Brain Heart Infusion Research Articles

P383 ‘It's not Fungus, its Nocardia’—an elementary diagnostic challenge for draining sinus on abdominal wall (rare): a case report

Poster session 3, September 23, 2022, 12:30 PM - 1:30 PMIntroductionA rare finding of abdominal wall clinical presentation of persistent progressive tumefaction with draining sinus with no granules caused by Nocardia brasiliensis.MethodsHistory: A 22-year-old presented to the Dermatology OPD with complaints of swelling and tenderness and discharging sinuses with no granules around the periumbilical region in the lower abdominal area for three years. His initial fine needle aspiration cytology specimen report was inconclusive. He received anti-Kochs treatment based on a positive Montoux test and family history from outside the hospital.Initially punch biopsy samples were sent for fungal processing to our laboratory which was inconclusive. Repeat pus aspirate and punch biopsy samples were subjected to conventional techniques. The sample was inoculated on Sabouraud's Dextrose agar, Brain heart Infusion agar, and Lowenstein-Jensen media. Direct Smear was subjected to Gram stain and Modified Zeihl Neelson stain with 1% Sulfuric acid as decoloriser.ResultsOn Gram stain, Gram-positive filamentous bacilli against a background of pus cells in pus aspirate only (not in punch biopsy specimens).Modified Zeihl Neelson stain with 1% Sulfuric acid decoloriser was performed on all three samples. Beaded acid-fast filamentous bacilli with plenty of pus cells in the background were seen in pus aspirate only (not in punch biopsy specimens).No fungal elements were observed on the 20% KOH mount.Clinicians were notified immediately with the provisional report of possible Actinomycetoma due to Nocardia sp.Growth was observed within 9 days on SDA as well as LJ. It was a chalky white, dry colony to begin with that turned orangish-yellow in another week's time. Smear from the colony showed Gram-positive filamentous bacilli which on Modified ZN Smear were acid-fast filamentous beaded bacilli. The isolate was identified as Nocardia species. This was further confirmed as Nocardia brasiliensis by MALDI-TOF.On admission, the patient was initially started on Inj. Amikacin and then changed to Modified Raman regime of double dose Cotrimoxazole and Gentamicin. His lesions started showing improvement over 2 weeks of in-patient treatment. He was discharged on oral treatment thereafter.ConclusionAbdominal wall clinical presentation of persistent progressive tumefaction with draining sinus with no granules caused by N. brasiliensis is a rare clinical entity as Mycetoma. The differential diagnosis would lead to either bacterial or fungal etiology or neoplasia.Delay in correct diagnosis led to the chronicity of the clinical presentation with inappropriate therapy.For a chronic destructive debilitating infective mycetoma presentation, appropriate microbiological diagnostics become essential to have early correct detection with proper sampling technique to guide the appropriate therapy as per the causative pathogen.

P225 Subcutaneous phaeohyphomycosis by Phaeoacremonium species in a renal transplant recipient

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PMObjectivePhaeohyphomycosis refers to infections due to a large group of heterogenous organisms called ‘dematiaceous’ or ‘melanized’ fungi. The infection exhibits a wide spectrum of presentations such as deep local infections, pulmonary infection, cerebral infection, and disseminated disease, which are associated with high mortality. The incidence of phaeohyphomycosis among solid organ transplant recipients is 0.7%. Hereby, we report a case of phaeohyphomycosis in a post renal transplant patient who presented with a subcutaneous swelling over the right elbow region.MethodA detailed history was obtained from the patient after informed consent. The cystic fluid was subjected to microbiological including bacterial (Gram stain, culture on blood agar incubated at 37°C) and fungal investigations [Calcofluor potassium hydroxide (KOH) mount, culture on Sabouraud dextrose agar (SDA) incubated at 37°C and 25°C and brain heart infusion agar (BHI) incubated at 25°C]. The identification of isolate was done phenotypically by preparing lactophenol cotton blue (LCB) mount from slide culture and molecular technique using Sanger's sequencing.ResultA 61-year-old diabetic and post renal transplant (7 years) male presented with complaints of swelling over the right elbow region for 5 months duration. Swelling was insidious in onset, gradually progressive, painless, cystic, non-pulsatile, non-reducible, ∼9 × 7 cm in size, lobular in shape with irregular surface having normal overlying skin which minimally restricting the movement of the elbow. There was no history of trauma over the elbow region. Reddish purulent pus was received for mycological investigation. Calcofluor KOH mount demonstrated septate hyphae. Culture on SDA incubated at 37°C and 25°C grew cream-colored colonies, turning grayish beige to olive-brown and developed clusters of aerial hyphae with reverse tan to brown in color after 2 weeks of incubation. LCB mount showed hyaline to brownish hyphae, cylindrical phialides growing along the hyphae with slightly tapering towards the apex, hyaline, oblong, conidia, gathering in clusters at end of phialide. Phenotypically, the fungus was identified as Phaeoacremonium species and molecular identification and antifungal susceptibility are awaited. Patient was advised for surgical excision but he left against medical advice. Currently, he is not receiving any antifungals.ConclusionPhaeohyphomycosis is a rare and unique entity among fungal infections. Cutaneous phaeohyphomycosis predominantly occurs on the extremities with a localized solitary nodule or abscess. A high index of suspicion and the surgical approach including excision or debridement are mainly chosen.

