RESUMEN

Aims: The aim of the study was to compare the activity of sodium hypochlorite (NaOCl) against Enterococcus faecalis when used with four different irrigation protocols. Methodology: Sixty-five single-rooted mandibular premolars with closed apex were prepared till size 35/0.04. The specimens were sterilized and infected with E. faecalis colonies that were cultured separately. The canals were randomly divided into four experimental groups based on irrigation activation protocol, with each group having 15 specimens each - Group 1: control, Group 2: manual dynamic agitation (MDA), Group 3: passive ultrasonic irrigation (PUI), Group 4: intracanal heating (ICH), and Group 5: passive ultrasonic irrigation followed by ICH (PUI ICH). The dentinal shavings were collected and sampled before (S1) and after (S2) the different irrigation techniques were performed. The colony-forming units were counted, and the bacterial reduction was calculated for each group. Results: A significant reduction in the number of E. faecalis colonies was observed for all the experimental groups (P < 0.001). The groups with ICH of NaOCl showed a considerable reduction in bacterial colonies than other groups (P < 0.001), with Group 5 that combined ultrasonics with ICH showed the highest reduction. Conclusion: ICH of NaOCl may be used as an adjunct to root canal irrigation to reduce the bacterial concentration from root canal spaces.

RESUMEN

OBJECTIVE: Wide inter-individual variations in ionizing radiation (IR) responses of neonatal hematopoietic system calls for identifying reliable biomarkers to effectively estimate radiation exposure damages in neonates. METHODS: Association between telomere length (TL) at birth and radiation sensitivity of cord blood hematopoietic stem cells (HSC) from 166 healthy newborns were investigated by assessing their clonogenic differentiation. TL was determined as terminal restriction fragment (TRF) by Southern blot method. RESULTS: TL correlated with surviving fractions of total progenitor colony forming cell (CFC) content at 0.75 Gy (p < 0.05), granulo-macrophagic lineage colony forming units (CFU-GM) at 0.75 Gy (p < 0.05) and erythroid burst forming unit (BFU-E) at 0.75 Gy (p < 0.05) & at 3 Gy (p < 0.05) of newborns. CONCLUSION: Our results indicate risks for HSC clonogenic survival in neonates with shorter telomeres after IR exposure. These observations might aid in considering TL at birth as an assessment factor for radiation related hematopoietic challenges in children.

RESUMEN

Integrated pest management (IPM) is a comprehensive approach to managing diseases, focusing on combining various strategies to reduce pathogen populations effectively and in an environmentally conscious way. We investigated the effects of IPM on beneficial microbial populations and its relationship with pathogen populations in both direct-seeded rice (DSR) and transplanted rice (TR) systems. This study demonstrates that IPM practices have significantly higher populations of beneficial microbes, such as Trichoderma harzianum and Pseudomonas fluorescens, and lower level of the pathogen Fusarium verticillioides compared to non-IPM (farmer practices). The average mean population of T. harzianum was 6.38 × 103 CFU/g in IPM compared to 3.22 × 103 CFU/g in non-IPM during 2019 in TR at Bambawad. P. fluorescens mean population in 2019 was significantly higher in IPM (4.67 × 103 CFU/g) than in non-IPM (3.82 × 103 CFU/g) at the Karnal location in DSR. The F. verticillioides populations were significantly lower in IPM fields (9.46 × 103 CFU/g) compared to non-IPM fields (11.48 × 103 CFU/g) during 2017 at Haridwar in TR. Over three years, a significant increase in the populations of beneficial microbes in IPM plots was observed in all three locations of both TR and DSR, highlighting the sustainable impact of IPM practices. Disease dynamics analysis revealed that IPM effectively managed key diseases in both DSR and TR systems, with significant correlations between microbial density and disease severity. A significant positive correlation was recorded between F. verticillioides population and bakanae incidence at all three locations. Sheath blight incidence was negatively correlated with P. fluorescens population in both TR and DSR. In DSR, bacterial blight and brown spot diseases are reduced with the increased population of T. harzianum. Bioagents T. harzianum and P. fluorescens reduced disease incidence, underscoring the role of beneficial microbes in disease suppression and their importance for sustainable production using IPM practices.

