Detection of Cutibacterium acnes in Tissue Samples from Clean Primary Shoulder Surgeries - Part II / Detecção de Cutibacterium acnes em amostras de tecidos de cirurgias limpas primárias do ombro - Parte II

Abstract Objective Research and identification of Cutibacterium acnes (C. acnes) and other microorganisms in deeptissue samples collected in clean shoulder surgeries of patients who did not undergo any previous invasive joint procedure and who had no clinical history of infection. Methods We analyzed the results of cultures of intraoperative deep tissue samples from 84 patients submitted to primary clean shoulder surgery. Tubes containing culture medium were used for storage and transport of anaerobic agents, prolonged incubation time, and mass spectrometer for diagnosis of bacterial agents. Results Bacteria growth was evidenced in 34 patients (40.4%) of the 84 included in the study. Of these, 23 had growth of C. acnes in at least one sample of deep tissue collected, corresponding to 27.3% of the total patients. The second most common agent was Staphylococcus epidermidis, present in 7.2% of the total individuals included. We showed a higher relationship between sample positivity and males, a lower mean age, absence of diabetes mellitus, ASA I score, and antibiotic prophylaxis in anesthetic induction with cefuroxime. Conclusions A high percentage of isolates of different bacteria was found in shoulder tissue samples of patients undergoing clean and primary surgeries, who had no history of previous infection. Identification of C. acnes was high (27.6%), and Staphylococcus epidermidis was the second most frequent agent (7.2%).

Resumo Objetivo Pesquisa e identificação de Cutibacterium acnes (C. acnes) e de outros microrganismos em amostras de tecidos profundos coletados em cirurgias limpas de ombro em pacientes que não foram submetidos a nenhum procedimento invasivo articular prévio e que não possuíam antecedentes clínicos de infecção. Métodos Foram analisados os resultados das culturas de amostras de tecidos profundos intraoperatórias de 84 pacientes submetidos à cirurgia limpa primária do ombro. Foram utilizados tubos contendo meio de cultivo para armazenamento e transporte de agentes anaeróbicos, tempo prolongado de incubação e espectrômetro de massa para diagnósticos de agentes bacterianos. Resultados Foi evidenciado o crescimento de bactérias em 34 pacientes (40,4%) dos 84 incluídos no estudo. Desses, 23 apresentavam crescimento de C. acnes em pelo menos uma amostra de tecido profundo coletada, correspondendo a 27,3% do total de pacientes. O segundo agente mais encontrado foi o Staphylococcus epidermidis, presente em 7,2% do total de indivíduos incluídos. Evidenciamos maior relação da positividade de amostras com o gênero masculino, uma média de idade inferior, a ausência de diabetes mellitus, o escore ASA I e a profilaxia antibiótica na indução anestésica com cefuroxima. Conclusões Verificou-se um elevado percentual de isolados de diferentes bactérias em amostras de tecidos de ombros de pacientes submetidos a cirurgias limpas e primárias e sem histórico de infecção anterior. A identificação de C. acnes foi elevada (27,6%) e o Staphylococcus epidermidis foi o segundo agente mais frequente (7,2%).

A novel approach to Cestrum intermedium (mata-boi): anatomical and physical-chemical characterization, in vitro biological activities, and metabolites of a Brazilian native species

Abstract The Brazilian native species Cestrum intermedium, known as mata-boi, induces hepatotoxicity and death when ingested by cattle. While most studies on this species focus on toxicological features, our study is the first to describe the anatomy and in vitro biological activities of Cestrum intermedium. We investigated adult leaves and stems by histochemistry, described their anatomy, performed physical-chemical analysis, determined in vitro antioxidant and antimicrobial activities, and identified secondary metabolites. A few noteworthy anatomical features were the anomocytic stomata on the abaxial surface and the absence of trichomes, in addition to the circular shaped petiole with two projections on the adaxial surface. Histochemical analysis showed chemical markers such as alkaloids, usually reported as toxic, and terpenoids. Potassium nitrate (ATR-FTIR) and lupeol palmitate (NMR) were detected on the crude stem extract. Thermogravimetric and physical-chemical analysis provided fingerprint parameters for the species. Minimal Inhibitory Concentration (MIC) assay revealed that Staphylococcus aureus, Staphylococcus epidermidis, and Candida albicans were weakly inhibited by extract samples. Chloroform and ethyl acetate fractions presented high phenolic content, which resulted in in vitro antioxidant activity. These novel features expand the knowledge about this species, considering that previous studies mainly focused on its toxicity. Our study also provided characteristics that may help in avoiding misidentification between Cestrum members, especially when taxonomic keys cannot be employed, as in the absence of flowers and fruits.