P205 Uncommon Aspergillus species encountered in human infections

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM Objective Aspergillus species are ubiquitously found in environment and have propensity to infect both immunocompromised as well as immunocompetent individuals. Though the most common species implicated in human illness include Aspergillus fumigatus and A. flavus, many uncommon Aspergillus species are increasingly being reported. Moreover, these Aspergillus species have the potential to afflict varied organ systems and can thereby, be implicated in a wide array of infections. Here, we describe three patients infected by rare Aspergillus species viz. A. sclerotium, A. cristatus, and A. japonicum causing brain abscess, corneal ulcer and chronic dacrocystitis.MethodsUncommon Aspergillus species were isolated from clinical samples (nasal scraping, corneal scraping, and brain biopsy). Samples were inoculated on Sabouraud dextrose agar (incubated at 37°C and 25°C) and brain heart infusion agar (incubated at 25°C), followed by slide culture and lactophenol cotton blue (LCB) mount. The isolates were further subjected to molecular identification using polymerase chain reaction (PCR) targeting ITS region, followed by sequencing. Demographic details, clinical characteristics, risk factor, and management profile associated with these Aspergillus species were evaluated. We conducted systematic review using the search terms ‘A. sclerotium’ AND ‘humans’, ‘A. cristatus’ AND ‘humans’ and ‘A. japonicum’ AND ‘humans’.ResultsWe isolated three newer Aspergillus species from nasal scraping, corneal ulcer and brain biopsy. Direct microscopy using potassium hydroxide-calcofluor mount from all these clinical samples showed hyaline septate hyphae in background of pus cells. After 3-5 days of incubation, yellow-green mycelia were observed on the obverse in all the isolates. However, their microscopic features did not relate with the typical lactophenol cotton blue (LCB) picture of A. flavus, owing to which these were sub-cultured on Czapek Dox agar. After 4-5 days of incubation, LCB of these isolated again failed to divulge any specific picture and these isolates were subjected to molecular identification.Nasal scraping from 31-year-old immunocompetent male who presented with post-traumatic chronic dacrocystitis and recurrent orbital cellulitis yielded A. japonicum. He responded well with empirical antibiotics and oral voriconazole.Corneal scrapings from 56-year-old immunocompetent male who presented with post-traumatic blurring of vision yielded A. cristatus. He was treated with nystatin and voriconazole with good response.Brain biopsy from 45-year-old male with hypertension and subarachnoid hemorrhage, who presented with fever, headache, vomiting and periorbital swelling yielded A. sclerotium. He was treated with amphotericin B and had favorable outcome.The systematic literature review didn't yield any results of infection caused by these species in humans.ConclusionThis is the first report of isolation of A. sclerotium, A. japonicum, and A. cristatus from human tissue, though these fungi have been isolated from ambient air and environment. The present report highlights the emergence of uncommon Aspergillus species causing invasive infections even in immunocompetent patients and the requisite of molecular modalities to aid in identification of these rare, emerging species.

THE BIOLOGICAL FUNCTIONS OF IMMUNOGLOBULIN Y (IgY) MOLECULES IN AGAINST INFECTION OF Enterococcus faecalis ORIGIN OF RED TILAPIA

Red tilapia (Oreochromis hybrid) is Indonesia's leading freshwater fishery commodity susceptible to streptococcal bacterial infection. Many studies have been conducted on various efforts to prevent and treat this disease, one of which uses the immunoglobulin Y (IgY) molecule from chicken egg yolk. This study aimed to observe the biological function of IgY against Enterococcus faecalis as a cause of streptococcal-like infection. The agglutinin function was conducted by observing the growth of Enterococcus faecalis in brain heart infusion (BHI) broth media which was added with IgY suspension. The function of inhibin was performed using a spectrophotometric method to measure the level of turbidity of the bacterial suspension inoculated with IgY suspension. The bactericidal potential through the complementary activation pathway for red tilapia serum was carried out using a scanning electron microscope (SEM) method to evaluate the topography of the bacterial cell wall. The results of the study can be concluded that IgY anti-Enterococcus faecalis has the potential as an agglutinin, inhibin, and bactericidal agent through its putative potential in complement activation in streptococcal bacterial infections in red tilapia commodities.

