Peracetic Acid: A Practical Alternative to Formalin for Disinfection of Extracted Human Teeth

Extracted human teeth provide the closest approximation to teeth in situ and play important roles in dental education and materials research. Since extracted teeth are potentially infectious, the Centers for Disease Control recommend their sterilization by autoclaving or disinfection by formalin immersion to ensure safe handling. However, autoclaving is not recommended for teeth with amalgam fillings and formalin is hazardous. The goal of the present study was to investigate the potential of peracetic acid (PA) as an alternative method to achieve reliable disinfection of freshly extracted teeth. A total of 80 extracted teeth were collected for this study. Whole teeth were incubated in one of four solutions for defined periods of time: sterile water (2 weeks), formalin (2 weeks), PA 1000 ppm (2 weeks), and PA 2000 ppm (1 week). After sectioning, the crown and root fragments were transferred into separate tubes containing brain–heart infusion broth and incubated at 37 °C under anaerobic conditions for 72 h. Absence of broth turbidity was used to assess effectiveness of disinfection. No turbidity was observed in any of the formalin-treated or peracetic acid-treated samples, signifying complete disinfection. Our results indicate that PA can effectively disinfect extracted human teeth, providing a reliable alternative to formalin and autoclaving.

The ability of Aliarcobacter butzleri strains isolated from foods of animal origin in Costa Rica to form biofilm

Aliarcobacter butzleri is a zoonotic emerging food and waterborne pathogen widely distributed in nature. It is present in food processing environments and can easily be spread through the food industry because of its ability to form biofilm. The aim of this work was to determine the ability of strains isolated in Costa Rica from different food matrixes of animal origin to form biofilm. Thirty-eight A. butzleri strains previously isolated and identified from animal origin products were analyzed using the method described by Stepmovic et al. (2000), in three culture broths, brain heart infusion broth, Boer broth and Houf broth. Results showed that 67% of poultry origin strains, 62.5% of meat origin strains and just 8% of milk origin strains showed ability to form biofilm. The findings of this study confirm the adherence ability of A. butzleri to form biofilm, a characteristic that can promote dispersion and cross contamination along food industry processing lines.

Imprint and spreading techniques for the isolation and identification of subungueal fungi in claws of healthy cats

The aim of this study was to compare imprint and spreading techniques for the isolation and identification of colonies of pathogenic and non-pathogenic fungus in the claws of semidomiciliated cats. For that propose, 150 cats were evaluated, subdivided into three groups of 50 animals. In the first and second groups, the cats were submitted to the imprint technique in Petri dishes containing Selective Mycobiotic Agar: In the first group, the cats were subjected underwent antisepsis with 70% ethanol of the claws of the thoracic limbs and in the second group the animals were subjected underwent antisepsis with 70% ethanol of the claws of only one of the thoracic limbs. The third group was submitted to the spreading technique, whose material was collected by rubbing a sterile swab moistened with brain-heart infusion broth, in the claws of the forelimbs, where an aliquot of the material was transferred to Petri dishes containing Selective Mycobiotic Agar. The material was stored at 25°C for 30 days. The readings were performed on days 5, 7, 15, and 30 post incubation. Using the imprinttechnique performed under the conditions of this experiment, we were not able to isolate and identify the colonies because since day 5, they were overlapped. From the spreading technique, Mucor sp. (54,34%), Rhodotorula sp. (28,26%), Fusarium sp. (21,73%), Aspergillus sp. (21,73%), Trichoderma sp. (19,56%), Penicillium sp. (19,56%), Cladosporium sp. (10,86%), Rhizopus sp. (8,68%), Acremonium sp. (6,5%), Exophialia sp. (6,5%), Paecilomyces sp. (4,34%), Trichosporon sp. (4,34%), and Geotrichum sp. (2,17%) were isolated. It was concluded that the spreading technique proved to be useful in isolating fungal colonies from feline claws, and the animals do not present symptoms, which signals the importance of them as possible sources of exposure for tutors. The cats were negative for Sporothrix sp. by the imprint and spreading techniques.

THE EFFECTS OF FEEDING DIETS CONTAINING FURAZOLIDONE* ON EXPERIMENTAL SALMONELLA GALLINARUM INFECTION IN CHICKENS

Twenty eight week-old chickens infected orally with 16.5x109 viable Salmonella gallinarum organisms in 3ml. brain heart infusion broth were shown to be protected against infection by -feeding them on diets containing either 0.0055 percent or 0.011 percent furazolidone. The higher concentration was more effective as judged by the clinical symptoms, mortality, egg production, post mortem lesions and the isolation of the infecting organism from the visceral organs of the dead chickens. About 600 isolates of E. coli from the.chickens both before and during the course of infection·were sensitive to furazolidone disc (100mcg). The infecting organism and about 300 isolates of the organism tested during the course of infection were also sensitive furazolidone. No ''carriers" were detected in :chickens fed on diet containing 0.011 percent furazolidone.It is therefore recommended that furazolidone can be used effectively as feed additive for poultry.