Coagulase-negative staphylococci isolates from blood cultures of newborns in a tertiary hospital in southern Brazil

Abstract Neonatal sepsis continues to be a major cause of morbidity and mortality worldwide. Coagulase-negative staphylococci (CoNS), commonly found on the skin, being the main agents isolated. The aim of this study was to evaluate CoNS isolated from blood cultures of newborn (NB) infants. The study took place between 2014 and 2016/2017 in a tertiary hospital in southern Brazil. Using the VITEK 2 system (bioMérieux, Marcy l'Etoile, France), the microorganisms were identified and had their sensitivity profiles determined. The minimum inhibitory concentrations of linezolid, tigecycline, and vancomycin were also determined. The clinical parameters and mortality rates of NBs were evaluated. From January to December 2014, 176 CoNS isolates were obtained from 131 patients and from June 2016 to July 2017, 120 CoNS isolates were obtained from 79 patients. Staphylococcus epidermidis was most prevalent in both periods. Resistance rates increased between 2014 and 2016/2017, especially against ciprofloxacin (52.27% and 73.11%, p = 0.0004), erythromycin (51.40% and 68.07%, p = 0.0054), gentamicin (50.59% and 67.23%, p = 0.0052), and penicillin (71.3% and 99.17%, p = 0.0001), respectively. With 100% susceptibility to linezolid, tigecycline, and vancomycin in both periods and methodologies tested. In 2014, 53.44% of the NBs received antibiotic therapy, and of these, 77.14% used a catheter; in 2016/2017, these were 78.48% and 95.16%, respectively. Regarding laboratory tests, a hemogram was ineffective, since patients with sepsis presented normal reference values. In 2014 and 2016/17, 15.71% and 17.74% of the NBs died, respectively. S. epidermidis was the predominant microorganism, related to catheter use in most cases. The resistance rates have increased over time, demonstrating the importance of adopting control and prevention measures in this hospital. CoNS are responsible for a significant neonatal sepsis mortality rate in infants.

Characterization, Antioxidant and Antibacterial Potentials of Tamarindus indica L. Fruit Pulp Extract Loaded O/W Nanoemulsions

Abstract The main purposes of the current study were to formulate o/w nanoemulsions as a carrier for Tamarindus indica (tamarind) fruit pulp extract and to study the antioxidant and antibacterial potentials of nanoemulsions containing tamarind extract, focusing on cosmetic/hygiene applications. The o/w nanoemulsions using a mixture of Tween 80 and Span 80 as an emulsifier (5%w/w) were prepared by a high pressure homogenization process. Two concentrations of sweet tamarind extract, 3.3 and 6.6%w/w, based on the bioactivity study, were incorporated into the blank nanoemulsions to produce loaded nanoemulsions, F1-3.3TE (3.3%) and F1- 6.6TE (6.6%). As compared with the unloaded nanoemulsion, both tamarind extract loaded nanoemulsions showed reduced pH and significantly increased viscosity. Overall, the loaded nanoemulsions had droplet sizes of approximately 130 nm, zeta potential around -38 mV and polydispersity index (PDI) values less than 0.2. The nanoemulsion F1-3.3TE had better stability (e.g. significantly greater % tartaric acid content and lesser PDI value) than the nanoemulsion F1-6.6TE did. The antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl assay revealed that the nanoemulsions F1-3.3TE and F1-6.6TE had scavenging activities of 81.66 ± 0.77% and 63.80 ± 0.79%, respectively. However, antioxidant activity of these two formulations decreased under stress conditions (heating-cooling cycles). Such incidence did not occur for their antibacterial properties investigated by agar well diffusion technique. The two formulations exhibited inhibition zones of approximately 24.0-27.7 mm against Staphylococcus aureus and Staphylococcus epidermidis, responsible for malodor of underarms. The results suggest the potential of using sweet tamarind pulp extract loaded nanoemulsions as hygiene products.