Mucosal Environment Induces Phage Susceptibility in Streptococcus mutans.

Pathogenic bacteria are attracted toward mucosa, as it is their way of entry into the body. However, we know surprisingly little about the phage-bacterium interactions in the mucosal environment. Here, we explored the effect of the mucosal environment on growth characteristics and phage-bacterium interactions in Streptococcus mutans, a causative agent of dental caries. We found that although mucin supplementation increased bacterial growth and survival, it decreased S. mutans biofilm formation. More importantly, the presence of mucin had a significant effect on S. mutans phage susceptibility. In two experiments done in Brain Heart Infusion Broth, phage M102 replication was detected only with 0.2% mucin supplementation. In 0.1 × Tryptic Soy Broth, 0.5% mucin supplementation led to a 4-log increase in phage titers compared with the control. These results suggest that the mucosal environment can have a major role in the growth, phage sensitivity, and phage resistance of S. mutans, and underline the importance of understanding the effect of mucosal environment on phage-bacterium interactions.

A protocol for the cultivation and monitoring of ileal gut microbiota surrogates.

This research aimed to develop and validate a cultivation and monitoring protocol that is suitable for a surrogate microbial community that accounts for the gut microbiota of the ileum of the small intestine. Five bacterial species have been selected as representatives of the ileal gut microbiota and a general anaerobic medium (MS-BHI, as minimally supplemented brain heart infusion) has been constructed and validated against BCCM/LGM recommended and commercial media. Moreover, appropriate selective/differential media have been investigated for monitoring each ileal gut microbiota surrogate. Results showed that MS-BHI was highly efficient in displaying individual and collective behaviour of the ileal gut microbiota species, when compared with other types of media. Likewise, the selective/differential media managed to identify and describe the behaviour of their targeted species. MS-BHI renders a highly efficient, inexpensive and easy-to-prepare cultivation and enumeration alternative for the surrogate ileal microbiota species. Additionally, the selective/differential media can identify and quantify the bacteria of the surrogate ileal microbial community. The selected gut microbiota species can represent an in vitro ileal community, forming the basis for future studies on small intestinal microbiota. MS-BHI and the proposed monitoring protocol can be used as a standard for gut microbiota studies that utilize conventional microbiological techniques.

Assessment of biofilms formation of bacterial and fungal isolates using qualitative Congo red agar and semiquantitative crystal violet microtiter methods

Introduction. Sixty-five percent of human infections are caused by bacteria or yeasts able to form biofilms. This feature makes them more resistant to antimicrobials and antifungals. Objective. To determine biofilm formation capacity of bacterial and fungal isolates by quantitative crystal violet microtiter and qualitative Congo red agar methods. Materials and methods. Brain-heart infusion, trypticase soy broth and Müeller‑Hinton culture media were used in bacterial isolates for the quantitative method; brain-heart infusion broth and Sabouraud dextrose were used for yeasts. The same culture media plus 3% Congo red and 10% dextrose were used to apply the qualitative method in agar. The proposal by Stepanovic, et al. was used as a reference method. Results. We evaluated 103 bacterial isolates and 108 yeasts isolates. We did not recommend substitute brain-heart infusion broth for trypticase soy and Müeller-Hinton broths for biofilm formation assessment in bacterial isolates using the quantitative method. Sabouraud dextrose medium, both broth and agar, can replace brain-heart infusion to assess biofilm formation in yeasts, quantitatively and qualitatively. Conclusion. The study of biofilms in the microbiology laboratory, using Congo red agar qualitative method, is a simple, fast, and inexpensive procedure that provides precise information for the diagnosis and treatment of persistent infections caused by bacteria and yeasts.

Effect of Nutmeg (Myristica Fragrans) Methanolic Extract to the Growth of Dental Plaque Bacteria

Background: One of the causes of dental caries is Streptococcus mutant bacteria which has the ability to change the sugar content of food waste into lactic acid as the initial process of caries. One of the efforts to overcome dental caries is to use natural ingredients such as nutmeg. Every part of nutmeg has active substances that are efficacious as antimicrobial, antibacterial, antioxidant, antifungal and anti-inflammatory. Pulpam, seeds and fuli of nutmeg showed as potential extracts in inhibiting the growth of Streptococcus mutans. Objective: This study aimed to analyze methanol extracts from pericarpium, pulpam, fuli and nutmeg seeds against the growth of Streptococcus mutans bacteria that causes dental plaque. Methods: The research was conducted by diffusion method using BHI agar media and incubated anaerobically at 37°C for 24 hours. Results: The results of the calculation of the average diameter of the inhibition zones from the extract of fuli, seeds, pulpam and pericarpium of the nutmeg plant were 19.00 mm, 25.33 mm, 15.66 mm, 22.66 mm, and 21.83 mm, respectively. Data analysis using ANOVA (one way) showed that there were significant differences in all groups at p<0.05. The results of the LSD test showed that there were significant differences in all treatment groups. Conclusion: Methanol extract from fruit and fruit parts of nutmeg showed the ability to inhibit the growth of bacteria that cause dental plaque.

