epigallocatechin Gallate in the Opportunistic Human Pathogen Pseudomonas aeruginosa." Applied and Environmental Microbiology 86, no. 4 (2019). http://dx.doi.org/10.1128/aem.02482-19.
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ABSTRACT Plant-derived aldehydes are constituents of essential oils that possess broad-spectrum antimicrobial activity and kill microorganisms without promoting resistance. In our previous study, we incorporated p-anisaldehyde from star anise into a polymer network called proantimicrobial networks via degradable acetals (PANDAs) and used it as a novel drug delivery platform. PANDAs released p-anisaldehyde upon a change in pH and humidity and controlled the growth of the multidrug-resistant pathogen Pseudomonas aeruginosa PAO1. In this study, we identified the cellular pathways targeted by p-anisaldehyde by generating 10,000 transposon mutants of PAO1 and screened them for hypersensitivity to p-anisaldehyde. To improve the antimicrobial efficacy of p-anisaldehyde, we combined it with epigallocatechin gallate (EGCG), a polyphenol from green tea, and demonstrated that it acts synergistically with p-anisaldehyde in killing P. aeruginosa. We then used transcriptome sequencing to profile the responses of P. aeruginosa to p-anisaldehyde, EGCG, and their combination. The exposure to p-anisaldehyde altered the expression of genes involved in modification of the cell envelope, membrane transport, drug efflux, energy metabolism, molybdenum cofactor biosynthesis, and the stress response. We also demonstrate that the addition of EGCG reversed many p-anisaldehyde-coping effects and induced oxidative stress. Our results provide insight into the antimicrobial activity of p-anisaldehyde and its interactions with EGCG and may aid in the rational identification of new synergistically acting combinations of plant metabolites. Our study also confirms the utility of the thiol-ene polymer platform for the sustained and effective delivery of hydrophobic and volatile antimicrobial compounds. IMPORTANCE Essential oils (EOs) are plant-derived products that have long been exploited for their antimicrobial activities in medicine, agriculture, and food preservation. EOs represent a promising alternative to conventional antibiotics due to their broad-range antimicrobial activity, low toxicity to human commensal bacteria, and capacity to kill microorganisms without promoting resistance. Despite the progress in the understanding of the biological activity of EOs, our understanding of many aspects of their mode of action remains inconclusive. The overarching aim of this work was to address these gaps by studying the molecular interactions between an antimicrobial plant aldehyde and the opportunistic human pathogen Pseudomonas aeruginosa. The results of this study identify the microbial genes and associated pathways involved in the response to antimicrobial phytoaldehydes and provide insights into the molecular mechanisms governing the synergistic effects of individual constituents within essential oils.
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Wilhelm, Roland C., Charles Pepe-Ranney, Pamela Weisenhorn, Mary Lipton, and Daniel H. Buckley. "Competitive Exclusion and Metabolic Dependency among Microorganisms Structure the Cellulose Economy of an Agricultural Soil." mBio 12, no. 1 (2021). http://dx.doi.org/10.1128/mbio.03099-20.
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ABSTRACT Microorganisms that degrade cellulose utilize extracellular reactions that yield free by-products which can promote interactions with noncellulolytic organisms. We hypothesized that these interactions determine the ecological and physiological traits governing the fate of cellulosic carbon (C) in soil. We performed comparative genomics with genome bins from a shotgun metagenomic-stable isotope probing experiment to characterize the attributes of cellulolytic and noncellulolytic taxa accessing 13C from cellulose. We hypothesized that cellulolytic taxa would exhibit competitive traits that limit access, while noncellulolytic taxa would display greater metabolic dependency, such as signatures of adaptive gene loss. We tested our hypotheses by evaluating genomic traits indicative of competitive exclusion or metabolic dependency, such as antibiotic production, growth rate, surface attachment, biomass degrading potential, and auxotrophy. The most 13C-enriched taxa were cellulolytic Cellvibrio (Gammaproteobacteria) and Chaetomium (Ascomycota), which exhibited a strategy of self-sufficiency (prototrophy), rapid growth, and competitive exclusion via antibiotic production. Auxotrophy was more prevalent in cellulolytic Actinobacteria than in cellulolytic Proteobacteria, demonstrating differences in dependency among cellulose degraders. Noncellulolytic taxa that accessed 13C from cellulose (Planctomycetales, Verrucomicrobia, and Vampirovibrionales) were also more dependent, as indicated by patterns of auxotrophy and 13C labeling (i.e., partial labeling or labeling at later stages). Major 13C-labeled cellulolytic microbes (e.g., Sorangium, Actinomycetales, Rhizobiales, and Caulobacteraceae) possessed adaptations for surface colonization (e.g., gliding motility, hyphae, attachment structures) signifying the importance of surface ecology in decomposing particulate organic matter. Our results demonstrated that access to cellulosic C was accompanied by ecological trade-offs characterized by differing degrees of metabolic dependency and competitive exclusion. IMPORTANCE Our study reveals the ecogenomic traits of microorganisms participating in the cellulose economy of soil. We identified three major categories of participants in this economy: (i) independent primary degraders, (ii) interdependent primary degraders, and (iii) secondary consumers (mutualists, opportunists, and parasites). Trade-offs between independent primary degraders, whose adaptations favor antagonism and competitive exclusion, and interdependent and secondary degraders, whose adaptations favor complex interspecies interactions, are expected to affect the fate of microbially processed carbon in soil. Our findings provide useful insights into the ecological relationships that govern one of the planet’s most abundant resources of organic carbon. Furthermore, we demonstrate a novel gradient-resolved approach for stable isotope probing, which provides a cultivation-independent, genome-centric perspective into soil microbial processes.