Infecciones intrahospitalarias por estafilococo coagulasa negativo en una unidad de neonatología / Coagulase negative streptococci nosocomial infections at a neonatal intensive care unit / Infecções intra-hospitalares por estafilococo coagulasa negativa numa unidade de neonatologia

Introducción: la sepsis tardía por estafilococo coagulasa negativo (SCoN) es una causa común de morbimortalidad en la unidad neonatal. Los SCoN son los microorganismos más frecuentemente involucrados con aproximadamente el 50% de los casos. El objetivo de este estudio es analizar la incidencia y las características de los neonatos portadores de sepsis tardía por SCoN. Materiales y métodos: se realizó un estudio descriptivo, longitudinal, retrospectivo. Se utilizaron las bases de datos del laboratorio de microbiología del hospital y las historias clínicas electrónicas para obtener la información. El período de estudio analizado fueron los años 2018 y 2019 en la unidad de cuidados intensivos e intermedios de recién nacidos del Centro Hospitalario Pereira Rossell. Resultados: obtuvimos una incidencia de 2,5% de los ingresos a cuidados intensivos e intermedios (25 pacientes). La edad gestacional al nacer fue de 28 semanas (25,0-35,0) y la mediana del peso fue de 1.070 g (730,0-2.365,0). La media de edad gestacional posmenstrual al momento del diagnóstico fue de 32,92±7,921 semanas. Por sospecha de sepsis precoz, 17 pacientes habían recibido un curso de antibióticos previo. El signo clínico más frecuentemente observado fue el deterioro del estado general, en 11 pacientes, seguido de distensión abdominal en 6 y fiebre en 5. Dentro de los SCoN, el más frecuentemente aislado fue el Staphylococcus epidermidis (13 pacientes); 22 pacientes recibieron tratamiento, 18 de ellos con vancomicina-meropenem y 4 con monoterapia con vancomicina. Conclusión: estos patógenos representan una causa importante de morbimortalidad en la unidad neonatal, particularmente en pacientes que presentan mayor gravedad y mayor necesidad de soporte vital. Se necesitan pautas claras de interpretación del rol de estos microorganismos y de abordaje de pacientes con riesgo de sepsis tardía, incluyendo el tratamiento antibiótico empírico.

Introduction: Coagulase Negative Staphylococci (CoNS) late onset sepsis is a common cause of morbidity and mortality in the neonatal intensive care unit (NICU). CoNS are the most frequently isolated microorganisms and total 50% of cases. The objective of this study is to analyze the incidence and characteristics of newborns carriers of late onset CoNS. Materials and methods: we performed a descriptive, retrospective, longitudinal study. Data was obtained from the hospital's microbiology laboratory database and electronic medical records. Patients included were those admitted to NICU during the period between 2018 and 2019. Results: we obtained an incidence of 2.5% of patients admitted to the NICU (25 patients). Median gestational age at birth was 28 weeks 25.0-35.0 and median birth weight was 1.070 g 730.0-2365.0. Mean gestational age at the time of diagnosis was 32.92±7.921 weeks. 17 patients had received an antibiotics course at birth because of early onset sepsis suspicion. The most frequently observed clinical symptom was deterioration of general condition, 11 patients, followed by abdominal distention in 6 and fever in 5. Among CoNS, the most frequently isolated pathogen was Staphylococcus epidermidis (13 patients). 22 patients received treatment, 18 a combination of vancomycin and meropenem and 4 received vancomycin monotherapy. Conclusion: these pathogens are a common cause of morbidity and mortality in the newborn intensive care unit, particularly in patients with more serious conditions and in those who require more advanced life support measures. Clearer interpretation of their role is needed as well as to determine a proper approach to patients at risk of late onset sepsis, including empiric antibiotic treatment.