Effect of Sodium Hypochlorite in Dental Unit Waterline on Aerosolized Bacteria Generated from Endodontic Procedures

IntroductionAerosol generation in a dental setting is a critical concern, and approaches that aim at decreasing bacterial load in aerosols are of high priority for dental professionals. The objectives of this study were to evaluate the relative effect of various endodontic procedures on the generation and dissemination of aerosols and the effect of 0.1% sodium hypochlorite (NaOCl) in dental unit waterlines (DUWLs) on the bacterial load in the generated aerosols in a clinical setting. MethodsThe study was completed in 2 phases. The classic passive sampling technique using brain-heart infusion agar plates was used. Agar plates were strategically placed throughout the operatory at predefined locations. In phase 1, to evaluate the effect of different endodontic procedures on the generation and dissemination of aerosols, we collected a total of 38 samples. After baseline collection, test samples were collected during vital pulp therapy (VPT) full pulpotomy (n = 10), nonsurgical root canal therapy (NSRCT, n = 10), surgical root canal therapy (SRCT, n = 10), and incision and drainage (n = 8) procedures. Bacterial growth was expressed as colony-forming units at 48 hours after sample collection. Data were analyzed using 1-way analysis of variance with the Tukey multiple comparison post hoc test. In phase 2, to evaluate the effect of 0.1% NaOCl in the DUWL on the bacterial load in the generated aerosols, a total of 30 samples were collected. All procedures including VPT (n = 10), NSRCT (n = 10), and SRCT (n = 10) were performed with 0.1% NaOCl in the DUWL. Bacterial growth was expressed as colony-forming units at 48 hours after sample collection. Data were analyzed using 2-way analysis of variance with the Tukey multiple comparison post hoc test. ResultsAll endodontic procedures generated aerosols at all tested locations, except incision and drainage. Aerosols were disseminated as far as 3 m from the patient's head with no significant difference between various locations (P > .05). VPT procedures generated the maximum number of aerosols compared with NSRCT and SRCT. Adding 0.1% NaOCl to DUWLs significantly reduced the bacterial load in the generated aerosols in all treatment groups compared with groups treated with untreated waterlines (P < .05). No significant difference was noted in the bacterial load between all groups with treated waterlines (P > .05). ConclusionsAll tested endodontic procedures led to the generation and dissemination of contaminated aerosols, and the addition of 0.1% NaOCl as a biocide to the DUWL led to a statistically significant reduction in the bacterial load.

Detection and molecular characterization of VRE isolates in Slovakia from stool samples positive for Clostridioides difficile toxins.

The study aimed to identify colonized patients as a possible source of eventual VRE (vancomycin-resistant enterococci) infection from stool samples positive for glutamate dehydrogenase antigen, as well as for Clostridioides difficile toxins A and B. The study was carried out from 7/2020 to 9/2021. Stool samples were grown in a brain heart infusion medium with a gram-positive non-spore-forming bacteria supplement under aerobic conditions. The samples for VRE identification were grown on CHROMID® VRE agar, and the MICs for vancomycin and teicoplanin were also estimated. The presence of the vanA/vanB genes was tested using the PCR method. The total number of 113 stool samples positive for Clostridioides difficile toxins was analyzed. Of these samples, 44 isolates with VRE characters were identified. The most prevalent isolates in our set of isolates were Enterococcus faecium (27 isolates, 62%), Enterococcus faecalis (9 isolates, 21%), Enterococcus solitarius (4 isolates, 9%), Enterococcus durans (2 isolates, 4%), 1 isolate Enterococcus sulfurous (2%), and Enterococcus raffinosus (2%). In total, 26 isolates were detected in the study in the presence of vanA genes (24 isolates E. faecium, 2 isolates E. faecalis) and 18 isolates detected in the presence of vanB genes (7 isolates E. faecalis, 4 isolates E. solitarius, 3 isolates E. faecium, 2 isolates E. durans, 1 isolate E. sulfurous, and E. raffinosus). The results of this study showed the local dominance character of the vanA gene of hospital VRE isolates that were carriers of genes associated with high resistance to vancomycin, teicoplanin, and occasionally linezolid.

