Reduction In Bacterial Counts Research Articles

Augmenting emergency granulopoiesis with CpG conditioned mesenchymal stromal cells in murine neutropenic sepsis

AbstractPatients with immune deficiencies from cancers and associated treatments represent a growing population within the intensive care unit with increased risk of morbidity and mortality from sepsis. Mesenchymal stromal cells (MSCs) are an integral part of the hematopoietic niche and express toll-like receptors, making them candidate cells to sense and translate pathogenic signals into an innate immune response. In this study, we demonstrate that MSCs administered therapeutically in a murine model of radiation-associated neutropenia have dual actions to confer a survival benefit in Pseudomonas aeruginosa pneumo-sepsis that is not from improved bacterial clearance. First, MSCs augment the neutrophil response to infection, an effect that is enhanced when MSCs are preconditioned with CpG oligodeoxynucleotide, a toll-like receptor 9 agonist. Using cytometry by time of flight, we identified proliferating neutrophils (Ly6GlowKi-67+) as the main expanded cell population within the bone marrow. Further analysis revealed that CpG-MSCs expand a lineage restricted progenitor population (Lin−Sca1+C-kit+CD150−CD48+) in the bone marrow, which corresponded to a doubling in the myeloid proliferation and differentiation potential in response to infection compared with control. Despite increased neutrophils, no reduction in organ bacterial count was observed between experimental groups. However, the second effect exerted by CpG-MSCs is to attenuate organ damage, particularly in the lungs. Neutrophils obtained from irradiated mice and cocultured with CpG-MSCs had decreased neutrophil extracellular trap formation, which was associated with decreased citrullinated H3 staining in the lungs of mice given CpG-MSCs in vivo. Thus, this preclinical study provides evidence for the therapeutic potential of MSCs in neutropenic sepsis.

Impacts of Green Coffee Powder Supplementation on Growth Performance, Carcass Characteristics, Blood Indices, Meat Quality and Gut Microbial Load in Broilers

This work investigated the effect of dietary green coffee powder (GCP) on the growth, body characteristics, antioxidant status, serum metabolites, and meat quality of 308 Ross broiler chickens. A total of 180 non-sexed seven-day old chicks were randomly distributed into three experimental groups. The untreated group received a basal diet (control), while the second and third groups were fed the original diet fortified with 1.25 and 2.5 g GCP/kg, respectively, for four weeks. Results revealed an improvement (p < 0.05) in live body weight in the group fed 2.5 g/kg GCP at five weeks of age compared to the other groups. Broiler Chicks fed the 1.25 g/kg GCP diet showed a more significant decrease in live body weight than the control group at five weeks of age. The GCP supplementation at level 2.5 g/kg GCP enhanced feed conversion ratio at 3–5 and 1–5 weeks of age. Dietary treatments did not affect (p > 0.05) carcass, dressing, and giblets percentages. Different levels of GCP significantly affected the liver, abdominal fat, intestinal length, and lymphoid organs percentages. The changes in serum blood traits and serum oxidative stress markers were not significant among the control and the treated groups. With the increment levels of GCP, results showed elevated values of meat pH, lightness (L*), and redness (a*), as well as a significant decrease in its yellowness (b*). Broilers fed 2.5 g/kg GCP diet showed a significant reduction in the total bacterial count, total yeasts and molds count, Escherichia coli, Enterococcus spp., and Salmonella spp., as well as increasing counts of lactic acid bacteria. The dietary GCP 2.5 g/kg diet supplementation could be used to decrease the pathogenic microorganisms’ populations in the broiler’s gut. The present experiment has shown that in unsexed broiler chickens, green coffee powder at level of 2.5 g/kg improved the live body weight and feed conversion ratio and decreased the pathogenic bacterial count in the gut.