RESUMEN

BACKGROUND: Currently for diagnosing Mycobacterium tuberculosis and its drug resistance, two sputum samples are required. One of them is subjected to TrueNat™ and if positive the other sample is subjected to line probe assay (LPA). This study was done to evaluate whether TrueNat extracted DNA can be directly used for performing LPA in a diagnostic laboratory setting to decrease patient turn-around time. METHODS: Total 45 smear positive sputum samples were subjected to TrueNat™ MTB detection and first and second line (FL and SL) LPA testing in parallel. DNA extracted by Trueprep® Cartridge was also tested by LPA and results were compared. Further, TrueNat extracted DNA from 20 samples was divided into 6 aliquots each, two of which were stored at 4 °C, 37 °C and 55 °C (under humidification) each. One aliquot from stored DNA at each temperature was used for FL & SL LPA on day three and the other on day eight. The blots thus obtained were compared with those of conventional LPA at day 1. RESULTS: For FL-LPA, TrueNat extracted DNA gave valid results for all 45 (100%) samples but conventionally extracted DNA could give results for 44 (97.8%) samples. Likewise, for SL-LPA, valid results were obtained for 40 (88.9%) and 35 (77.8%) samples respectively using TrueNat extracted DNA and conventionally extracted DNA respectively. All samples with invalid LPA results had Ct values ≥ 28 by TrueNat PCR. LPA results were obtained for all the 20 samples using stored DNA at all temperatures and duration. CONCLUSIONS: TrueNat extracted DNA can be used for performing LPA under field conditions for selected samples.

Asunto(s)

RESUMEN

Introduction: Complex anatomy of the root canal system results in incomplete debridement with mechanical instrumentation, leaving some areas or root canal walls untouched. There comes the significance of endodontic irrigants with residual antibacterial substantivity which prolongs the post-antibiotic effect, thereby improving the success and predictability of endodontic treatment. Aim: To comparatively evaluate the residual antibacterial substantivity of 2% chlorhexidine, Biopure MTAD and 2% chitosan against Enterococcus faecalis at intervals of 1, 14 and 28 days. Materials and Methods: Seventy-five therapeutically extracted permanent single rooted mandibular premolars teeth were selected. Dentin blocks of 4 mm thickness were prepared and enlarged to 1.6 mm. The autoclaved blocks were inoculated with 24-hour colonies of pure cultures of E. faecalis for 14 days. After the contamination period, canals of each dentin block were irrigated with 5 ml of sterile saline and dried with sterile paper points. A total of 75 dentin blocks were randomly divided into five groups as follows: Group A (21 specimens): 2% chlorhexidine, Group B (21 specimens): Biopure MTAD, Group C (21 specimens): 2% chitosan, Group D (6 specimens): positive control (infected dentin tubes) and Group E (six specimens): negative control (sterile dentin tubes). Then, the lumens of dentin blocks were irrigated with the respective irrigants for 10 mins and were dried using sterile paper points. The specimens were then incubated at 37°C for 28 days to maintain humidity. At experimental intervals of 1, 14 and 28 days, dentin shavings were removed from the canals of respective groups by circumferential filing with sterile no. 35 Hedstrom files. The powdered dentin samples obtained with each dentin block were observed for colony forming units (CFUs) using a Digital Colony counter and were expressed as CFUs/mL. Result: All the irrigants in the study showed a significant decrease in CFUs from day 1 to day 28 indicating that they have residual antibacterial substantivity against E. faecalis. Group B (Biopure MTAD) showed significantly least mean CFUs compared to Group A (2% CHX) and Group C (2% chitosan) against E. faecalis at B1(day 1), B2(day 14) and B3(day 28). Group A (2% CHX) showed significantly higher mean CFUs than Group C (2% chitosan) at A1(day 1). Group C (2% chitosan) showed significantly higher mean CFUs compared to Group A (2% CHX) at C2(day 14) and C3 (day 28). Conclusion: MTAD showed statistically higher residual antibacterial substantivity against E. faecalis at experimental periods of 1, 14 and 28 days. The residual antibacterial effect of 2% chitosan was better compared to 2% CHX at day 1. The residual antimicrobial substantivity of 2% CHX was higher compared to 2% chitosan at intervals of 14 and 28 days.

