ABSTRACT
Introducción. En el Archivo Nacional de la República de Cuba, existe contaminación electromagnética y la influencia del campo magnético oscilante de frecuencia extremadamente baja podría cuantificarse con microorganismos patógenos aislados de su ambiente interior. Objetivo. Cuantificar la influencia de este tipo de campo magnético sobre el crecimiento de microorganismos patógenos aislados del ambiente en el Archivo Nacional de la República de Cuba. Materiales y métodos. Se emplearon cinco microorganismos: Streptococcus sp. (1), Listeria sp. (2) y Candida guillermondii (3), aislados en el Archivo, así como Escherichia coli ATCC 25922 (4) y Saccharomyces cerevisiae (5), como referencia. Se les aplicó un campo magnético oscilante de frecuencia extremadamente baja de 60 Hz/220 V de 3 mT durante dos horas, en tres tubos de cultivo con agua destilada y con caldo nutriente. Después se inocularon 0,1 ml en placas de Petri con los medios de cultivo agar CromoCen SC (1 y 2), agar de dextrosa y papa (3), agar CromoCen CC 4227 (4) y agar con extracto de malta (5). Las colonias se contaron (log UFC/ml) mediante el procesamiento digital de las imágenes de las placas de Petri empleando el programa MatLab ® . Resultados. Se observó una estimulación significativa (p=0,05) de la cantidad de colonias tratadas con respecto a los controles, siendo mayor en el caldo nutriente que en el agua destilada y más en las bacterias (caldo nutriente-colonias tratadas: 9,43 a 10,62 UFC/ml) que en las levaduras (caldo nutriente-colonias tratadas: 8,31 a 8,79 UFC/ml). La estimulación se produjo en orden decreciente así: Listeria sp., E. coli ATCC 25922, Streptococcus sp., C. guillermondii y S. cerevisiae . Conclusión. Se concluyó que el campo magnético aplicado tuvo un efecto estimulante sobre los microorganismos estudiados, lo cual potencia el riesgo para la salud del personal y los visitantes del Archivo Nacional de la República de Cuba.
Introduction: Electromagnetic pollution has been detected at the Archivo Nacional de la República de Cuba and the influence of extremely low frequency magnetic fields could be quantified with pathogenic microorganisms isolated from the indoor environment. Objective: To quantify the influence of an extremely low frequency magnetic field on the growth of pathogenic microorganisms isolated from the environment at the Archivo Nacional. Materials and methods: We used five microorganisms isolated at the Archivo Nacional: Streptococcus sp. (1), Listeria sp. (2) and Candida guillermondii (3), and Escherichia coli ATCC 25922 (4) and Saccharomyces cerevisiae (5) as references. We applied this magnetic field of extremely low frequency, 60 Hz/220 V (3 mT), for two hours to these microorganisms on three culture tubes with distilled water and nutrient broth. Then we inoculated 0.1 mL in the following solid culture mediums on Petri dishes: CromoCen SC Agar (1 and 2), Potato Dextrose Agar (3), CromoCen DC 4227 (4) and Malt Extract Agar (5). The colonies were counted (log CFU/mL) by digital processing of the images of Petri dishes using the MatLab ® tool. Results: We observed a statistically significant stimulation (p=0.05) in the quantity of treated colonies as compared to controls, which was higher in nutrient broth than in distilled water, and in bacteria (nutrient broth and treated colonies: 9.43 to 10.62 CFU/mL) as compared with yeasts (nutrient broth-treated colonies: 8.31 to 8.79 CFU/mL). In decreasing order, stimulation was as follows: Listeria sp., E. coli ATCC 25922, Streptococcus sp., C. guillermondii and S. cerevisiae . Conclusion: We concluded that the magnetic field applied had a stimulating effect on the microorganisms under study, which increases the risk to the health of staff and visitors at the Archivo Nacional .
Subject(s)
Humans , Archives , Bacteria/growth & development , Yeasts/growth & development , Environmental Microbiology , Electrical Equipment and Supplies/adverse effects , Magnetic Fields , Bacteria/radiation effects , Yeasts/radiation effects , Image Processing, Computer-Assisted , Disease Reservoirs , Occupational Health , Cuba , Bacterial Load , Mycology/methodsABSTRACT
The occurrence of psychrotrophic bacteria in raw milk is studied worldwide due to the difficulties associated with controlling their growth during cold storage and the consequent negative effects upon fluid milk or dairy products. Among the psychrotrophic bacteria, the genus Pseudomonas (represented primarily by P. fluorescens) has been highlighted as the cause of numerous defects in dairy products. In light of its perceived predominance, this species has frequently been chosen as a model organism to assess the effects of psychrotrophic bacteria on milk or to evaluate the efficacy of control measures. However, recent findings derived from the application of molecular biological techniques have exposed a number of deficiencies in our knowledge of the biology of milk-associated psychrotrophs. Furthermore, it has been revealed that microbe to microbe communication plays a significant role in determining both the identities and the extent to which different groups of microbes develop during cold storage. The application of molecular identification methods has exposed errors in the classification of members of the genus Pseudomonas isolated from cold stored milk and has stimulated a reevaluation of the presumed status of P. fluorescens as the predominant milk-associated psychrotrophic species. This article presents a succinct review of data from studies on psychrotrophic bacteria in milk, some of which contest established theories in relation to the microbiology of cold stored raw milk, and poses the question: how much do we really know?.
