Increasing community prevalence of extended-spectrum beta-lactamase-producing Escherichia coli in urine is associated with increasing district-level antibiotic consumption.

INTRODUCTION: This study aimed to analyze ESBL-producing Escherichia coli prevalence in urine samples collected between 2011-2019 in Curitiba, a large city in Brazil, and relating it to antibiotic consumption and sanitary conditions. METHODS: This is a longitudinal study correlating prevalence of ESBL-producing E. coli isolates from urine samples with district-level antibiotic consumption and sociodemographic data during 2011-2019. E. coli isolates were tested for antibiotic susceptibility and ESBL by an automated method. Statistical analysis applied linear regressions, pooled ordinary least squares, and fixed effects models for districts or years. The Chow and Hausman tests indicated that the fixed effects model for individual districts fitted best. Chi-square test was used for qualitative variables (statistical significance was set when p<0.05). RESULTS: Among the 886,535 urine sample cultures, 9.9% of isolates were ESBL-producing E. coli. Their prevalence increased from 4.7% in 2011 to 19.3% in 2019 (p<0.0001; R2=0.922). This progressive increase correlated with age (p=0.007; R2=0.8725) and male gender (p<0.001) and increased antibiotic consumption (p=0.0386; R2=0.47). The fixed effects model showed that district influences ESBL prevalence and that antibiotic consumption explains 20-30% of this variation, with an increase of one defined daily dose accounting for an increase of 0.02084 percentage points of ESBL. CONCLUSIONS: The increasing prevalence of ESBL-producing E. coli can, to a considerable extent, be explained by increasing antibiotic consumption.

Demographic, socioeconomic, and health structure factors associated with the use of HIV pre-exposure prophylaxis in Brazil: A nationwide ecological study.

Aims: To assess the cumulative rate of HIV Pre-Exposure Prophylaxis (PrEP) users in Brazil since its 2018 implementation and to analyze the association between PrEP usage and state-level structural factors. Methods: A nationwide ecological study from 2018 to 2022 was conducted, examining the 5-year cumulative rate of PrEP users in relation to demographic, socioeconomic, and healthcare infrastructure variables. Multiple linear regression analysis identified significant predictors of PrEP utilization. Results: Between 2018 and 2022, 124,796 individuals used PrEP, with a cumulative rate of 61.5 per 100,000 population. The highest usage was in Minas Gerais, São Paulo, and Santa Catarina, while the lowest was in Distrito Federal, Maranhão, and Alagoas. Regression analysis showed that higher PrEP usage was associated with lower population density, a younger median age, a lower male to female ratio, and reduced social vulnerability. Additionally, PrEP usage was positively associated with the density of medical doctors and the number of dispensing units. Conclusions: The study reveals significant regional disparities in PrEP usage across Brazil, influenced by socioeconomic and healthcare factors. It highlights the need for targeted public health strategies to enhance PrEP access and uptake, especially in socially vulnerable regions.

Plasma Jet versus Electrocarbonization in the Treatment of Wrinkles of the Upper Palpebral Region.

Background: The plasma jet is a non-surgical and minimally invasive procedure that acts by heating the superficial region of the skin, providing rejuvenation of the region. Objective: We sought to compare the clinical and histological effects of direct plasma jet versus electrocarbonization without plasma in the treatment of wrinkles in the upper palpebral region. Methods: This is a clinical trial in which 20 volunteers participated and divided into two groups: electrocarbonization (EG) and plasma jet (JPG), which were clinically evaluated before and after treatment through evaluation protocols, photographs, and questionnaires. Three treatment sessions were performed in the upper eyelid region with an interval of 30 days. After the treatment, a surgical procedure of upper blepharoplasty was performed on two volunteers to remove a skin fragment and later histological analysis. Results: The JPG showed better clinical responses in rejuvenation. The EG promoted an increase in the number of fibroblasts, the number of blood vessels and the amount of inflammation. The JPG showed an increase in the number of fibroblasts and blood vessels. It was observed that the JPG generated activation of T lymphocytes (CD3), macrophages (CD68), and plasmocytes (CD138); in addition to reducing the number of positive cells for CD57 (NK cells). The satisfaction analysis shows that 100 percent in the JPG considered themselves satisfied with the treatment. Conclusion: We verified that in comparison with electrocarbonization, the use of a direct plasma jet promoted tissue improvement at the histological level, in addition to fewer adverse reactions.