RESUMEN

OBJECTIVES: Ultrasonic scaling is extensively applied as part of the initial therapy for periodontal diseases, which has been restricted since the outbreak of the COVID-19 pandemic due to droplets and aerosols generated by ultrasonic devices. An extraoral scavenging device (EOS) was designed for diminishing droplets and aerosols in dental clinics. The objective of this study is to evaluate the effect of EOS on eliminating droplets and aerosols during ultrasonic supragingival scaling. METHODS: This single-blinded, randomised controlled clinical trial enrolled 45 patients with generalised periodontitis (stage I or II, grade A or B) or plaque-induced gingivitis. The patients were randomly allocated and received ultrasonic supragingival scaling under three different intervention measures: only saliva ejector (SE), SE plus EOS and SE plus high-volume evacuation (HVE). The natural sedimentation method was applied to sample droplets and aerosols before or during supragingival scaling. After aerobic culturing, colony-forming units (CFUs) were counted and analysed. RESULTS: Compared with the level before treatment, more CFUs of samples throughout treatment could be obtained at the operator's chest and the patient's chest and the table surface when using SE alone (p < 0.05). Compared with the SE group, the SE + EOS group and the SE + HVE group obtained decreasing CFUs at the operator's chest and the patient's chest (p < 0.05), while no significant difference was determined between these two groups. CONCLUSIONS: The EOS effectively eliminated splatter contamination from ultrasonic supragingival scaling, which was an alternative precaution for nosocomial contamination in dental clinics.

RESUMEN

Background The purpose of this in vitro investigation was to evaluate the impact of five distinct commercial mouthwashes on the development of Candida albicans that had been adhered to heat-cured acrylic resin sheets. Methods This in vitro investigation was carried out at the MES Medical College's Microbiology Department in Perinthalmanna, Kerala, India. A total of 72 heat-cured acrylic resin sheets, size 10 × 10 × 2 mm, were fabricated. After disinfection, all 72 acrylic sheets were placed in a flask containing a suspension of the standard strain of Candida species (American Type Culture Collection) and incubated at 37ºC for 24 hours. Then, the acrylic sheets were randomly divided into six groups, with each group containing 12 acrylic sheets. Group 1 was the control group to which no mouthwash was added. In group 2, Colgate Plax was added. In group 3, Hiora Himalaya was added. In group 4, Oral B was added. In group 5, Listerine was added. In group 6, Pepsodent was added. Colony-forming units (CFUs) were assessed using a colony counter every six, 24, 48, and 120 hours. After obtaining the pH and CFU of all 72 specimens, software known as the Statistical Package for Social Sciences (SPSS) (IBM Corp., Armonk, NY) was used to analyze the data. Results Candida albicans adhered to heat-cured denture base acrylic resin sheets differed significantly in response to commercially available mouthwashes (Oral B, Colgate Plax, and Pepsodent) and non-commercial mouthwashes (Hiora Himalaya and Listerine) that contained cetylpyridinium chloride. Conclusions Compared to other mouthwashes that do not contain cetylpyridinium chloride (Listerine and Hiora Himalaya), mouthwashes with cetylpyridinium chloride as the active ingredient (Oral B, Pepsodent, and Colgate Plax) have shown good antifungal properties against the adhering Candida albicans on denture base resin.