EFFECTIVENESS OF HAND HYGIENE IN REDUCING BACTERIAL FLORA IN HEALTH CARE WORKERS-A STUDY OF IMPACT

Introduction: Hand hygiene is simplest, most effective and least expensive tool to prevent health care worker associated infection. The compliance among HCW is low due to various reasons leading to increased morbidity and mortality in Healthcare associated infection (HAI). Proper hand hygiene significantly reduces bacterial flora and HAI. The study was planned with the aim to know the pattern of microbial flora and its drug resistance and effectiveness of hand hygiene in reducing bacterial load on hands of health care workers. Material and Methods: Both hand finger imprints of 50 participants were taken on Blood agar before and after hand hygiene. The plates were incubated 24-48 hours at 37°C.Colony count was done. Bacteria were identified by their colony characteristics and biochemical reactions. AST was performed as per CLSI 2019 guidelines. Results: 90-99% reduction in bacterial colony count after hand hygiene was seen in majority of participants Mixed growth was seen in ten samples. Micrococcus was most common organism isolated in twenty-four samples, followed by diptheroids in sixteen samples, Coagulase negative staphylococcus (CoNS) in fourteen samples and Staphylococcus aureus in six samples .Three CoNS and four Staphylococcus aureus were Methicillin resistant. Gram negative bacilli isolated were Klebsiella species, Pseudomonas species and Escherichia Coli each in two samples respectively One Escherichia Coli was ESBL producer. All the GNB were sensitive to carbapenem. After performing hand hygiene micrococcus was isolated from four sample, diptheroids from three and CONS from one sample. Staphylococcus aureus and GNB were not found after hand hygiene Conclusion: HCW hands are colonized with bacteria. Proper hand hygiene technique awareness and its compliance significantly reduce bacterial load and decrease HAI.

Evaluation of the Antibacterial efficacy of newly formulated Nano Triple Antibiotic paste with Nano Anti-inflammatory drug as a root canal medicament. (A double blind randomized clinical trial)

Intracanal microorganisms' elimination is essential for root canal treatment long-term success. Proper mechanical preparation and irrigation in conjugation with intracanal medicaments can achieve this goal. The aim of this study was to evaluate the ability of Nano triple antibiotic paste with Nano diclofenac potassium anti-inflammatory drug (Nano TAPC) versus regular Triple antibiotic paste with diclofenac potassium anti-inflammatory drug (TAPC) and Calcium hydroxide (Ca (OH)2 ) used as intra-canal medication in reducing intracanal bacterial count. Methods: 60 patients with upper central incisors were chosen (all necrotic and asymptomatic) and then they were divided into three groups according to the intra-canal medication used: Ca (OH) 2, TAPC and Nano TAPC. Access cavity was performed for the targeted teeth followed by root canals preparation using rotary Protaper Next files with saline irrigation. Bacteriological samples were obtained from the root canals before (S1) and after instrumentation (S2) in the first treatment session. Subsequently, intracanal medication was placed and bacterial reduction was assessed in the second session after 3 days (S3) using colony forming unit test. Results: There was a statistically significant bacterial count reduction in all groups from S2 to S3. Nano TAPC intracanal medication achieved significant bacterial count reduction compared to that of TAPC intracanal medication and Ca (OH) 2. Conclusion: NTAPC as intracanal medication was more effective in reducing the root canal total bacterial count than that of the TAP and that of the Ca (OH) 2 in asymptomatic uniradicular necrotic teeth.

GROWTH INHIBITORY EFFECT OF CHLORHEXIDINE AND HEXETIDINE CONTAINING-MOUTHWASHES AGAINST ORAL BACTERIAL ISOLATES

Background
 Frequent use of mouthwash (MW) is one of the most effective methods used to prevent oral bacterial infections and to assist individuals in their efforts to achieve and maintain better oral health. Using a MW containing antibacterial agents would be a simple way to prevent growth and multiplication of pathogenic organisms in oral cavity causing dental caries and other mouth diseases. Chlorhexidine (CHX) and Hexetidine (HX) have been proposed as potent biocides against oral bacteria.
 Objective
 The present study was performed to investigate oral bacteria growth inhibition when using any of four mouthwashes that are commercially available in the Libyan market and contain either CHX, (Zordy land Oraxin), or HX, (Hextril and Givalex), and to clarify whether CHX and HX were suitable and safe biocides that can be included in mouthwash products.
 Materials and Methods
 Sixty adult (45 females and 15 males) volunteers had been chosen and divided into four groups and their saliva samples were assessed for microbial count at the beginning and the end of two weeks of treatment, during which they rinsed with 15ml of mouthwashes for 30 seconds twice a day (morning and evening) in addition to their usual oral hygiene procedures. The antibacterial activity of mouthwashes was assayed by cell viable count technique and cell diffusibility measurement.
 Results
 The results showed wide variations in the effectiveness of mouthwashes; those containing CHX were more effective (P ≤0.05) than formulations containing HX on oral microbial count. The main findings of the present study were that Zordyl, Oraxinand Hextril exerted high effects on the salivary microbiota, causing 90%, 60% and 34% reduction in salivary bacterial counts respectively. 25% reduction was observed for Givalex. On the other hand, the zone of inhibition test showed that Zordyl and Oraxin had large zone inhibitory effects, while Hextril and Givalex, were less effective on some bacterial species.
 Conclusion
 It can be concluded that twice daily use of CHX mouthwash (CHX-MW) or HX mouthwash (HX-MW) reduces oral bacterial load counts in healthy subjects when used as an adjunct to their normal oral hygiene procedures. This also suggests that inhibitory power of mouth washes containing CHX is greater on oral bacteria than mouthwashes containing HX.