Sepse tardia para Staphylococcus coagulase negativa (SCoN) é uma causa comum de morbidade e mortalidade na unidade neonatal. SCoNs são os microrganismos mais frequentemente envolvidos e representam aproximadamente 50% dos casos. O objetivo deste estudo é analisar a incidência e as características de neonatos com sepse tardia por SCoN. Materiais e métodos: foi realizado um estudo descritivo, longitudinal e retrospectivo. Usamos os bancos de dados do laboratório de microbiologia e prontuários médicos eletrônicos de nosso hospital para obter as informações. O período de estudo analisado foi de 2018 e 2019 na unidade de terapia intensiva e intermediária para recém-nascidos do Centro Hospitalar Pereira Rossell. Resultados: obtivemos uma incidência de 2,5% de internações em Terapia Intensiva e Intermediária (25 pacientes). A idade gestacional ao nascer foi de 28 semanas 25,0-35,0 e o peso médio foi de 1070g 730,0-2365,0. A média da idade gestacional pós-menstrual no momento do diagnóstico foi de 32,92 ± 7,921 semanas. 17 pacientes haviam recebido um curso anterior de antibióticos por suspeita de sepse precoce. O sinal clínico mais frequentemente observado foi deterioração do estado geral em 11 pacientes, seguido por distensão abdominal em 6 e febre em 5. Dentre os SCoN, o mais isolado foi o Staphylococcus Epidermidis (13 pacientes). 22 pacientes receberam tratamento, 18 deles com Vancomicina-Meropenem e 4 com Vancomicina em monoterapia. Conclusão: esses patógenos representam uma importante causa de morbimortalidade na unidade neonatal, principalmente em pacientes com maior gravidade e maior necessidade de suporte de vida. Orientações claras são necessárias para interpretar o papel desses microrganismos e para abordar pacientes com risco de sepse tardia, incluindo tratamento com antibióticos.

Staphylococcus coagulasa negativos como causantes de endocarditis en un recién nacido pretérmino / Neonatal coagulase negative Staphylococcus as a cause of endocarditis / Staphylococcus coagulase negativa como causa de endocardite em recém-nascido prematuro

Los estafilococos coagulasa negativos son microorganismos frecuentemente aislados cuya significancia clínica puede ser difícil de establecer por su carácter de comensales habituales de la piel. En la población neonatal estos patógenos han ido adquiriendo mayor protagonismo debido a la sobrevida de pacientes mas prematuros que en el pasado, así como sus necesidades de tratamiento, que determinan mayores tiempos de estadía hospitalaria. Estos elementos representan factores de riesgo también para el desarrollo de endocarditis en estos pacientes, particularmente debido a la utilización de catéteres intravasculares centrales por tiempo prolongado. En este caso clínico se presenta un paciente pretérmino severo que presentó una endocarditis a estafilococo coagulasa negativo a partir del cual discutiremos las características de las infecciones por estos microorganismos, las características de la endocarditis infecciosa en el recién nacido pretérmino y la utilización de antibióticos en estos pacientes, así como algunos elementos asociados a la vigilancia activa en el uso de antibióticos.

Coagulase negative staphylococcus (CoNS) are commonly isolated microorganisms whose clinical importance may be difficult to establish due to their role as part of our usual skin microbiota. These pathogens have gained relevance in neonatal population due to an improvement in neonatal care that determine longer survival rates and hospitals stays. Neonatal endocarditis is also affected by these microorganisms and particularly by the use of central intra vascular lines for long periods of time. In this clinical case we introduce a severe preterm patient who developed a CoNS endocarditis and discuss the characteristics of CoNS infections and endocarditis in preterm newborns as well as some antibiotic vigilance principles.

Os estafilococos coagulase negativos são microrganismos frequentemente isolados, cujo significado clínico pode ser difícil de estabelecer devido ao seu caráter de comensais cutâneos comuns. Na população neonatal, esses patógenos vêm adquirindo maior destaque devido à sobrevida de pacientes mais prematuros do que no passado, bem como suas necessidades de tratamento, as quais determinam tempos de internação mais longos. Esses elementos também representam fatores de risco para o desenvolvimento de endocardite nesses pacientes, principalmente pelo uso prolongado de cateter intravascular central. Neste caso clínico apresentaremos um paciente pré-termo grave que apresentou endocardite estafilocócica coagulase-negativa a partir do qual discutiremos as características das infecções por esses microrganismos, as características da endocardite infecciosa no recém-nascido pré-termo e o uso de antibióticos nesses pacientes bem como alguns elementos associados à vigilância ativa no uso de antibióticos.