RESUMEN

The need for controlling bacteria and pain during root canal therapy is undeniable. This clinical trial aimed to assess whether there is a difference in colony-forming unit (CFU) reduction after instrumentation and post-endodontic pain after root canal treatment (RCT) using a traditional endodontic cavity (TEC) versus a conservative endodontic cavity (CEC). This clinical study was conducted on 89 patients designated for a single-visit RCT. Patients were allocated randomly (TEC n = 45 and CEC n = 44). The access opening was gained accordingly in each group by a single operator. A pre-instrumentation sample of root canal dentin was collected using an endodontic file; the second sample was collected similarly, right after shaping and cleaning the root canal. The CFU was calculated based on the samples collected. The pain level was recorded preoperatively and at 1, 7, and 21 days postoperatively utilizing a visual analog scale (VAS). There were no statistically significant differences in the CFU reduction between the TEC and CEC groups (p > 0.05). Additionally, there were no statistically significant differences found in postoperative pain levels between the TEC and CEC at 1, 7, and 21 days (p > 0.05). Despite the limitations of this study, both the CEC and TEC demonstrate a decrease in bacteria within the root canals and alleviate postoperative pain with no difference between them.

RESUMEN

Aim: The study evaluated the antifungal activity of sodium hypochlorite (NaOCl), calcium hypochlorite (Ca(OCl)2), and modified salt solution (MSS) assisted with passive ultrasonic irrigation against Candida albicans. Materials and Methods: One hundred and thirty-six single-rooted premolars were decoronated and enlarged up to a file #45, autoclaved, inoculated with C. albicans, and incubated for 72 h. The samples were randomly distributed into eight groups (n = 17) according to the protocol for decontamination G1: No treatment, G2: Distilled water (DW), G3: 2.5% NaOCl, G4: 2.5% NaOCl + ultrasonic activation (US), G5: 2.5% Ca(OCl)2, G6: 2.5% Ca(OCl)2 + US, G7: MSS, G8: MSS + US. Microbiological testing (Colony forming Unit [CFU] counting) was performed before and after the treatment. Statistical Analysis: Data were subjected to the one-way analysis of variance followed by the Tukey's post hoc test (P < 0.05). Results and Conclusion: Groups 1 and 2 showed the highest mean contamination (5.41 and 4.31 log10 CFU/mL, respectively), which was statistically different from all the other groups (P < 0.001). G4 showed the lowest mean contamination (0.24 log10 CFU/mL) with statistically significant value (P < 0.001). 2.5% NaOCl with ultrasonic activation can aid in significant fungal reduction. Ultrasonic activation of 2.5% NaOCl, 2.5% Ca(OCl)2, and MSS was also found to have improved antifungal activity against C. albicans.

RESUMEN

BACKGROUND: Denture stomatitis, frequently encountered, is generally addressed symptomatically, with limited exploration of preventive approaches involving antifungal medicinal plants. OBJECTIVE: This study assessed the impact of Artemisia sieberi extracts on the candida growth of conventional and digitally processed acrylic materials. METHOD: Thirty acrylic resin discs (3 mm thickness × 10 mm diameter) were prepared by conventional or CAD/CAM technology (milling and 3D printing). The resin discs were exposed to simulated brushing, thermocycling, and immersion in Artemisia sieberi extract for 8 hours. The surface roughness of the discs was assessed at baseline and after immersion in Artemisia sieberi extract. Candida growth was quantified through colony-forming units (CFU/mL). Data was analyzed using SPSS v.22 (α⩽ 0.05). RESULTS: Irrespective of the material type, the post-immersion surface roughness was significantly higher compared to pre-immersion values (p< 0.05). Candida growth was significantly higher in conventional acrylic materials than digitally fabricated acrylics (p< 0.05). At × 3, Ra and CFU were found to be moderately positive and non-significantly correlated (R= 0.664, p= 0.149). At × 4, Ra and CFU were found to be weak positive and non-significantly correlated (R= 0.344, p= 0.503). CONCLUSION: Artemisia sieberi extracts had a notable impact on digitally fabricated denture acrylics, reducing candida albicans growth compared to conventional heat-cured acrylic. This suggests a potential role for these extracts in improving denture hygiene and preventing denture stomatitis, particularly in the context of digitally fabricated dentures.