In vitro Evaluation of Antimicrobial Activity of Brazilian Red Propolis Containing-dentifrice

Published on:August 2022Journal of Young Pharmacists, 2022; 14(3):333-336Original Article | doi:10.5530/jyp.2022.14.65Authors: Francineudo Oliveira Chagas1, João Hildo de Carvalho Furtado Júnior1, Hilana Valéria Dodou1, Marta Maria de França Fonteles1, Renato Daniel de Freitas2, Edilson Martins Rodrigues Neto1, Emmanuel Arraes de Alencar Júnior1, Juliana Araujo Sarmento3, Sarah Gabrielle Sousa de Oliveira Rodrigues4, Patricia Leal Dantas Lobo1, Ana Cristina de Mello Fiallos1, Mary Anne Medeiros Bandeira1 1Pharmacy, Dentistry and Nursing School, Federal University of Ceará, Fortaleza, BRAZIL.2Dental School, Federal University of Ceará, Sobral, BRAZIL. 3Dental School, Sao Leopoldo Mandic, Campinas, BRAZIL.4Medical School, Assis Chateaubriand Maternity School- MEAC, Fortaleza, Ceará, BRAZIL. Abstract: Background: This study evaluated the antimicrobial activity of brazilian red propolis (BRP) dentifrice and compare in vitro. Materials and methods: Strains of S. mutans ATCC UA159 were used in the present study. This study compared the antibacterial effects of BRP extract, BRP containingdentifrice and one antimicrobial commercial dentifrice (Parodontax) against S. mutans. For the evaluation of the antimicrobial activity the microdilution method was used in culture broth. The strain was activated by incubation at 37°C overnight in Brain Heart Infusion (BHI) culture medium, in an anaerobic jar. To the wells of the microplates were added 100μL of BHI broth, 20μL of the substances tested (experimental groups), at concentrations ranging from 100 μL/mL to 0.0488 μL/mL, and 80 μL/mL of the standardized microbial suspension. The microplates were incubated for 24 hr in a bacteriological oven at 37°C. Visual inspection of the colour changes and reading in BioTek microplate reader at 570nm was performed to determine the Minimum Bactericidal Concentration (MBC). Mean values and standard deviations were calculated. ANOVA followed by Dunnett’s test was performed; p-value of less than 0.05 was considered significant. Results: BRP extract and BRP containing-dentifrice showed antimicrobial activity against S. mutans up to the concentration of 0.3906 μg/mL. The BRP extract and dentifrice showed bactericidal effect at a concentration of 1.5625, but was able to reduce microbial viability at a concentration of up to 0.3906. Parodontax dentifrice showed antimicrobial activity at all dilutions (p< 0.05), presenting a bactericidal effect in the same concentration of the extract (1.5625). It was concluded that all the groups observed had antimicrobial activity against S. mutans. There was no difference between the propolis extract and the common dentifrice. Conclusion: BRP in pure form and processed in a toothpaste shows some antimicrobial activity against S. mutans but less than a commercial toothpaste containing herbal extracts and sodium bicarbonate.Keywords: Propolis, Streptococcus mutans, Dentifrice, Biofilm, Dental decay.

Efficacy of chitosan paste as intracanal medication against Enterococcus faecalis and Candida albicans biofilm compared with calcium hydroxide in an in vitro root canal infection model

BackgroundEnterococcus faecalis and Candida albicans are frequently found in persistent endodontic infection and could remain in dentinal tubules despite intracanal medication with calcium hydroxide (Ca(OH)2), a commonly used medication. Thus, an effective and safe antimicrobial medication against such refractory infection is necessary in endodontic retreatment, so we aimed to test the efficacy of chitosan paste against these microorganisms compared with Ca(OH)2 in root canals of extracted human teeth.MethodsThirty-six sterilized human root samples prepared from extracted premolars and upper maxillary incisors were infected with E. faecalis for 14 days, while 32 were infected with C. albicans for 48 h, for mature biofilm formation. The samples were assigned to 6 groups of intracanal medications: Group 1: no medication (negative control); Group 2: 20% Polyethylene glycol (PEG); Group 3: 20% Propylene glycol (PG); Group 4: Ca(OH)2; Group 5: Chitosan + PEG; and Group 6: Chitosan + PG. After 7 days, intracanal surface dentin was harvested using Protaper next, resuspended, serially diluted and spread on Brain–Heart-Infusion agar (for E. faecalis) and Yeast Extract-Peptone-Dextrose agar (for C. albicans) for colony count. Antimicrobial efficacy was determined as percentage of remaining colony forming unit (CFUs) relative to negative control and analyzed using One-way ANOVA and post-hoc Games-Howell test. The significance level was set at 0.05.ResultsFor E. faecalis, chitosan + PG had significantly higher antibacterial activity than Ca(OH)2 (P = 0.039). Chitosan + PEG and chitosan + PG medication significantly reduced viable bacteria compared with negative control, PEG and PG (P = 0.001, 0.003, 0.024, respectively for chitosan + PEG; P = 0.002, 0.003, 0.014, respectively for chitosan + PG). For C.albicans, chitosan + PEG and chitosan + PG were not significantly different from Ca(OH)2. However, Chitosan + PEG and chitosan + PG, but not Ca(OH)2, showed a significantly lower level of remaining CFUs compared with negative control (P = 0.013 and 0.005, respectively).ConclusionChitosan paste showed better efficacy in reducing viable E. faecalis biofilm when compared to Ca(OH)2 after 7-day intracanal medication in this in vitro root canal model. It could also significantly reduce viable C. albicans, but was not significantly different from Ca(OH)2.