Demanda de culturas microbiológicas e prevalência de microrganismos em um hospital universitário de Pernambuco / Demand for microbiological cultures and prevalence of microorganisms in a university hospital of Pernambuco / Demanda de culturas microbiológicas y prevalencia de microrganismos en un hospital universitario de Pernambuco

Objetivo: verificar a demanda de hemoculturas, aspirados traqueais e uroculturas realizadas no HU-UNIVASF/ EBSERH e a prevalência dos microrganismos identificados no período de janeiro a junho de 2016. Métodos: estudo retrospectivo documental com abordagem quantitativa. Resultados: o setor de microbiologia realizou 488 hemoculturas, 427 uroculturas e 197 aspirados traqueais. A positividade de hemoculturas mostrou-se entre 10,9 à 25,7%, e o percentual de contaminações variou de 6,8 à 14,0%. Os microrganismos mais prevalência nas hemoculturas foram Staphylococcus epidermidis (23,7%), Staphylococcus aureus (19,3%) e Klebisiella pneumoniae (9,6%). Nas uroculturas foram Klebisiella pneumoniae (23,1%), Candida sp. (13,5%) e Escherichia coli (12,5%). Nos aspirados traqueais foram Acinetobacter baumannii (29,2%), Pseudomonas aeruginosa (26,6%) e Staphylococcus aureus (16,2%). Conclusão: a cultura mais solicitada foi hemocultura. A bactéria mais prevalente nas hemoculturas foi Staphylococcus epidermidis, nos aspirados traqueais Acinetobacter baumannii e nas uroculturas Klebisiella pneumoniae

Objective: the study's purpose has been to verify the demand for blood cultures, tracheal aspirates and urine cultures performed at a University Hospital from the Universidade Federal do Vale do São Francisco (HU-UNIVASF/EBSERH), as well as the predominance of microorganisms identified over the period from January to June 2016. Methods: it is a retrospective documentary study with a quantitative approach. Results: the microbiology sector carried out 488 blood cultures, 427 urine cultures and 197 tracheal aspirates. The positivity of blood cultures was between 10.9 and 25.7%, and the percentage of contaminations ranged from 6.8 to 14.0%. The most prevalent microorganisms in blood cultures were Staphylococcus epidermidis (23.7%), Staphylococcus aureus (19.3%) and Klebsiella pneumoniae (9.6%). In urine cultures were Klebsiella pneumoniae (23.1%), Candida sp. (13.5%) and Escherichia coli (12.5%). In tracheal aspirates were Acinetobacter baumannii (29.2%), Pseudomonas aeruginosa (26.6%) and Staphylococcus aureus (16.2%). Conclusion: the most requested culture was blood culture. The most prevalent bacterium in blood cultures was Staphylococcus epidermidis, in tracheal aspirates was Acinetobacter baumannii, and in urine cultures was Klebsiella pneumoniae

Objetivo: el propósito del trabajo es verificar la demanda de hemocultivos, aspirados traqueales y urocultivos realizados en el Hospital Universitário de la Universidade Federal do Vale do São Francisco (HU-UNIVASF/ EBSERH) y la prevalencia de los microorganismos identificados en el período de enero a junio de 2016. Métodos: este trabajo es un estudio retrospectivo documental con abordaje cuantitativo. Resultados: el sector de microbiología realizó 488 hemocultivos, 427 urocultivos y 197 aspirados traqueales. La positividad de hemocultivos se mostró entre el 10,9 al 25,7%, y el porcentaje de contaminaciones varía de 6,8 a 14,0%. Los microorganismos más prevalentes en los hemocultivos fueron Staphylococcus epidermidis (23,7%), Staphylococcus aureus (19,3%) y Klebsiella pneumoniae (9,6%). En los urocultivos fueron Klebisiella pneumoniae (23,1%), Candida sp. (13,5%) y Escherichia coli (12,5%). En los aspirados traqueales fueron Acinetobacter baumannii (29,2%), Pseudomonas aeruginosa (26,6%) y Staphylococcus aureus (16,2%). Conclusión: la cultura más solicitada fue hemocultivo. La bacteria más prevalente en los hemocultivos fue Staphylococcus epidermidis, en los aspirados traqueales, Acinetobacter baumannii y en los urocultivos, Klebisiella pneumoniae

Infection of expanded polytetrafluoroethylene and Dacron-coated stents with Staphylococcus epidermidis: an experimental study in pigs / Infecção de stents revestidos com politetrafluoretileno expandido e Dacron com Staphylococcus epidermidis: estudo experimental em porcos