Decontamination of rough implant surfaces colonized by multispecies oral biofilm by application of leukocyte- and platelet-rich fibrin.

Decontamination of biofilm-infected rough implant surfaces is challenging. Platelet rich blood products have been shown to have anti-microbial properties against periodontal pathogens. Our aim was to investigate the effect of a potential biological implant surface disinfectant, leukocyte- and platelet-rich fibrin (L-PRF), on a mature oral multispecies biofilm on a rough titanium surface. Sandblasted, large grit, acid-etched (SLA) titanium disks were inoculated with subgingival dental plaque and cultured anaerobically for 21 days. The L-PRF membranes were collected from 12 donors in three trials (four donors in each trial). The disks were rinsed with 0.9% NaCl and exposed to the cell-rich portion of the L-PRF membranes for 48hours followed by scanning electron microscope (SEM) analysis immediately or after rinsing with 0.9% NaCl prior to fixation. The presence of platelet factor-4 in the rinse samples was analyzed by Western blotting. Remaining bacteria were quantified from SEM images of the implant surfaces and their numbers statistically compared. The L-PRF-treated samples without rinsing displayed numerous cells with multiple pseudopodia in immediate contact with bacteria that appeared perforated and increased in size. The cells were identified as platelets based on morphological criteria and by positive reaction for platelet factor-4 by Western blotting. After post-treatment rinsing, the L-PRF-treated disks displayed a significant reduction in bacterial counts (in average 92% reduction). Application of L-PRF significantly reduced bacterial counts on contaminated SLA titanium surface, most likely through anti-microbial action by platelets.

Investigating alternative materials to EPDM for automatic taps in the context of Pseudomonas aeruginosa and biofilm control

Automatic taps use solenoid valves (SVs) which incorporate a rubber (typically EPDM) diaphragm to control water flow. Contaminated SVs can be reservoirs of opportunistic pathogens such as Pseudomonas aeruginosa; an important cause of healthcare-associated infection. To investigate the attachment and biofilm formation of P.aeruginosa on EPDM and relevant alternative rubbers to assess the impact on water hygiene in a laboratory model. Biofilm formation on EPDM, silicone and nitrile rubber coupons was investigated using a CDC biofilm reactor. SVs incorporating EPDM or nitrile rubber diaphragms were installed on to an experimental water distribution system (EWDS) and inoculated with P.aeruginosa. P.aeruginosa water levels were monitored for 12-weeks. SVs incorporating diaphragms (EPDM, silicone or silver ion-impregnated silicone rubber), pre-colonized with P.aeruginosa, were installed and the effect of flushing as a control measure was investigated. The concentration of P.aeruginosa in the water was assessed by culture and biofilm assessed by culture and microscopy. Bacterial attachment was significantly higher on nitrile (6.2×105 cfu/coupon) and silicone (5.4×105 cfu/coupon) rubber than on EPDM (2.9×105 cfu/coupon) (P<0.05, N=17). Results obtained invitro did not translate to the EWDS where, after 12-weeks in situ, there was no significant difference in P.aeruginosa water levels or biofilm levels. Flushing caused a superficial reduction in bacterial counts after <5min of stagnation. This study did not provide evidence to support replacement of EPDM with (currently available) alternative rubbers and indicated the first sample of water dispensed from a tap should be avoided for use in healthcare settings.