Asunto(s)

RESUMEN

Background: Endodontic infections have been clearly described as biofilm-mediated infections. Bacteria and their by-products have been known to cause these infections. With the introduction of new drugs and the use of nanoparticles in recent times, there has been a significant reduction in the bacterial load in endodontic infections. Aims and Objectives: The in vitro study focuses on checking the antibacterial efficacy of silver nanoparticles and its combination with other medicaments against the root canal pathogen - Enterococcus faecalis (E. faecalis). Methodology: In the present study, 140 extracted human teeth were used. The teeth were sectioned, and biomechanical preparation was done. The root canals of the extracted teeth were inoculated with the culture of E. faecalis. The teeth were divided into six groups based on the intracanal medicament used: Group 1 - Silver nanocure gelGroup 2 - Silver nanocure gel + Cavisept gel (1:1)Group 3 - Silver nanocure gel + Aveu-Cal gel (1:1)Group 4 - Silver nanocure gel + Cavisept gel + Aveu-Cal gel (1:1:1)Group 5 - Positive control (specimens were inoculated with Enterococcus faecalis and left untreated to confirm the presence of infection)Group 6 - Negative control (no bacterial contamination of specimens). The colony-forming units were recorded after 48 h of incubation. Results: The statistical analysis of the colony-forming units was done using the Kruskal-Wallis tests. Silver nanocure gel + Cavisept gel + Aveu-Cal gel (1:1:1) showed the least colony-forming units. Conclusion: The present study is an in vitro study, in which we concluded that the combination of all the intracanal medicaments is the best for the elimination of E. faecalis biofilm from the root canal. The above findings need to be tested in vivo also.

RESUMEN

Lactobacillus species are the main colonizers of the vaginal microbiota in healthy women. Their absolute quantification by culture-based methods is limited due to their fastidious growth. Flow cytometry can quantify the bacterial concentration of these bacteria but requires the acquisition of expensive equipment. More affordable non-culturable methods, such as fluorescence microscopy, are hampered by the small size of the bacteria. Herein, we developed an indirect fluorescence microscopy method to determine vaginal lactobacilli concentration by determining the correlation between surface area bacterial measurement and initial concentration of an easily cultivable bacterium (Escherichia coli) and applying it to lactobacilli fluorescence microscopy counts. In addition, vaginal lactobacilli were quantified by colony-forming units and flow cytometry in order to compare these results with the indirect method results. The colony-forming-unit values were lower than the results obtained from the other two techniques, while flow cytometry and fluorescence microscopy results agreed. Thus, our developed method was able to accurately quantify vaginal lactobacilli.

RESUMEN

Background: Full-coverage restorations are commonly employed choice of treatment in treating multisurface carious lesions in primary teeth. Aim: To assess the amount of Streptococcus mutans (S. mutans) colonization and oral hygiene status in deciduous molars restored with preformed zirconia and stainless steel crowns (SSC). Materials and methods: A total of 21 children aged between 4 and 7 years with bilateral carious primary molars were randomly divided into two groups of zirconia and SSC. Plaque collection was done using sterile swabs at baseline and 1-month intervals. S. mutans was cultured on mitis salivarius-bacitracin agar (MSBA). The microorganisms were then counted and expressed as colony-forming units. The plaque and gingival indices were recorded during the follow-up visits. All data were tabulated and subjected to statistical analysis, with the level of significance set at 5%. Results: A total of 21 children with 42 teeth were randomized into group I-SSC and group II-zirconia crowns using the split-mouth technique, respectively. The zirconia group showed a statistically significant reduction in the adhesion of S. mutans (p < 0.001). On comparing the plaque and gingival indices between the groups, plaque index (PI) and gingival index (GI) scores were significantly low in the zirconia group as compared with the SSC, with a mean difference of 0.08 at 3 months in group II (p < 0.001). Conclusion: Streptococcus mutans (S. mutans) adhesion to zirconia crowns was significantly less when compared with SSC, with better gingival health and oral hygiene. How to cite this article: Elizabeth JAA, Ramkumar H, Paulindraraj S, et al. Evaluation of Streptococcus mutans Colonization and Oral Hygiene Status in Primary Molars Restored with Two Different Crowns: A Randomized Clinical Trial. Int J Clin Pediatr Dent 2023;16(S-2):S183-S189.