Antimicrobial packaging and high hydrostatic pressure: Combined effect in improving the safety of coalho cheese

Active cellulose acetate films incorporated with oregano essential oil (antimicrobial film) were previously subjected to high hydrostatic pressure treatment (300 MPa/5 min (FHP1) or 400 MPa/10 min (FHP2)) and investigated for possible changes in their antimicrobial efficiency. In parallel, the efficiency of the antimicrobial films, high hydrostatic pressure (300 MPa/5 min or 400 MPa/10 min), or a combination of antimicrobial film and high hydrostatic pressure, was tested on coalho cheese, experimentally contaminated with Listeria monocytogenes, Escherichia coli, and Staphylococcus aureus, stored for 21 days under refrigeration. Investigations in culture media (agar, brain–heart infusion broth, and micro-atmosphere) detected antimicrobial efficiency for all films, with or without high hydrostatic pressure, against the three bacteria. However, the data indicated that the treatment with 300 MPa/5 min may have impaired the migration of oregano essential oil from FHP1, justifying its lower efficiency in solid medium and brain–heart infusion broth. In cheese samples, the combination of antimicrobial film and 400 MPa/10 min caused greater reductions in counts for the three microorganisms, at zero time throughout the entire coalho cheese storage. Only antimicrobial film or combination (antimicrobial film and high hydrostatic pressure) were able to control microbial multiplication during the 21 days. Therefore, the results confirm that the individual use of high hydrostatic pressure (300 MPa/5 min or 400 MPa/10 min) at the level evaluated can allow bacterial multiplication during storage and that the combination of antimicrobial packaging and high hydrostatic pressure has greater potential to ensure a safer coalho cheese.

Pilot Study of the SCFA Headspace Analysis of Streptococcus mutans Metabolites in Media with and without Polyols

This pilot study of Streptococcus mutans ATCC 35668 grown in media with and without polyols (erythritol) measured the resultant metabolites, including the short chain fatty acids by using head space analysis. Brain Heart Infusion Broth (BHI2 or BHI10) supplemented with 2% or 10% sucrose containing no polyols or either erythritol or xylitol and Streptococcus mutans (ATCC 35668) was grown aerobically. After 48 hours of growth the supernatant were harvested and centrifuged to pellet bacteria. Supernatants were removed from bacterial pellets then submitted for Short Chain Fatty Acid (SCFA) analysis with an Agilent Technologies (Santa Clara, CA 95051) system configured from three components, a 5973 mass selective detector, a 6890N gas chromatographer, and a 7697A headspace sampler. Streptococcus mutans growing in Brain Heart Infusion Broth (BHI2 or BHI10) supplemented with 2% or 10% sucrose but containing no polyols produced the following short chain fatty acids: methyl isovalerate, acetic acid, propionic acid, butanoic acid, pentanoic acid, ethyl butaric acid, 4-methylvaleric acid, hexanoic acid. When the Brain Heart Infusion Broth (BHI2 or BHI10) supplemented with 2% or 10% sucrose containing erythritol was used as media for this Streptococcus mutans strain, the following were produced: ethanol, acetoin, and acetic acid. Our results would suggest that constituents of the media may affect the bacterial metabolite production.

Optimization Growth Conditions of Vibrio cholerae Ogawa in Medium BHIB to Extend Shelf Life of Working

Balai Besar Pengawas Obat dan Makanan (BBPOM) berkewajiban untuk menguji setiap produk pangan dari cemaran bakteri patogen sebelum diedarkan untuk mencegah terjadinya wabah penyakit yang ditularkan lewat makanan termasuk salah satunya Vibrio cholerae.Dalam proses pengujian produk pangan terhadap cemaran V. cholerae, terdapat masalah dalam hal ketahanan hidup kultur kerja V. cholerae.Penelitian ini merupakan penelitian eksperimental laboratorik dengan menggunakan Rancangan Acak Lengkap(RAL) Pola Faktorial.Tujuan dari penelitian ini untuk mendapatkan waktu pertumbuhan maksimal kultur V. cholerae Ogawa pada media (Brain Heart Infusion Broth)BHIB pada suhu 37oC serta untuk mendapatkan kombinasi derajat keasaman (pH) dan konsentrasiNaCl yang tepat pada medium BHIB untuk meningkatkan umur kultur kerja V. cholerae Ogawa yang disimpan pada suhu kulkas (4-8oC). Penelitian diawali dengan re-identifikasi isolat kemudian dilakukan uji kurva tumbuh dengan inkubasi 37oC selama 15 jam pada medium BHIB. Setelah diperoleh pola pertumbuhannya pada medium BHIB, penelitian dilanjutkan dengan menguji ketahanan V. cholerae Ogawa pada medium BHIB yang dimodifikasi dengan kombinasi pH (5,6,7,8, dan 9) dan konsentrasi NaCl (0,1,2, dan 3%) pada penyimpanan suhu kulkas (4-8oC). Hasil penelitian uji kurva tumbuh pada medium BHIB menunjukkan bahwa fase log (pertumbuhan maksimal) terjadi pada jam ke-5. Hasil uji ketahanan pada medium BHIB yang dimodifikasi dengan kombinasi pH dan konsentrasi NaCl menunjukkan bahwa kombinasi pH 9 dan NaCl 3% merupakan kombinasi terbaik untuk meningkatkan umur daya simpan V. cholerae Ogawa pada medium BHIB. Pada kombinasi tersebut V. cholerae Ogawa mampu bertahan sampai hari ke-51 pada penyimpanan suhu kulkas (4-8oC).