A putative siderophore receptor of Gallibacterium anatis 12656-12 under Fur control also binds hemoglobin.

Pasteurellaceae family members obtain iron directly from host proteins or through siderophore-dependent mechanisms. Although Gallibacterum anatis expresses different virulence factors, its response to growth under iron restriction is unknown. G. anatis cultured in the presence of 2,2′-dipyridyl, up-expressed an approximately 65 kDa protein and repressed the expression of a 70 kDa protein. MALDI-TOF analysis of those proteins indicated homology with CirA (65 kDa), a protein involved in iron-siderophore acquisition in Mannheimia succinoproducens and a TonB-dependent receptor (70 kDa protein), a protein that binds chicken hemoglobin; however, G. anatis siderophore production was not detected by chromo azurol S (CAS)-BHI agar determination. This putative G. anatis siderophore receptor is under Fur control, but not the hemoglobin binding protein, as observed in G. anatis 12656-12 fur mutant (Ω fur 126.13) grown in the presence or not of 2,2′-dipyridyl. The addition of FeCl3 to the culture medium diminished the growth and biofilm production in approximately 30% and 35%, respectively, in the wild-type strain, but the growth of Ω fur 126.13 strain was not affected and biofilm production increased in 35%. G. anatis Ω fur 126.13 presented lower virulence when it was inoculated to 35-day-old chickens in comparison to the wild-type strain. The induction of more than one iron uptake mechanism could benefit pathogenic microorganisms such as Gallibacterium.

MICROBIOLOGICAL PROFILE OF SIGNIFICANT PATHOGENICT BACTERIA PRESENT ON MOBILE PHONES OF HEALTHCARE WORKERS THAT CAUSE NOSOCOMIAL INFECTION

Background: Mobile phones of HCWs play an important role in transmission of infection to patients and also to the health care workers, which can increase the burden of heath care. We planned this study to identify the microbiological prole of signicant pathogenic bacteria present on mobile phones of healthcare workers that cause nosocomial infection and also to assess the usefulness of 70% isopropyl alcohol for decontamination of mobile phones . Methods: 50 Heathcare workers were include in this study. 50samples were collected before decontamination and 50 samples were collected after decontaminated with 70% isopropyl alcohol. Totally 100 samples collected. samples were inoculated in the brain heart infusion broth and incubated at 370C for 24- 48 hours. Samples showing growth were further sub cultured on Blood agar and MacConkey agar. The plates were then be incubated at 37˚C for 24 hours and observed for the growth. Different biochemical tests were used for further identication. Antimicrobial susceptibility test was done according to the Clinical Laboratory Standards Institute guidelines using the Kirby-Bauer disc diffusion method. Results: Among the 50healthcare workers,38 healthcare workers mobile phones were contaminated before decontamination.After decontamination,12 healthcare workers mobilephone were contaminated.

A Bacillus cereus NY5 strain from tilapia intestine antagonizes pathogenic Streptococcus agalactiae growth and adhesion in vitro and in vivo