Scoping review: Effect of surface treatments on bond strength of resin composite repair.

OBJECTIVE: to evaluate the existing evidence on surface treatment techniques employed in resin composite repair and their effect on the repair short- and long-term bond strength. DATA AND SOURCE: This scoping review was performed under the PRISMA-ScR guidelines for scoping reviews and registered on the Open Science Framework platform. STUDY SELECTION: A systematic search was conducted in PubMed, Embase, and Scopus and grey literature up to September 2022 without language or date restriction. In vitro studies comparing mechanical surface and/or chemical treatments on repair bond strength of resin composite were included. Studies evaluating experimental adhesive systems or resin composites were excluded. Selection of studies and data extraction were performed. Data from selected studies was qualitatively analyzed. RESULTS: A total of 76 studies were included in the qualitative analysis. Among the mechanical treatments, alumina blasting was the most frequently used, followed by silica coating and diamond bur. As for chemical treatments, dentin bonding systems were the most frequently evaluated, followed by universal adhesive systems and silane/ceramic primer. The combination of mechanical and chemical pre-treatments increased the repair bond strength of resin composite in both short- and long-term simulated aging scenarios. The evidence obtained from the included studies was classified as moderate quality, mainly due to the medium risk of bias observed across most of the studies. CONCLUSION: The techniques used to treat the surface of resin composites for repair are diverse. Incorporating a combination of mechanical and chemical pre-treatments resulted in superior repair bond strength of resin composite materials under both short- and long-term simulated aging conditions. CLINICAL SIGNIFICANCE: The analysis of evidence revealed significant variability among protocols for repairing resin composites. Utilizing both mechanical and chemical pre-treatment methods is important for enhancing the bond strength of resin composites during both short- and long-term simulated aging situations.

Peeling with retinoic acid in microemulsion for treatment of melasma: A double-blind randomized controlled clinical study.

OBJECTIVE: To evaluate the clinical efficacy of peeling with a microemulsion formulation containing 1% retinoic acid. MATERIALS AND METHODS: After development of the product, 60 patients with melasma were randomly divided into three groups (n = 20): Group 1-application of conventional 1% retinoic acid peeling (RA 1%). Group 2-application of 1% retinoic acid peeling in microemulsion (RA 1%M). Group 3-Application of placebo. The groups were submitted to four peeling sessions, fortnightly on Days 0, 15, 30, and 45, and analyzed at the time intervals of 0, 15, 30, 45, and 60 days. Evaluation was made by using the Melasma Area and Severity Index (MASI) and Melasma Quality of Life (MelasquoL) instrument. Hemato-biochemical parameters were also evaluated at Days 0 and 60. After obtaining the results, normality was evaluated by means of the Kolmogorov-Smirnov test and afterwards, the following tests were applied: Friedman statistical (to test the effect of the treatments on the MASI index); Wilcoxon, (for comparison between pairs to test the effect of treatments on the MelasQoL index); Kruskal-Wallis, (to test the differences between the groups); and Mann-Whitney, (comparisons between treatments). The level of significance adopted was 5% (α = 0.05). RESULTS: The three groups presented a significant reduction in the MASI index, indicating the effect of all the treatments on reducing the melasma (p < 0.001). A significant reduction in the stains was observed with the use of retinoic acid peeling delivered in microemulsion (62%) when compared with the conventional peeling with 1% retinoic acid in a conventional vehicle (26%) and the placebo (12%). There was also a significant reduction in the MelasQoL index (sum of all the aspects) in the three groups, indicating the effect of all the treatments, including the placebo, on the overall quality of life of those with melasma. However, RA 1%M the treatment that promoted the greatest effect on the quality of life of individuals. In percentage terms, the RA 1%M provided a mean reduction of 30% in the MelasQoL index, against 13% of the conventional treatment and only 4% of the placebo. When the hemato-biochemical parameters were compared on Days 0 and 60, there were no significant changes in the results. CONCLUSION: The chemical peeling performed with RA 1%M was effective for the treatment of melasma, and was shown to be superior to the peeling performed with retinoic acid in a conventional vehicle, in reducing the stains and improving the quality of life of patients.