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Olowomofe, T. O., J. O. Oluyege, A. O. Ogunlade, and D. T. Makinde. "Microbial Assessment of Bed Linens in Ekiti State University Students’ Hostels." Journal of Advances in Microbiology, June 9, 2020, 43–52. http://dx.doi.org/10.9734/jamb/2020/v20i530244.
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Bed linen is clearly recognized as a potential reservoir for microorganisms and could be a vector of disease transmission. The present study was aimed at isolating and characterizing bacteria and fungi from different kinds of bed linen of student in Ekiti State University hostels. Pour plate method was used for the enumeration of total bacteria count from the posterior and anterior end of the bed linen. The average bacteria count for the anterior and posterior end was 7.46 and 7.16 Log10 CFU/ml respectively. The most dominant microbial species were bacteria and these were mostly found in the environment and on human skin. The bacteria isolated were Staphylococcus aureus, Staphylococcus epidermidis, Proteus mirabilis, Enterobacter aerogenes, Bacillus cereus, Escherichia coli and Klebsiella aerogenes. Bacillus cereus had the highest frequency of occurrence (25%), followed by Staphylococcus aureus (15%), Escherichia coli (15%), Klebsiella aerogenes (15%), Staphylococcus epidermis (15%), Enterobacter aerogenes (10%) and Proteus mirabilis (5%). The fungi isolates were Aspergillus sulphureus, Aspergillus fumigatus, Aspergillus niger, Aspergillus flavus and Fusarium spp. Antibiotics susceptibility test was carried out on the bacteria isolates with gram negative bacteria showing resistance to Cotrimoxazole and gram positive bacteria showing resistance to Amplicillin. Most of the bacteria isolates have multiple antibiotics resistance. The bacterial isolates were susceptible to Ciprofloxacin. Plasmid profiling was also done with Escherichia coli having three high molecular weight plasmids, Bacillus cereus and Enterobacter aerogenes do not possess plasmid. The identified species are suspected to be opportunistic pathogens for human, representing a risk for people with weakened immune system, especially in cases of super-infection.
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Sadeghi-Nejad, Batool, Eskandar Moghimipour, Sedigheh Yusef Naanaie, and Shahrzad Nezarat. "Antifungal and antibacterial activities of polyherbal toothpaste against oral pathogens, In vitro." Current Medical Mycology 4, no. 2 (2018). http://dx.doi.org/10.18502/cmm.4.2.65.
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 Original article
 Article History:
 Received: 23 April 2018 Revised: 20 July 2018 Accepted: 06 August 2018
 * Corresponding author:Batool Sadeghi-NejadAbadan School of Medical Sciences, Abadan, Iran.Email: batsad4@yahoo.com
 Introduction
 One of the most common chronic oral infections in the world is dental caries [1]. Oral pathogenic microorganisms have been the cause of dental plaques, dental caries, as well as gingival and periodontal diseases [2]. Streptococcus mutans is one of the main opportunistic pathogens of dental caries, which is responsible for the formation of dental plaque and caries [3]. Other microorganisms associated with this oral condition include Escherichia coli, S. aureus [4], and Candida species.
 C. albicans is the most frequent yeast isolated from the oral cavities with poor oral hygiene [2]. The formulation ingredients of commercial toothpastes are mostly chemical substances, such as fluoride and whitening agents [2]. The literature contains evidence regarding the adverse effects of fluoride and bleaching agents (e.g., peroxide-based agents) used in the commercial toothpastes [5].
 With this background in mind, the present study aimed to formulate a polyherbal toothpaste without any
 
 
 
 
 A B S T RA C TBackground and Purpose: Herbal toothpastes are more secure and efficacious and less
 poisonous due to containing natural chemicals as compared with the synthetic toothpastes. The present study aimed to formulate a polyherbal toothpaste using accessible medicinal plants in Iran and evaluate its efficiency in the protection of oral hygiene and prevention of dental caries.
 Materials and Methods: The developed toothpaste was made of the leaf extracts of Artemisia dracunculus, Satureja khuzestanica (Jamzad), and Myrtus communis (Linn), combined at four different dilutions, namely 1:4 (25%), 1:1 (50%), 3:4 (75%), and (100%), with sterile distilled water. The product was tested against five microorganisms, including Streptococcus mutans, Lactobaccilus caseie, S. sanguis, S. salivarius, and Candida albicans, using agar well diffusion method.
 Results: After 24 h of incubation, the maximum mean diameters of inhibition zone against L. caseie and C. albicans were obtained as 17-30 and 10-25 mm, respectively. Furthermore, the minimum mean diameter of inhibition zone against S. salivarious was estimated as 15-20 mm.
 Conclusion: The formulated toothpaste showed potent inhibitory activities against Gram-positive bacteria and C. albicans. Therefore, more studies are required to accurately investigate the efficacy of the formulated toothpaste.
 Keywords: Antibacterial, Antifungal, Oral pathogens, Polyherbal toothpaste, Yeast