Effect of Flavonoid-Coated Gold Nanoparticles on Bacterial Colonization in Mice Organs.

Multidrug resistance (MDR) has been a potentiator for the exploration of antibiotics. Nano drug delivery systems have opened new avenues to overcome this challenge. Although antibacterial nanocarriers are extensively realized, their effect on the bacteria residing inside the tissues and their toxicity is rarely explored. This study investigated the effects of flavonoid coated gold nanoparticles (FAuNPs) on the colonization of Enterococcus faecalis in the mouse liver and kidneys. Flavonoids were extracted from the leaves of Berberis lycium Royle and used to stabilize gold following a green synthesis approach. FAuNPs were characterized by ultraviolet-visible (UV-Vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning transmission electron microscopy (STEM), X-ray powder diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). FAuNPs showed significantly higher reduction in bacterial counts in in-vitro and in-vivo in mice organs as compared to the free flavonoids owing to their biocompatibility and effectiveness.

Effects of grape and pomegranate waste extracts on poultry carcasses microbial, chemical, and sensory attributes in slaughterhouse.

Contamination of poultry carcasses is considered as a critical point in the evaluation of poultry meat safety. The present study aimed at determining the decontamination effects of natural antimicrobial derived from grape waste extract and pomegranate waste extract (GWE and PWE) on poultry carcasses in a slaughterhouse. Poultry carcasses were treated in chiller with concentrations of 0, 2, 4 and 6% of pomegranate and grape waste extracts. Pomegranate and grape waste extracts contained 432.20 and 328.43 mg GAE/g total phenolic compounds. These extracts showed significant antimicrobial effect on the main poultry bacteria in vitro. On the first day of cold storage, significant reduction in total bacterial counts (p < .05) was observed in treated carcasses. After 3 days of storage time, total bacteria, Staphylococcus aureus, and Escherichia coli reduced significantly (p < .05) compared to untreated samples. At sixth and ninth days of storage time, significant reduction in total volatile nitrogen (TVN), total bacteria counts, Staphylococcus aureus, coliforms, and Escherichia coli were observed. Sensory attributes in treated carcasses with PWE and GWE have been enhanced significantly compared to untreated during acceptable shelf time (p < .05). Based on the results, pomegranate and grape waste extracts can be used to preserve and improve the shelf life of the poultry carcasses close to the standard range until the ninth day of storage. Application of pomegranate and grape waste extracts in slaughterhouse could be considered as an environmentally, natural and safe decontamination intervention in integral food safety system.

Efficiency of some organic acids as decontaminants in sheep carcasses

Abstract Potent and food-safe antibacterial chemicals capable of decontaminating carcass surfaces have been researched for a long time due to their great value for the quality and shelf life of the meat. The aim of current study is to test the antibacterial effect of lactic acid (LA) and acetic acid (AA) spray treatments using three concentrations (1, 1.5 and 2 %) on the aerobic plate count, Enterobacteriacae count, coliform count, and Staphylococcus count of fresh sheep carcasses surface after 20 minutes of spraying. Results of the investigated bacteriological parameters showed significant reductions after being exposed to organic acids, especially Gram negative bacteria (Enterobacteriacae) which showed greater sensitivity to the used organic acids than Gram positive bacteria (Staphylococcus), where greater concentration gave greater reduction in the bacterial counts. Moreover, spray wash of lactic acid resulted in higher reduction of bacterial counts on meat surface than acetic acid. From the obtained results, organic acids showed safe, simple, efficient, cheap, and highly effective modality of meat decontamination, on addition, application of lactic acid 2.0% spray showed higher anti-bacterial effect, therefore, it is recommended to improve safety of sheep carcasses for industrial scales.

Short-Chain Fatty Acids Promote Mycobacterium avium subsp. hominissuis Growth in Nutrient-Limited Environments and Influence Susceptibility to Antibiotics.