Innovation of the protocol for the application of cryolipolysis: Effects and mechanisms of action.

BACKGROUND: In recent years, aesthetic procedures aiming at body remodeling and have grown exponentially. Cryolipolysis (CLL) has stood out as a noninvasive resource that acts directly on the subcutaneous adipose tissue promoting a significant reduction of adipose tissue through of cooling that could lead to the crystallization cytoplasmic lipids, loss of cellular integrity, apoptosis/necrosis of adipocytes, and local inflammation, producing selective loss of adipose tissue. Thus, the objective of the present study was to evaluate the effects of a specific technique of CLL application on the inflammatory reactions of the target tissue in different post-application times. METHODS: This is a randomized, blind clinical study that evaluated the tissue sample of six patients after 45, 60, and 90 days of an innovative protocol for the application of CLL, with samples collected through abdominoplasty surgeries. The samples were evaluated by immunohistochemical analyses of several markers. RESULTS: A significantly greater increase in fibroblasts was observed at 45 days and greater phagocytic action at 60 days. Regarding the apoptosis process, the expression of caspase 3 and cleaved caspase 3 markers varied at different times, with cleaved caspase 3 being higher at 45 and 90 days after CLL application. CONCLUSION: The protocol of the CLL presented in this study was able to induce inflammatory responses in addition to confirming the selective apoptotic action at the different times studied.

Evaluation of silver nanoparticle-impregnated PMMA loaded with vancomycin or gentamicin against bacterial biofilm formation.

INTRODUCTION: Bone cement containing vancomycin or gentamicin is a therapeutic strategy for combating orthopedic infections: however, the activity of these antibiotics is narrow. Silver nanoparticles (AgNPs) are nanocomponents with a wide spectrum, including multidrug-resistant bacteria. In the present study, we aimed to evaluate the effect of AgNP-loaded polymethylmethacrylate (PMMA) on biofilm formation by Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus epidermidis. METHODS: The effect of AgNP-loaded PMMA with and without vancomycin or gentamicin on biofilm production was quantitatively analyzed. S. aureus, E. coli, P. aeruginosa, and S. epidermidis were included as biofilm-producing microorganisms in the in vitro model. RESULTS: AgNP-loaded PMMA with antibiotics reduced the number of colony-forming units (CFUs; p<0.001). However, AgNP-loaded PMMA alone did not significantly reduce biofilm formation. CONCLUSION: Our study demonstrated the potential of AgNP-loaded PMMA. Notably, we observed that AgNP-loaded PMMA containing vancomycin or gentamycin exhibited significantly superior efficacy, with satisfactory activity against most biofilm-forming microbial agents examined.

Edge effects on tree architecture exacerbate biomass loss of fragmented Amazonian forests.

Habitat fragmentation could potentially affect tree architecture and allometry. Here, we use ground surveys of terrestrial LiDAR in Central Amazonia to explore the influence of forest edge effects on tree architecture and allometry, as well as forest biomass, 40 years after fragmentation. We find that young trees colonising the forest fragments have thicker branches and architectural traits that optimise for light capture, which result in 50% more woody volume than their counterparts of similar stem size and height in the forest interior. However, we observe a disproportionately lower height in some large trees, leading to a 30% decline in their woody volume. Despite the substantial wood production of colonising trees, the lower height of some large trees has resulted in a net loss of 6.0 Mg ha-1 of aboveground biomass - representing 2.3% of the aboveground biomass of edge forests. Our findings indicate a strong influence of edge effects on tree architecture and allometry, and uncover an overlooked factor that likely exacerbates carbon losses in fragmented forests.

Effect of photobiomodulation on the behaviour of mesenchymal stem cells in three-dimensional cultures.