RESUMEN

Cellular sensitivity is an approach to inhibit the growth of certain cells in response to any non-permissible conditions, as the presence of a cytotoxic agent or due to changes in growth parameters such as temperature, salt, or media components. Sensitivity tests are easy and informative assays to get insight into essential gene functions in various cellular processes. For example, cells having any functionally defective genes involved in DNA replication exhibit sensitivity to non-permissive temperatures and to chemical agents that block DNA replication fork movement. Here, we describe a sensitivity test for multiple strains of Saccharomyces cerevisiae and Candida albicans of diverged genetic backgrounds subjected to several genotoxic chemicals simultaneously. We demonstrate it by testing the sensitivity of DNA polymerase defective yeast mutants by using spot analysis combined with colony forming unit (CFU) efficiency estimation. The method is very simple and inexpensive, does not require any sophisticated equipment, can be completed in 2-3 days, and provides both qualitative and quantitative data. We also recommend the use of this reliable methodology for assaying the sensitivity of these and other fungal species to antifungal drugs and xenobiotic factors.

RESUMEN

When silica nanoparticles (SiNP) reach the water bodies interact with the already existing pollutants in the environments. This study aimed to evaluate the ecotoxicity of SiNP under the presence/absence of Cu in mosquitofish (Gambusia holbrooki). Fish were exposed to 0, 10 and 100 mg SiNP L-1, alone or mixed with Cu (0.25 mg L-1). After 96 h, the amount of colony forming units (CFU) of bacteria living on the skin mucus was analysed, and oxidative stress, tissue damage enzymes, and neurotoxicity were evaluated. We observed a reduction in CFU when Cu was present in the media. The liver was the target organ, evidencing a decrease in tissue damage enzymatic activities, activation of the antioxidant system in all treatments, and lipid oxidative damage when the SiNP and Cu were mixed. Overall, SiNP ecotoxicity was proved, which could also be enhanced by the presence of ubiquitous elements such as metals.

Asunto(s)

RESUMEN

This study aimed to investigate the effectiveness of combined negative pressure wound therapy (NPWT) and human amniotic membrane in patients with chronic wounds associated with diabetes. A total of five patients with type 2 diabetes, including ischemic and mixed forms of diabetic foot syndrome, presenting with ischemic wounds of the lower extremities were included in this study. Patients with uncorrected limb ischemia were excluded. The treatment protocol included diabetes compensation (treatment with fractional insulin therapy), anticoagulant, metabolic therapy and angiotropic therapy, physical treatment methods, osteoporosis therapy with calcium preparations, and wound-specific interventions. The primary treatment approach involved the application of a vacuum bandage to the transplanted human amniotic membrane, which improved the adaptation of the flap to the wound surface, allowed the removal of excess wound exudate, and stimulated angiogenesis and reparative properties. The combined approach of NPWT and biotherapy was a safe and effective cure for diabetic wounds, promoting faster wound healing, reducing the need for autodermoplasty, and possibly reducing the necessity for high-level amputations.

Asunto(s)

RESUMEN

Hepatocyte-like cells (HLCs) generated from human pluripotent stem cells (PSCs) exhibit hepatocytic properties in vitro; however, their engraftment and functionality in vivo remain unsatisfactory. Despite optimization of differentiation protocols, HLCs did not engraft in a mouse model of liver injury. In contrast, organ-derived hepatocytes reproducibly formed colonies in the liver injury mouse model. As an extension of the phenomenon observed in hematopoietic stem cells giving rise to colonies within the spleen, commonly referred to as "colony-forming units in spleen (CFU-s)", we hypothesize that "colony-forming units in liver (CFU-L)" serves as a reliable indicator of stemness, engraftment, and functionality of hepatocytes. The uniform expression of the randomly inactivated gene in a single colony, as reported by Sugahara et al. 2022, suggests that the colonies generated by isolated hepatocytes likely originate from a single cell. We, therefore, propose that CFU-L can be used to quantify the number of "hepatocytes that engraft and proliferate in vivo" as a quantitative assay for stem cells that utilize colony-forming ability, similar to that observed in hematopoietic stem cells.