Mycobacterium avium subsp. hominissuis (MAH) is a common intracellular pathogen that infects immunocompromised individuals and patients with pre-existing chronic lung diseases, such as cystic fibrosis, who develop chronic and persistent pulmonary infections. The metabolic remodeling of MAH in response to host environmental stresses or within biofilms formed in bronchial airways plays an important role in development of the persistence phenotype contributing to the pathogen’s tolerance to antibiotic treatment. Recent studies suggest a direct relationship between bacterial metabolic state and antimicrobial susceptibility, and improved antibiotic efficacy has been associated with the enhanced metabolism in bacteria. In the current study, we tested approximately 200 exogenous carbon source-dependent metabolites and identified short-chain fatty acid (SCFA) substrates (propionic, butyric and caproic acids) that MAH can utilize in different physiological states. Selected SCFA enhanced MAH metabolic activity in planktonic and sessile states as well as in the static and established biofilms during nutrient-limited condition. The increased bacterial growth was observed in all conditions except in established biofilms. We also evaluated the influence of SCFA on MAH susceptibility to clinically used antibiotics in established biofilms and during infection of macrophages and found significant reduction in viable bacterial counts in vitro and in cultured macrophages, suggesting improved antibiotic effectiveness against persistent forms of MAH.

Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-I concentrations, as well as the colostrum proteome

The objective of this study was to investigate the effects of heat treatment on colostral low-abundant proteins, IgG and IgA, insulin, and insulin-like growth factor I (IGF-I), as well as bacteria and somatic cells. First-milking colostrum samples >8 L and Brix % > 22.0 were harvested from 11 Holstein cows on a commercial dairy in New York State and split into 2 aliquots using single-use colostrum bags. One aliquot of each pair was cooled on ice immediately after harvest (raw, R; n = 11), and the other was heat-treated for 60 min at 60°C (heat, H; n = 11). All samples were analyzed for IgG and IgA via radial immunodiffusion assay and insulin and IGF-I concentrations by radioimmunoassay. Total bacterial counts and somatic cell counts (SCC) were determined using standard plate culture techniques and flow cytometry, respectively. Samples from a subset of 5 pairs (n = 10) were further analyzed by nano liquid chromatography-tandem mass spectroscopy, after ultracentrifugation at 100,000 × g for 60 min at 4°C to enrich the low-abundant protein whey fraction. Data were analyzed using either paired t-test or Wilcoxon signed-rank test or using an online software package to analyze proteomics data. Outcomes of proteomics analysis were fold change ≥1.5 between pairs, and paired t-tests with false discovery rate-adjusted P-value < 0.05. The median reduction of IgA concentrations was 8.5% (range: 0-38.0%) due to heat treatment, whereas IgG concentrations did not change due to treatment. Insulin concentrations decreased by a median of 22% (7-45%), and IGF-I decreased by 10% (0-18%) in H samples. Heat treatment was associated with a median reduction of SCC of 36% (0-90%) in paired samples, as well as a median reduction in total bacterial count of 93% (45-100%) in H versus R samples. Proteomics analysis identified a total of 328 unique proteins that were present in all 10 samples. Nine of the 25 proteins that decreased by at least 1.5-fold in H compared with R were identified as complement proteins. We conclude that heat treatment of colostrum is associated with a reduction in the concentration of bacterial counts and SCC, IgA, insulin, and IGF-I. In addition, proteomics analysis of colostral whey identified several complement components and other proteins that decreased in abundance due to heat treatment. Although IgG concentrations were unaffected and a reduction in bacterial counts was achieved, the change in several immunologically active proteins and growth factors may have biologically important effects on the developing immune system of the neonate fed heat-treated colostrum.

Effect of production process and high-pressure processing on viability of &lt;em&gt;Salmonella&lt;/em&gt; spp. in traditional Italian dry-cured coppa

The aim of the study was to investigate the combined effect of the manufacturing process followed by HPP treatment on the inactivation of Salmonella spp. in artificially contaminated coppa samples, in order to verify the ability of the combined processes to achieve the objective of a 5-log reduction of Salmonella spp. needed for exportation to the U.S. Fresh anatomical cuts intended for coppa production were supplied by four different delicatessen factories located in Northern Italy. Raw meat underwent experimental contamination with Salmonella spp. using a mixture of 3 strains. Surface contamination of the fresh anatomical cuts was carried out by immersion into inoculum containing Salmonella spp. The conditions of the HPP treatment were: pressure 593 MPa, time 290 seconds, water treatment temperature 14°C. Surface and deep samples were performed post contamination (T0), end of the cold phase (T1), end of process (Tend), and after HPP treatment (postHPP) and Salmonella spp. Enumerated. The results of this study show a significant reduction of Salmonella spp. all through the production process (P<0.01) for all companies, followed by an additional reduction of bacterial counts due to HPP treatment (P<0.01), both in superficial and deep contaminations (P<0.01). The superficial overall reduction resulted of 1.58 to 5.04 log CFU/g during the production process. HPP treatment resulted in a significant (P<0.01) superficial and deep decrease in Salmonella spp. enumeration varying from 0.61 to 4.01 log and from 1.49 to 4.13 log. According to the data presented in this study, only the combined approach of coppa manufacturing process followed by HPP treatment always led to a 5-log reduction of Salmonella spp. required by USDA/FSIS guidelines.