Photobiomodulation (PBM) has been proposed as a strategy to improve the regenerative capacity of human adipose-derived stem cells (hASCs). Yet, this effect has been proved in 2D culture conditions. To analyze the effect of different doses of laser irradiation (660 nm) with different levels of energy (1 J, 2 J and 6 J) on hASCs cultured at 2D and 3D conditions. We used gellan gum spongy-like hydrogels as a biomaterial to 3D culture hASCs. Different doses (1-7 daily irradiations) and energy levels (1-6 J) of PBM were applied, and the metabolic activity, viability, proliferation, and release of ROS and IL-8 was evaluated up to 7 days. In 3D, cell proliferation increased at high energy (6 J) and after a single dose of irradiation, while in 2D, metabolic activity and proliferation was enhanced only after 3 doses and independently of the energy. More than 1 dose was needed to promote ROS secretion both in 2D and 3D culture conditions. Interestingly, a decrease of IL-8 secretion was detected only in 3D after 3-7 daily irradiations. Overall, hASCs response to PBM was not only dependent on the energy level and the number of applied stimuli, but also on the in vitro culture conditions.

Evaluation of Single-Shade Composite Resin Color Matching on Extracted Human Teeth.

Introduction: Universal single-shade composite resins are characterized by a property that enables the creation of restorations that mimic tooth structure to the extent possible with fewer shades of color. Objectives: This study aimed to instrumentally and visually evaluate the color correspondence of two single-shade composite resins in extracted human teeth multishade composite resins. Methods: Upper central incisors and upper and/or lower molars with intact buccal surfaces were selected. The study consisted of a control group (n = 20): Z250 XT (3M ESPE) (G1) multishade composite resin in colors A1 to A4, and a test group (n = 20) divided further into two equal groups, consisting of single-shade composite resin Omnichroma (Tokuyama Dental) (G2) and single-shade composite resin Vittra APS Unique from (FGM) (G3). Instrumental evaluation was performed using a spectrophotometer, and visual evaluation was performed by three observers. Descriptive measurements related to the differences in color obtained through instrumental means were analyzed using mean and standard deviation, wherein the means were compared using ANOVA, applying the Bonferroni post hoc test. Results: A statistically significant difference was observed among the groups (G1, G2, and G3) (ANOVA: p < 0.001). For the visual assessment, regardless of the assessment group, 77.49% of the teeth were within the acceptable color-match classification, with the single-shade resins showing better correspondence than the multishade resins. Conclusion: Single-shade composite resins showed different color-matching results when compared to multishade resins, both in spectrophotometry and visual evaluations. Clinical Significance. Single-shade composite resins simplify the shade-selection process and are promising materials for use in dental practice.

Oral doxycycline to carbapenem-resistant Acinetobacter baumannii infection as a polymyxin-sparing strategy: results from a retrospective cohort.

Acinetobacter baumannii infection presents a high mortality rate and few therapeutic options. This study aimed to evaluate clinical-microbiological characteristics and prognosis factors of patients diagnosed with A. baumanni. infections treated with oral doxycycline. A retrospective cohort of hospitalized patients with confirmed Acinetobacter spp. infection between 2018 and 2020 receives at least 3 days of oral doxycycline. Clinical and microbiological data were evaluated, including the outcome and molecular characterization of A. baumannii. Doxycycline minimal inhibitory concentrations were evaluated by the broth dilution method. One hundred patients were included with a median age of 51 years. The leading site of infection was pulmonary (n = 62), followed by the soft tissues and skin (n = 28). A. baumannii resistant to carbapenem was found on 94%. The gene blaOXA-23 and blaOXA-51 were amplified in all recovered isolates of A. baumannii (n = 44). Doxycycline MIC50 and MIC90 were 1 µg/mL and 2 µg/mL, respectively. Death rate at 14 days and 28 days of follow-up was 9% and 14%, respectively. The prognostic factors related to death at end of follow-up were age > 49 years [85.7% vs. 46%, CI 95% 6.9 (1.4-32.6), P = 0.015] and hemodialysis [28.6% vs. 7%, CI 95% 5.33 (1.2-22.1), P = 0.021]. Patients treated with doxycycline to A. baumannii presented a relatively low death rate, and risk factors related to death were age and hemodialysis. Further and larger studies should compare polymyxin to doxycycline to better understand the differences between these therapeutic options.