Abstract Background Diagnosis of the etiologic agent of endoprosthesis infections is essential to enable treatment, since these infections constitute important complications of endovascular procedures. Sonication of explanted tissue and materials is a technique that can be used to facilitate detection of biofilm-producing bacteria. Objectives To evaluate infection of pigs' aortas after implantation of nitinol stents coated with polytetrafluoroethylene (ePTFE) or Dacron, previously infected with biofilm-producing Staphylococcus epidermidis. Intimal thickening and the inflammatory response in the aortic wall were also evaluated. Methods 11 ePTFE-coated nitinol stents and 10 Dacron stents infected with S. epidermidis strains were implanted in the infrarenal aorta of 21 8-week-old pigs. After 2 weeks, the aorta containing the stents was removed. A vortex mixer and ultrasound were used to homogenize the samples and remove the biofilm. Subsequently, the number of colony-forming units was counted. Results There were no significant differences between the two groups in terms of the number of colony-forming units or of inflammation in the arterial wall. With the exception of one specimen from the Dacron group, all aortic stent cultures were positive for S. epidermidis. Conclusions There were no significant differences in the inflammatory response or infection rate between ePTFE and Dacron-coated stents actively infected with biofilm-producing S. epidermidis. Intimal thickening and the inflammatory response to infection of endoprostheses were similar. These results suggest that the two most widely used stent lining materials have a similar infection rate.

Resumo Contexto O diagnóstico do agente etiológico é essencial para o tratamento das infecções de endoprótese, pois representam uma importante complicação do tratamento endovascular. A sonificação dos tecidos pode ser uma técnica usada para auxiliar na detecção de bactérias produtoras de biofilme. Objetivos Avaliar a infecção da aorta dos porcos após o implante de stents de nitinol revestidos com politetrafluoretileno (ePTFE) ou Dacron, infectados com Staphylococcus epidermidis, produtor de biofilme. O espessamento intimal e a resposta inflamatória na parede aórtica também foram avaliados. Métodos Onze stents de nitinol revestidos com ePTFE e 10 stents de Dacron infectados com cepas de S. epidermidis foram implantados na aorta infrarrenal de 21 porcos com 8 semanas de idade. Após duas semanas, a aorta contendo os stents foi removida. Um misturador de vórtice e ultrassom foram utilizados para homogeneizar as amostras e remover o biofilme. Posteriormente, o número de unidades formadoras de colônias foi contado. Resultados Não houve diferenças significativas no número de unidades formadoras de colônias ou inflamação na parede arterial entre os dois grupos. Todas as culturas de stent aórtico foram positivas para S. epidermidis, exceto uma no grupo Dacron. Conclusões Não houve diferenças significativas na resposta inflamatória ou na taxa de infecção entre os stents revestidos de ePTFE e Dacron, infectados ativamente pelo S. epidermidis produtor de biofilme. O espessamento intimal e a resposta inflamatória à infecção das endopróteses foram semelhantes. Esses resultados sugerem que os dois materiais de revestimento de stent mais amplamente utilizados têm uma taxa de infecção semelhante.

Synergistic antibacterial activity of monoterpenes in combination with conventional antimicrobials against Gram-positive and Gram-negative bacteria / Atividade antibacteriana sinérgica de monoterpenos combinados com antimicrobianos convencionais frente a bactérias Gram-positivas e Gram-negativas

Introduction: bacterial infections are a public health problem. Besides, the emergence of strains resistant to antimicrobials has contributed to the search for new alternatives, such for the terpenes with antimicrobial potential. Objectives: the objective of this study was to determine the possible interaction of isolated monoterpenes (-)-Carveol, Geraniol, Citronellol, α-terpineol, R-(-) Carvone, (-)-Menthol, Linalool, D-Dihydrocarvone, and (-)-Terpine-4-ol with conventional antimicrobials (Chloramphenicol, Minocycline, Amoxicillin and Ciprofloxacin) when they are evaluated on Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa strains. Methodology: the minimum inhibitory concentrations of these test drugs were determined using the microdilution method. The Checkerboard method was used to assess the interactions, by determining the fractional inhibitory concentration index (FIC index). Results: aamong the monoterpenes, only Carveol, Citronellol, and Geraniol presented antimicrobial activity (MIC < 1024 µg/mL). They presented synergistic effects against Pseudomonas aeruginosa ATCC-9027 (FIC index ≤ 0.5) when in combination with Minocycline. Conclusion: this study contributes to the development of new approaches to control bacterial resistance and to the possibility of discovering new drugs.