Bacillus cereus NY5 is a potential probiotic isolated from healthy tilapia (Oreochromis niloticus) gut. In this study, the antagonism of this bacterium against pathogenic Streptococcus agalactiae WC1535 from tilapia was evaluated in vitro and in vivo. Through antagonistic culture, artificial infection, histological micro- and ultramicroscopic detection, and gene expression monitoring, the ability of NY5 to inhibit the growth of WC1535, attenuate its ability to invade tilapia tissue, promote immune cell secretion, and affect host immune gene expression were studied. When NY5 and WC1535 were co-incubated in BHI (brain-heart infusion) or LB (Luria-Bertani) medium, NY5 effectively inhibited the growth of WC1535. Under immersion infection, NY5 attenuated the ability of WC1535 to adhere to the body surface of fish. In oral infection, NY5 effectively inhibited WC1535 from invading tilapia cells, increased the number of goblet cells in the midgut epidermis, and improved the fish survival rate. Moreover, NY5 increased the mitochondria in the midgut of S. agalactiae-infected tilapia. Under oral infection for 20 h, the relative expression levels of the immune-related genes GATA3, LgM, 1L-10, TCR-β, TNF, and TP3 were higher in tilapia treated with WC1535 than in tilapia treated with both NY5 and WC1535 (NY5-WC1535) and with NY5. The MHCII and TGF-β expression levels were higher in the NY5-WC1535 and NY5 treatments (p < 0.05), and the CD4 and MHCI expression levels were higher in WC1535 and NY5-WC1535 treatments (p < 0.05). These results indicate that B. cereus NY5 can effectively reduce tilapia mortality under S. agalactiae infection. The main antagonistic mechanism appears to be inhibiting the growth of S. agalactiae through nutrient deprivation or by secreting extracellular products and reducing its ability to invade and infect. Antagonism was also achieved by modulating specific and non-specific immunity in tilapia infected with S. agalactiae. The findings suggest that B. cereus NY5 may be a potential bacterial antagonist for controlling S. agalactiae infections in tilapia aquaculture.

Fitness cost conferred by the novel erm(51) and rpoB mutation on environmental multidrug resistant-Rhodococcus equi

Rhodococcus equi is a common cause of severe pneumonia in foals. Emergence of macrolide-resistant R. equi isolated from foals and their environment has been reported in the United States. A novel erm(51) gene was recently identified in R. equi in soil from horse farms in Kentucky. Our objective was to determine the effect of the erm(51) gene and associated rpoB mutation on the fitness of multidrug resistant-R. equi (MDR-R. equierm(51)+, rpoB+) under different nutrient conditions. Bacterial growth curves were generated for 3 MDR-R. equierm(51)+, rpoB+ isolates and 3 wild-type (WTN) R. equi isolates recovered from environmental samples of farms in central Kentucky. Growth was measured over 30.5 h in brain-heart infusion broth (BHI), minimal medium (MM), and minimal medium without iron (MM-I). All isolates had significantly (P < 0.05) higher growth in BHI compared to either MM or MM-I. MDR-R. equierm(51)+, rpoB+ exhibited significantly lower growth compared to WTN isolates in BHI (nutrient-rich condition), but not in either MM or MM-I (nutrient-restricted conditions). This study indicates that under nutrient-rich conditions fitness of MDR-R. equierm(51)+, rpoB+ is reduced relative to susceptible isolates; however, under nutrient-restricted conditions MDR-R. equierm(51)+, rpoB+ isolates grow similarly to susceptible isolates. These findings indicate that MDR-R. equierm(51)+, rpoB+ might be outcompeted by susceptible isolates in nature when practices to reduce antimicrobial pressure, such as reducing antimicrobial use in foals, are implemented. But it also raises the concern that these resistant genotypes might persist in the environment of horse-breeding farms in the face of selective pressures such as antimicrobials or nutrient restriction.

Comparison of antimicrobial efficacy of chemical mouthwash and herbal mouthwash

Background: The use of mouth rinse for oral hygiene maintenance has been advocated as an adjuvant to mechanical aids of plaque removal. The aim of this study was to compare the antimicrobial effect of herbal and chemical mouth rinse on bacterial accumulation on orthodontic arch wires. Materials and Methods: The study sample consisted of 15 numbers of 0.016 Nickel Titanium (NiTi) arch wires removed from patients' mouths, which were split into three segments of 1 cm each. Wires were dipped in solutions of Chlorhexidine (Group A), Befresh Herbal (Group B) and Distilled water (Group C) individually for 30 seconds and then in normal saline for one minute. 0.5microlitre of this saline solution was inoculated in a Brain heart infusion medium (BHI) for 24 hours and then examined for bacterial count. The obtained results were subjected to One-way ANOVA, Bonferroni and post hoc tests for statistical analysis. Results: Group A showed the maximum reduction in the bacterial colony forming units (CFU) after 24 hours with a mean value of 65.67cfu. Group B showed a mean value of 336.87cfu. There was a statistically significant difference between the Chlorhexidine group and the Control group.