The Landscape of Neutralizing Monoclonal Antibodies (nAbs) for Treatment and Prevention of COVID-19.

Purpose: After nearly 3 years of the COVID-19 pandemic, even though a vast body of knowledge and products (including vaccines and treatments) have been developed and disseminated, the virus is still evolving and new variants arising. Consequently, thousands of lives continue to be lost. Neutralizing monoclonal antibodies (nAbs) are promising drugs that emerged to treat SARS-CoV-2. In the uncertainty of the current situation, there is the question of whether organizations should continue to invest in this technology. To help decision-making in scientifical and pharmaceutical organizations, it is of major importance to monitor the development of products and technologies. Therefore, the aim of this study is analyze the landscape of nAbs for COVID-19. Methods: The scenario of 473 biotherapeutics focusing on nAbs was evaluated using foresight techniques and a review of literature. Data were obtained from structured and semi-structured databases and processed for treatment, cleaning, consistency, validation, and enrichment. Results: We identified 227 nAbs and performed an extensive literature review of 16 nAbs in late clinical development, including development technologies, responses to variants of concern (VOCs), manufacturing, and clinical aspects. Conclusions: Even though the emergence of new VOCs is a threat to the effectiveness of this treatment, demanding constant genomic surveillance, the use of nAbs to treat and prevent COVID-19 will probably continue to be relevant due to excellent safety profiles and the possibility of immediate immunity transfer, especially in patients showing inadequate immunological response to vaccination. Therefore, we suggest that organizations should keep investing in improvements in this technology.

3D-printed PMMA implant for gingival smile treatment through the VISTA technique: A report of a new approach.

BACKGROUND: A gingival display higher than 3 mm is considered a characteristic of a gingival smile (GS). Several etiological factors have been associated to GS and for this reason various treatments have been proposed according to its etiology. The aim of this study is to present a case with an alternative technique to treat GS with minimally invasive vestibular incision subperiosteal tunnel access (VISTA) and polymethyl methacrylate (PMMA) implants for lip repositioning. METHODS AND RESULTS: The patient, a 25-year-old woman diagnosed with excessive gingival exposure, had previously done botulinum toxin (BoNT) injections and did not like the result. She had a major subnasal depression and the upper lip would lodge in there during spontaneous smile. She was informed about all options of treatment and agreed to a lip repositioning installing a customized PMMA implant. CONCLUSION: This is the first study to our knowledge to present a case with use of a PMMA implant associated with the VISTA approach for lip repositioning and gingival smile correction. The results are encouraging, and the patient was satisfied with results accomplished by this technique. KEY POINTS: Why is this case new information? This is a new and innovative surgical approach for gingival smile with PMMA implants through a minimally invasive technique (VISTA). What are the keys to successful management of this case? Well-defined presurgical planning and the presence of the upper lip lodging in the subnasal depression during spontaneous smile. What are the primary limitations to success in this case? Cases with vertical maxillary excess and those in which osteotomy/osteoplasty is indicated. It is a technique-sensitive treatment dependent on the clinician's experience.

Malassezia spp. and Candida spp. from patients with psoriasis exhibit reduced susceptibility to antifungals.