Asunto(s)

RESUMEN

AIM: This in vitro study aims to compare the antimicrobial efficacy of triple antibiotic paste, double antibiotic paste, and cefixime-based triple antibiotic paste against Enterococcus faecalis. Materials and methods: Fifty single-rooted, caries-free, permanent teeth without any developmental defects were included in this study. The specimens were divided into five groups, with each group consisting of 10 teeth that received a specific medicament. The groups were as follows: Group I: control; Group II: calcium hydroxide; Group III: triple antibiotic paste; Group IV: double antibiotic paste; and Group V: cefixime-based triple antibiotic paste. The antimicrobial activity of the medicaments was assessed against E. faecalis at the end of the seventh and 14th days. The colony-forming units (CFU) were calculated using the Kolmogorov-Smirnov and Wilcoxon tests. RESULTS: After seven days of the experimental process, it was observed that the CFU count was highest in group I and lowest in group V. In a similar vein, after 14 days, the maximum decrease in CFU count was observed in Group V, while the least reduction in CFU count was observed in Group II. On intergroup comparison, it was found that the maximum decrease in CFU was noted in Group V, followed by Group IV, Group III, and Group II. CONCLUSION: The study results indicated that the cefixime-enriched antibiotic paste had the greatest antimicrobial effectiveness, while the double and triple antibiotic pastes offered superior antibacterial efficacy against E. faecalis at the end of the seventh and 14th days.

RESUMEN

Background Head and neck cancer ranks as the sixth most common cancer globally. Reduced saliva production brought on by postradiation therapy upsets the delicate balance between bacterial load and a weakened immune system. Oral hygiene is commonly neglected in patients who have undergone radiotherapy and they often develop dry mouth, mucositis due to radiation therapy, etc., as side effects. Despite being a part of the current standard, chlorhexidine carries numerous disadvantages such as taste alteration, teeth staining, and dry mouth. An extensive review of the literature demonstrates the antibacterial properties of essential oils (EOs) derived from plant materials, which may be able to prevent the development of such opportunistic microorganisms in the oral cavity. Methodology The cinnamon bark EO and Cajeput EO were procured and checked for their solubility. The final ratio at which the oils were found to be soluble was the 1:1 (w/v) ratio. The minimum inhibitory concentration (MIC) of cinnamon bark oil (Cinnamomum verum) and Cajeput oil (Melaleuca leucadendron) against Staphylococcus aureus, Enterococcus faecalis, and Candida albicans was determined by serial dilution method using Resazurin dye, and the minimum bactericidal concentration (MBC) was done by a spread plating method. The polyherbal mouthwash was subjected to cytotoxicity assay against human gingival fibroblasts. All the experiments were performed in triplicates. Results The overall results showed that cinnamon bark EO had the strongest efficacy against S. aureus (0.33 ± 0.14 mg/mL) and E. faecalis (0.41 ± 0.14 mg/mL), but not against C. albicans (2.85 ± 2.11 mg/mL). Cajeput EO showed the least efficacy against all the groups; whereas the combination of EOs proved to be the most efficacious and showed good antimicrobial activity against these most commonly encountered microorganisms in head and neck cancer postradiotherapy. Conclusions Cinnamon and Cajeput EOs in combination proved to be effective in this in vitro study against the most common microorganisms encountered in patients with head and neck cancer postradiotherapy and are comparable to 0.2% chlorhexidine.

RESUMEN

Establishment of an intracellular niche within mammalian cells is key to the pathogenesis of the gastrointestinal bacterium, Salmonella enterica serovar Typhimurium (S. Typhimurium). Here we will describe how to study the internalization of S. Typhimurium into human epithelial cells using the gentamicin protection assay. The assay takes advantage of the relatively poor penetration of gentamicin into mammalian cells; internalized bacteria are effectively protected from its antibacterial actions. A second assay, the chloroquine (CHQ) resistance assay, can be used to determine the proportion of internalized bacteria that have lysed or damaged their Salmonella-containing vacuole and are therefore residing within the cytosol. Its application to the quantification of cytosolic S. Typhimurium in epithelial cells will also be presented. Together, these protocols provide an inexpensive, rapid, and sensitive quantitative measure of bacterial internalization and vacuole lysis by S. Typhimurium.

Asunto(s)