Subject(s)
Animals , Biodiversity , Bacteria/classification , Bacteria/radiation effects , Milk/microbiology , Cold TemperatureABSTRACT
To evaluate the impact of diagnostic mastoid X-ray in the improvement of the outcome of active safe chronic suppurative otitis media [CSOM]. Retrospective study, for two groups of patients. A total of 270 patients with safe active CSOM were managed by routine aural toilet, antibiotics and decongestant, divided in to two groups, those who were not exposed to diagnostic x-ray [Group I] and those who were exposed to diagnostic mastoid x-ray [group II]. Oto-Rhino-Laryngological Department in Mosul General Hospital and Al-Rahma hospital during the period from January 2002 to December 2004. The final result after 10-15 weeks of follow-up indicated that 50% of patients had complete dryness of the ear from discharge in those exposed to diagnostic X-ray and Only 25% of those not exposed to diagnostic X-rays showed complete dryness of the ear, [p-value = 0.000] which is statistically a significant result. Some patients with active safe CSOM may get benefit from exposure to diagnostic mastoid X-rays
Subject(s)
Humans , Male , Female , Otitis Media, Suppurative/therapy , Chronic Disease , Radiography , X-Rays , Treatment Outcome , Mastoid/diagnostic imaging , Retrospective Studies , Bacteria/radiation effectsABSTRACT
The present study was aimed to design a simple model to check efficacy of germicidal UV tube, to standardise the position, distance and time for UV light and also to find out its efficacy against medically important bacteria, the bacterial spores and fungi. The microbial cultures tested included gram positive and gram negative bacteria, bacterial spores and fungal spores. The microbes streaked on solid media were exposed to UV light. The inactivation of the order of four logs was observed for bacteria. UV light can have efficient inactivation of bacteria up to a distance of eight feet on either side and exposure time of 30 minutes is adequate.
Subject(s)
Bacteria/radiation effects , Colony Count, Microbial , Disinfection/methods , Fungi/radiation effects , Microbial Viability , Spores, Bacterial/radiation effects , Spores, Fungal/radiation effects , Time Factors , Ultraviolet RaysABSTRACT
O laser de baixa potência vem sendo usado para acelerar a cicatrização em úlceras de pressão devido a seus efeitos cicatrizantes, antiinflamatório, antiedematoso e analgésico. No entanto, não há consenso quanto a seu efeito em úlceras infectadas. O objetivo deste estudo foi verificar o efeito bactericida da laserterapia e da terapia fotodinâmica...
Low-level therapy has been used to speed up healing process of pressure ulcers due to its antiinflammatory, analgesic, anti-edematous, and scarring effects. However there is no consensus on its effect on infected ulcers. The aim of this study was to verify the bactericidal effect of low-level laser therapy...
Subject(s)
Bacteria/radiation effects , Photochemotherapy , Low-Level Light TherapyABSTRACT
To evaluate the effect of diagnostic x-ray in vitro study on bacteria causing chronic suppurative otitis media. The Number of viable cell count pre and post exposure to different doses of radiation was estimated. Ear, nose and throat Dept. in Erbil Military hospital, Microbiology and x-ray unit in general hospital- Mosul Iraq during the period from July 1999 to July 2000. The effect of ionizing radiation [x-ray] has been studied on different strains of bacteria in vitro. The final results showed that there is a statistically significant reduction in the number of viable cell count of certain microorganisms after exposure to a specific dose of radiation in vitro. The single small dose of x-ray radiation [diagnostic x-ray dose] reduced the number of viable cells of certain microorganism in vitro
Subject(s)
Radiation Effects , Bacteria/radiation effects , Chronic DiseaseABSTRACT
Urinary tract infection in cancer patients is of major importance not only because it is of common occurrence but also because it may be the source of blood invasion by bacteria or their products. In this study, 130 midstream urine samples collected from patients with cancer bladder were cultured on different media. All isolated bacteria and yeast were identified systematically and than subjected to these investigations: Sensitivity to increasing doses of gamma radiation, sensitivity to different antimicrobial agents and measurement of DNA content by cytophotometry. Bacteria and yeast were isolated from urine in 73 cases [56.15%] of all cases [130]. E. coli was isolated in 31.4%, Pseudomonas aeroginosa in 21.9%, Proteus in 12.3%, Staph. aureus in 18.2% and Candida in 4.1%. Pseudomonas was the most sensitive organism to gamma radiation D10 [0.06 KGy] followed by E. coli D10 [0.35 KGy] then Staph. D10 [0.36 KGy] while Candida was the most radio resistant D10 [1.11 KGy]. All tested organisms had higher DNA content after exposure to therapeutic dose of radiation than before radiation. These changes in DNA content lead to changes in the sensitivity of organism to different antibiotics, sublethal doses of radiation cause an increase in spontaneous emergency of resistant mutants. Changes in DNA content and antibiotic sensitivity were statistically significant