INTRODUCTION: Psoriasis is a chronic inflammatory disease that affects over 125 million people worldwide. Many studies have shown the importance of the microbiome for psoriasis exacerbation. AIM: Explore the fungal load and species composition of cultivable yeasts on the skin of psoriatic patients (PP) and healthy volunteers living in a tropical area and evaluate the susceptibility to antifungals. METHODOLOGY: A cross-sectional study with 61 participants (35 patients and 26 healthy controls) was performed during August 2018 and May 2019. Clinical data were collected from patient interviewing and/or medical records review. Samples were collected by swabbing in up to five anatomic sites. Suggestive yeast colonies were counted and further identified by phenotypical tests, PCR-REA, and/or MALDI-TOF. Susceptibility of Malassezia spp. and Candida spp. to azoles, terbinafine, and amphotericin B was evaluated by broth microdilution. RESULTS: Nearly 50% of the patients had moderate to severe psoriasis, and plaque-type psoriasis was the most common clinical form. Yeast colonies count was significantly more abundant among PP than healthy controls. Malassezia and Candida were the most abundant genus detected in all participants. Higher MIC values for ketoconazole and terbinafine were observed in Malassezia strains obtained from PP. Approximately 42% of Candida isolates from PP showed resistance to itraconazole in contrast to 12.5% of isolates from healthy controls. MIC values for fluconazole and amphotericin B were significantly different among Candida isolates from PP and healthy individuals. CONCLUSION: This study showed that Malassezia and Candida strains from PP presented higher MIC values to widespread antifungal drugs than healthy individuals.

Evaluation of the Effectiveness of Cutting Scalpel Blades After Use and leaning by Different Methods / Avaliação da Efetividade do Corte de Lâminas de Bisturi Após Uso e Limpeza Por Diferentes Métodos

When performing incisions during oral and maxillofacial surgical procedures, the surgeon requires a blade that ensures precise cuts which reduce unnecessary tissue injuries. After searching the literature, we realized that there is a lack of studies that assesses scalpel blades for dental use. Herein, this study aims to assess the cutting power of new scalpel blades after cleaning with different methods. Sixty sterile scalpel blades were divided into seven groups: I) new blade; II) the second insertion; III) blade cleaned with gauze; IV) blade cleaned with gauze and saline; V) blade cleaned with saline; VI) blade cleaned with cotton, and VII) blade cleaned with cotton and saline. A universal testing machine (Osvaldo Filizola, São Paulo, Brazil) was used for the insertion and measurement of the shear strength. The results revealed that cleaning the blade with gauze and saline was the method that had the greatest loss of the cutting capability. The reinsertion of the scalpel blade without any type of cleaning or the cleaning of the blade with cotton and saline were the methods that obtained the best result, which did not compromise the mechanical properties of the tested material. This study concludes that cleaning methods affect the cutting power of scalpel blade

Na execução dos procedimentos cirúrgicos bucais e maxilofaciais o operador, ao realizar incisões, necessita de uma lâmina que garanta um corte preciso, diminuindo lesões desnecessárias aos tecidos. Ao fazer uma busca na literatura, constatou-se carência de estudos que avaliassem lâminas de bisturi de uso odontológico. Diante desse cenário, o objetivo do presente estudo foi avaliar o poder de corte de lâminas de bisturi novas e após limpeza com diferentes métodos. Sessenta lâminas de bisturi estéreis foram divididas em sete grupos: I) lâmina nova; II) segunda inserção; III) lâmina limpa com gaze; IV) lâmina limpa com gaze e soro; V) lâmina limpa com soro; VI) lâmina limpa com algodão e VII) lâmina limpa com algodão e soro. Para inserção e aferição da resistência ao corte utilizou-se uma máquina de ensaio universal (Osvaldo Filizola, São Paulo, Brasil). Os resultados revelaram que a limpeza da lâmina com gaze e soro fisiológico foi o método que teve maior perda de corte. Já a reinserção da lâmina de bisturi sem quaisquer tipos de limpeza ou a limpeza da lâmina com algodão e soro foram as que obtiveram melhor resultado, não comprometendo as propriedades mecânicas do material testado. Conclui-se, com a realização desse estudo, que os métodos de limpeza afetam o poder de corte das lâminas de bisturi.

Dimethoate absorption: A complementary in vitro and in vivo assessment.