Growth Kinetics of Listeria monocytogenes on Cut Red Cabbage

Listeria monocytogenes is a foodborne pathogen associated with fresh produce vectors such as leafy greens. Recent outbreaks and recalls associated with red cabbage-containing salads have brought attention to this food commodity. Although data on the proliferation of L. monocytogenes are available for different varieties of whole and cut white cabbage, no information is available on the fate of this pathogen on red cabbage. The aim of this study was therefore to explore the survival of L. monocytogenes on cut red cabbage (Brassica oleracea L. var. capitata f. rubra) during storage at different temperatures. Red cabbage was cut into pieces (5 by 4 cm) and spot inoculated with a six-strain cocktail of rifampin-resistant L. monocytogenes, resulting in an initial inoculation level of 4 log CFU/g. Samples were stored at 5 or 10°C for 14 days or at 25°C for 7 days. At intervals during storage, L. monocytogenes was enumerated by homogenization of cabbage with Butterfield's phosphate buffer, and serial dilutions were plated onto brain heart infusion agar supplemented with rifampin. No growth of L. monocytogenes was observed on cut red cabbage during storage at 5°C, and only minimal proliferation was observed at the higher temperatures. Significant population increases of 0.58 and 1.07 log CFU/g were determined after 3 days of storage at 10 and 25°C, respectively; however, a significant decrease of 0.77 log CFU/g from 3 to 14 days was also observed at 10°C. The modeled growth rates for L. monocytogenes on cut red cabbage stored at 5 and 10°C were 0.11 ± 0.03 and 0.27 ± 0.07 log CFU/g/day, with calculated times to a 1-log CFU/g increase of 9.51 and 3.70 days, respectively; however, L. monocytogenes did not achieve a 1-log increase at either temperature in this study. At 25°C, the modeled growth rate of L. monocytogenes on cut red cabbage was 1.15 ± 0.36 log CFU/g, leading to a calculated and an observed 1-log increase in 0.87 and 3.00 days, respectively. Results from this study aid in understanding the fate of L. monocytogenes on cut red cabbage during storage at different temperatures.

Inhibitory activity of an emulsifying salt polyphosphate (JOHA HBS®) used in processed cheese: An in vitro analysis of its antibacterial potential

In the present study, the inhibitory activity of a commercial polyphosphate (JOHA®️ HBS) was tested in vitro against 21 bacterial strains. Firstly, the antimicrobial activity of JOHA®️ HBS, at different concentrations (from 0.5 to 2.0%) was evaluated in different agar and broth media (namely, Brain Heart Infusion: BHI; Nutrient: NT; Plate Count: PCA; Trypticase Soy: TSA/B), using streak assay (agar) and culture enumeration (broth). Furthermore, the bacterial inhibition of JOHA®️ HBS (at different concentrations, from 0.2% to 3.0%) was evaluated both on NT agar and broth medium, by streak assay, agar-spot method, and by spot-on-the-lawn and well-diffusion method. Finally, the JOHA®️ HBS antimicrobial activity was tested on NT agar at pH 6.3. Results of the streak assay on NT agar showed that 11 out the 21 tested strains were highly inhibited at 0.5% of JOHA®️ HBS. Interestingly, at adjusted pH levels, JOHA®️ HBS concentrations of 1.0% (w/v) were able to inhibit the same targets, confirming the antimicrobial effect of JOHA®️ HBS. This study reveals that NT medium and agar-based tests are required to properly test the inhibitory activity of polyphosphates. Furthermore, results confirmed the antimicrobial activity of JOHA®️ HBS, at low concentrations, against target bacteria of interest to the dairy industry.

Dual-functional adhesive containing amorphous calcium phosphate nanoparticles and dimethylaminohexadecyl methacrylate promoted enamel remineralization in a biofilm-challenged environment

ObjectiveThe cariogenic biofilm on enamel, restoration, and bonding interface is closely related to dental caries and composite restoration failure. Enamel remineralization at adhesive interface is conducive to protecting bonding interface and inhibiting secondary caries. This study intended to assess the remineralization efficiency of adhesive with dimethylaminohexadecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP) on initial caries lesion of biofilm-coated enamel. MethodsArtificial initial carious lesion was created via 72-hour immersion in demineralization solution and cariogenic biofilm was formed after 24-hour culture of Streptococcus mutans (S. mutans). Specimens were then divided into 4 groups: enamel control, enamel treated with NACP, DMAHDM and NACP+DMAHDM respectively. Samples next underwent 7-day cycling, 4 h in BHIS (brain heart infusion broth containing 1 % sucrose) and 20 h in AS (artificial saliva) per day. The pH of BHIS was tested daily. So did the concentration of calcium and phosphate in BHIS and AS. Live/dead staining, colony-forming unit (CFU) count, and lactic acid production of biofilms were measured 7 days later. The enamel remineralization efficiency was evaluated by microhardness testing and transverse microradiography (TMR) quantitatively. ResultsEnamel of NACP+DMAHDM group demonstrated excellent remineralization effectiveness. And the NACP+DMAHDM adhesive released a great number of Ca2+ and PO43- ions, increased pH to 5.81 via acid neutralization, decreased production of lactic acid, and reduced CFU count of S. mutans (P < 0.05). SignificanceThe NACP+DMAHDM adhesive would be applicable to preventing secondary caries, strengthening enamel-adhesive interface, and extending the lifespan of composite restoration.