Characterization, Antibiofilm, and Depolymerizing Activity of Two Phages Active on Carbapenem-Resistant Acinetobacter baumannii.

Acinetobacter baumannii is a leading cause of healthcare-associated infections worldwide. Its various intrinsic and acquired mechanisms of antibiotic resistance make the therapeutic challenge even more serious. One of the promising alternative treatments that is increasingly highlighted is phage therapy, the therapeutic use of bacteriophages to treat bacterial infections. Two phages active against nosocomial carbapenem-resistant A. baumannii strain 6077/12, vB_AbaM_ISTD, and vB_AbaM_NOVI, were isolated from Belgrade wastewaters, purified, and concentrated using CsCl gradient ultracentrifugation. The phages were screened against 103 clinical isolates of A. baumannii from a laboratory collection and characterized based on plaque and virion morphology, host range, adsorption rate, and one-step growth curve. Given that phage ISTD showed a broader host range, better adsorption rate, shorter latent period, and larger burst size, its ability to lyse planktonic and biofilm-embedded cells was tested in detail. Phage ISTD yielded a 3.5- and 2-log reduction in planktonic and biofilm-associated viable bacterial cell count, respectively, but the effect was time-dependent. Both phages produced growing turbid halos around plaques indicating the synthesis of depolymerases, enzymes capable of degrading bacterial exopolysaccharides. Halos tested positive for presence of phages in the proximity of the plaque, but not further from the plaque, which indicates that the observed halo enlargement is a consequence of enzyme diffusion through the agar, independently of the phages. This notion was also supported by the growing halos induced by phage preparations applied on pregrown bacterial lawns, indicating that depolymerizing effect was achieved also on non-dividing sensitive cells. Overall, good rates of growth, fast adsorption rate, broad host range, and high depolymerizing activity, as well as antibacterial effectiveness against planktonic and biofilm-associated bacteria, make these phages good candidates for potential application in combating A. baumannii infections.

The effect of oil pulling with coconut oil to improve dental hygiene and oral health: A systematic review

ObjectivesCoconut oil is a cheap and accessible oil for many people around the world. There are numerous advocates for the practice of oil pulling to prevent common oral diseases. Therefore determining the effectiveness of oil pulling with coconut oil could potentially have monumental benefits. This review aimed to assess the effect of oil pulling with coconut oil in improving oral health and dental hygiene. DataWe included randomized controlled trials comparing the effect of oil pulling with coconut oil on improving oral health and dental hygiene.No meta-analysis was performed due to the clinical heterogeneity and differences in the reporting of data among the included studies. SourcesSix electronic databases were screened: PubMed, Medline, EMBASE, AMED, CENTRAL and CINAHL. Study selectionElectronic searches yielded 42 eligible studies, of which four RCTs including 182 participants were included. The studies lasted between 7 and 14 days. Significant differences were demonstrated for a reduction in salivary bacterial colony count (p = 0.03) and plaque index score (p=<0.001). One study also demonstrated a significant difference in staining compared to using Chlorhexidine (p = 0.0002). However, data was insufficient for conclusive findings, the quality of studies was mixed and risk of bias was high. ConclusionThe limited evidence suggests that oil pulling with coconut oil may have a beneficial effect on improving oral health and dental hygiene. Future clinical trials are of merit considering the universal availability of the intervention. Prospective research should have a robust design with rigorous execution to provide a higher quality of evidence. Clinical significanceOil pulling with coconut oil could be used as a adjunct to normal preventative regimes to improve oral health and dental hygiene although further studies are needed to determine the level of effectiveness.