This work attempts to evaluate dermal exposure (DE) of farm workers to dimethoate after 4 h of routine application to a lemon plantation. Dimethoate was measured on the workers' clothes as well as in stratum corneum (SC) and in saliva. In vitro permeation tests (IVPT) were performed through rat, pig and human skin and pig buccal, esophageal and sublingual mucosas. The mean of dimethoate DE was 342.19 ± 487.14 mg/d, the percentage of toxic dose per hour was higher than the other pesticides, and the SC penetration factors ranged between 0.5 and 14.81 and 0.05-53.96 % for back of neck and arms respectively. In the supporting IVPT study, dimethoate absorption through human skin was 14.75 % and the default value in the absence of experimental data for this product is 70%. These results show that in family farming the deficiency of correct clothing during the application of pesticides leaves workers more vulnerable.

A carbapenem-resistant Acinetobacter baumannii outbreak associated with a polymyxin shortage during the COVID pandemic: an in vitro and biofilm analysis of synergy between meropenem, gentamicin and sulbactam.

BACKGROUND: During the COVID-19 pandemic, the burden of nosocomial infections caused by MDR pathogens has caused a shortage of polymyxins. Thus, we evaluated the in vitro synergism and antibiofilm activity of antimicrobial combinations and propose a test kit for synergism against carbapenem-resistant Acinetobacter baumannii (CRAB). METHODS: Fifty-six CRAB isolates were tested for synergy between meropenem, gentamicin and ampicillin/sulbactam. MICs were determined by broth microdilution. Synergism was tested using chequerboard analysis, followed by a time-kill curve. Additionally, minimum biofilm eradication concentration was determined and the antibiofilm activity of the combinations was evaluated by MTT assay and biomass reduction. A test kit was developed for routine laboratory testing to detect synergism. RESULTS: All CRAB isolates were resistant to gentamicin and ampicillin/sulbactam. Chequerboard synergism occurred against 75% of the isolates. Meropenem + ampicillin/sulbactam was the most frequent combination with synergism (69%), followed by ampicillin/sulbactam + gentamicin (64%) and meropenem + gentamicin (51%). All combinations presented only bacteriostatic activity and no bactericidal or antibiofilm effects. The routine laboratory test showed 100% accuracy compared with other in vitro assays. CONCLUSIONS: Our study demonstrates the potential role of antibiotic combinations against planktonic bacteria. In vitro synergism is possible and can be an alternative treatment for patients with CRAB infection during a polymyxin shortage.

Release of Matrix Metalloproteinases by Macrophages in Radicular Cysts and Residual Radicular Cysts.

INTRODUCTION: Radicular cysts (RCs) and residual radicular cysts (RRCs) are the sequelae of dental caries and that leads to proliferation of epithelial rests of Malassez in periapical tissues. OBJECTIVES: The aim was to evaluate the relationship between Langerhans cells, macrophages, matrix metalloproteinases (MMP-9, MMP-13), and tumor necrosis factor-alpha (TNF-α) in the capsule and lining epithelium of cystic lesions. MATERIALS AND METHODS: Twenty RCs and 20 RRCs were submitted to immunohistochemical analysis with anti-CD68, anti-CD1a, anti-MMP-9, anti-MMP-13, and anti-TNF-α antibodies. The Mann-Whitney test and the Spearman correlation test were used for analysis of the data (P<0.05). RESULTS: The immunoexpression of MMP-13 and CD68 was significantly higher in RCs when compared with RRCs (P=0.011 and 0.012, respectively). The presence of an intense inflammatory infiltrate was significantly correlated with the immunoexpression of CD68 in RCs (P=0.025). Expression of CD68 showed a significant positive correlation with MMP-13 (P=0.015). A moderate correlation was observed between MMP-9 and MMP-13 (P=0.010). TNF-α expression was more common in RCs (P=0.001). CD1a was more frequently expressed in atrophic epithelium (P=0.041) and was significantly correlated with TNF-α (P=0.014). CONCLUSION: Langerhans cells induce a greater release of TNF-α which, in turn, is responsible for the stimulation of M1 macrophages. Higher immunoexpression of MMP-13 and MMP-9 is observed in the early stages of RCs compared with RRCs. Therefore, the toxins of microorganisms present in highly inflamed RCs are the main factors triggering a proinflammatory immune response and greater cystic expansion in the early stages of these lesions.