Clinical efficacy of a probiotic fluoride dentifrice: A comparitive clinical and microbiologic study

Introduction: Oral cavity harbors wide variety of microorganisms; these are considered crucial for the dental caries initiation and progression. Plaque-induced caries is a local disease; therefore, dentifrices are the most ideal vehicle for the daily delivery of antibacterial agents. In recent years, adjuncts to fluorides such as probiotics chlorhexidine have been proposed to in view of antiplaque and anticariogenic properties by means of reduction of bacterial count. Aim: The study aimed to evaluate the anticariogenic activity and improvement in the oral health status of participants over a period of 45 days. Materials and Methods: A single blinded, parallel group, randomized controlled clinical study was conducted among healthy adults. Thirty individuals were randomly allocated to two groups (n = 15): Group I – probiotic dentifrice (test group) Group II – no intervention (control group) Saliva samples were evaluated for Streptococcus mutans colony forming unit (CFU/ml of saliva) at baseline, 15th, 30th, 45th day of follow-up. Paired t-test and one-way. ANOVA were used to compare the mean differences of salivary S. mutans counts at the three time periods. Results: The mean S. mutans counts in saliva samples were significantly reduced in the treatment group at the 45th day of follow-up. Conclusion: The test group exhibited antimicrobial activity by bringing about a significant reduction in the mean S. mutans colony counts at the 30th day & 45th day of follow-up. Keywords: Probiotic, Streptococcus mutans, Dentifrice.

Antissepsia cirúrgica das mãos com preparação alcoólica: redução microbiana em diferentes tempos de uso no centro cirúrgico

Objetivo: Avaliar a redução microbiana após antissepsia cirúrgica das mãos dos cirurgiões, realizada com preparação alcoólica, em diferentestempos. Método: Estudo de prevalência, pragmático, de campo, realizado em hospital terciário do Brasil. Coletaram-se amostras microbiológicas dasmãos de 54 cirurgiões após lavagem simples, para determinar a flora microbiana basal e, após a antissepsia cirúrgica alcoólica, para avaliar a reduçãomicrobiana imediata. Categorizaram-se os resultados da redução microbiana em redução leve (até 50% de redução da flora bacteriana), moderada (de51 a 80%) e alta (acima de 80%). A pesquisa foi submetida e aprovada pelo Comitê de Ética e Pesquisa da instituição hospitalar privada, sede do estudo, eda instituição de ensino superior federal. Resultados: Nas técnicas realizadas em menos de 90 segundos, houve 80% de redução severa, 6,7% de reduçãomoderada e 13,3% de redução leve. Nas técnicas desempenhadas em mais de 180 segundos, todas as amostras apresentaram redução de contagem bacteriana,o que não ocorreu em tempos menores de antissepsia. Conclusão: Quando a técnica e o tempo recomendados são seguidos, maior é a reduçãobacteriana, em comparação aos tempos menores.

The Effect of Antimicrobial Photodynamic Therapy Using Chlorophyllin–Phycocyanin Mixture on Enterococcus faecalis: The Influence of Different Light Sources

The purpose of this study was to evaluate the in vitro effect of the chlorophyllin–phycocyanin mixture (Photoactive+) as a photosensitizer (PS) during antimicrobial photodynamic therapy (aPDT) on the count of Enterococcus faecalis (E. faecalis) using different light sources. The antimicrobial effect of aPDT with chlorophyllin–phycocyanin mixture using different light sources including diode laser (λ = 660 nm), diode laser (λ = 635 nm), LED (λ = 450 ± 30 nm) alone or in combination was assessed using microbial cell viability assay against E. faecalis. In addition, the cell cytotoxicity of Photoactive+ was assessed on human gingival fibroblast (HuGu) cells by MTT assay; E. faecalis growth when treated by both red wavelengths (635 nm, 660 nm) and combination of LED (420–480 nm) and red wavelengths (635 nm, 660 nm), significantly reduced compared to the control group (p &lt; 0.05). There was no significant reduction in the number of viable cells exposed to Photoactive+ compared to the control group (p &lt; 0.05). This study shows that the application of chlorophyllin–phycocyanin mixture and irradiation with emission of red light achieved a better result for bacterial count reduction, compared to a control. This component can be applied safely due to very negligible cytotoxicity.

Immunomodulatory dose of clindamycin in combination with ceftriaxone improves survival and prevents organ damage in murine polymicrobial sepsis.

Sepsis is a life-threatening organ dysfunction resulting from inflammatory responses instigated by toxins secreted by bacteria. Immunomodulatory effect of clindamycin is earlier reported in a murine lipopolysaccharide (LPS)-induced sepsis model. There are no studies demonstrating the immunomodulatory effect of clindamycin in combination with ceftriaxone in a clinically relevant murine polymicrobial sepsis model induced by cecal ligation and puncture (CLP). Ceftriaxone is combined to control the bacterial growth. Following 3h of CLP challenge, Swiss albino mice were administered vehicle, ceftriaxone alone (100mg/kg, subcutaneously), and in combination with clindamycin at immunomodulatory dose (200mg/kg, intraperitoneally). Survival was assessed for 5days, and bacterial count and biochemical and physiological parameters were measured after 18h of CLP challenge. Ceftriaxone alone caused significant reduction in bacterial count in blood, peritoneal fluid, lung, liver, and kidney homogenate which was not further substantially reduced by ceftriaxone and clindamycin combination. Day 5 survival was greatly improved by combination compared with ceftriaxone alone which was also evident through marked drop in blood glucose, total white blood cell (WBC) count, and body temperature. The combination group significantly mitigated the cytokine (tumor necrosis factor (TNF)-α and interleukin (IL)-6) and myeloperoxidase (MPO) levels in plasma, lung, liver, and kidney of CLP-challenged mice, which further helped in significantly suppressing the elevated levels of liver and kidney function parameters. Clindamycin at immunomodulatory dose in combination with ceftriaxone attenuated organ damage and improved survival of septic mice by suppressing infection, inflammatory responses, and oxidative stress.

Dual-light photodynamic therapy administered daily provides a sustained antibacterial effect on biofilm and prevents Streptococcus mutans adaptation.

Antibacterial photodynamic therapy (aPDT) and antibacterial blue light (aBL) are emerging treatment methods auxiliary to mechanical debridement for periodontitis. APDT provided with near-infrared (NIR) light in conjunction with an indocyanine green (ICG) photosensitizer has shown efficacy in several dental in-office-treatment protocols. In this study, we tested Streptococcus mutans biofilm sensitivity to either aPDT, aBL or their combination dual-light aPDT (simultaneous aPDT and aBL) exposure. Biofilm was cultured by pipetting diluted Streptococcus mutans suspension with growth medium on the bottom of well plates. Either aPDT (810 nm) or aBL (405 nm) or a dual-light aPDT (simultaneous 810 nm aPDT and 405 nm aBL) was applied with an ICG photosensitizer in cases of aPDT or dual-light, while keeping the total given radiant exposure constant at 100 J/cm2. Single-dose light exposures were given after one-day or four-day biofilm incubations. Also, a model of daily treatment was provided by repeating the same light dose daily on four-day and fourteen-day biofilm incubations. Finally, the antibacterial action of the dual-light aPDT with different energy ratios of 810 nm and 405 nm of light were examined on the single-day and four-day biofilm protocols. At the end of each experiment the bacterial viability was assessed by colony-forming unit method. Separate samples were prepared for confocal 3D biofilm imaging. On a one-day biofilm, the dual-light aPDT was significantly more efficient than aBL or aPDT, although all modalities were bactericidal. On a four-day biofilm, a single exposure of aPDT or dual-light aPDT was more efficient than aBL, resulting in a four logarithmic scale reduction in bacterial counts. Surprisingly, when the same amount of aPDT was repeated daily on a four-day or a fourteen-day biofilm, bacterial viability improved significantly. A similar improvement in bacterial viability was observed after repetitive aBL application. This viability improvement was eliminated when dual-light aPDT was applied. By changing the 405 nm to 810 nm radiant exposure ratio in dual-light aPDT, the increase in aBL improved the antibacterial action when the biofilm was older. In conclusion, when aPDT is administered repeatedly to S. mutans biofilm, a single wavelength-based aBL or aPDT leads to a significant biofilm adaptation and increased S. mutans viability. The combined use of aBL light in synchrony with aPDT arrests the adaptation and provides significantly improved and sustained antibacterial efficacy.