Introdução: as infecções bacterianas são um problema de saúde pública. Além disso, o surgimento de cepas resistentes aos antimicrobianos tem contribuído para a busca de novas alternativas, como a pesquisa de terpenos com potencial antimicrobiano. Objetivos: o objetivo deste estudo foi determinar a possível interação de monoterpenos isolados (-) - Carveol, Geraniol, Citronelol, α-terpineol, R - (-) Carvona, (-)-Mentol, Linalol, D-Diidrocarvona e (-)-Terpina-4-ol com antimicrobianos convencionais (cloranfenicol, minociclina, amoxicilina e ciprofloxacina) quando avaliados em Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Escherichia coli e Pseudomonas aeruginosa. Metodologia: as concentrações inibitórias mínimas destas drogas foram determinadas usando o método de microdiluição. O método checkerboard foi utilizado para avaliar as interações, determinando o índice de concentração inibitória fracionária (índice FIC). Resultados: entre os monoterpenos, apenas Carveol, Citronelol e Geraniol apresentaram atividade antimicrobiana (CIM < 1024 µg/mL). Eles apresentaram efeitos sinérgicos contra Pseudomonas aeruginosa ATCC-9027 (índice FIC ≤ 0,5) quando em combinação com Minociclina. Conclusão: este estudo contribui para o desenvolvimento de novas abordagens para o controle da resistência bacteriana e para a possibilidade de descoberta de novas drogas.

In vitro effectiveness of an aqueous extract of neem (azadirachta indicaa. juss) leaves on bacteria causing healthcare associated infection in Valledupar / Efectividad in vitrodel extracto de hojas de neem (azadirachta indicaa. juss) sobre bacterias causantes de infecciónes asociadas a la atención sanitaria en Valledupar

Background: Globally,the need to address strategies for preventing infections associated with health care has increased worldwide. In the city of Valledupar, Colombia, reports of bacteria resistant to chemical or enzymatic biocides in hospital environments and surfaces are increasingly frequent, evidencing the importance of conducting studies aimed at identifying alternative active ingredients for disinfectant products. Objective: Evaluate the in vitro effectiveness of Neem leaves extract over bacteria strains isolated from different areas and surfaces of a health institution in Valledupar, compared to disinfectants for hospital use, an enzymatic detergent, and a commercial chemical disinfectant. Methods: Biocidal activities on bacteria isolated from hospital surfaces, such as Acinetobacter baumanni, Bacillus subtilis, Enterobacter aerogenes, Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus sp, and Stenotrophomonas maltophilia were analyzed. The Neem leaves extract was evaluated at concentrations of 3, 4, and 5 % for each bacterium during 15-minute contact time, incubated at 37 °C for 18 hours. We compared two antimicrobial chemicals, a disinfectant (based on formaldehyde, cetrimide, and glutaraldehyde), and an enzymatic detergent (based on protease, lipase, and amylase). Results: The aqueous Neem extract did not show significant differences with the other treatments with 99.48 to 100% inhibition against bacteria of the species Acinetobacter baumanni, Enterobacter aerogenes, Staphylococcus aureus,and Micrococcus sp.; Bacillus subtilis, and Stenotrophomonas maltophilia strains were the most resistant strains inhibited by enzymatic detergent and disinfectant, respectively. None of the products evaluated were effective against all in vitro strains. Conclusions: These data show Neem's bacteriostatic properties, its potential in in-hospital products and the need to combine different active ingredients in a disinfection plan.

Antecedentes: A nivel mundial ha aumentado la necesidad de abordar estrategias para la prevención de infecciones asociadas a la atención de salud. En la ciudad de Valledupar, Colombia, cada vez son más frecuentes los reportes de bacterias resistentes a biocidas químicos o enzimáticos, en ambientes y superficies hospitalarias, lo cual evidencia la importancia de realizar estudios orientados a la identificación de principios activos alternativos para productos desinfectantes. Objetivo: Evaluar la efectividad in vitrodel extracto de hojas de Neem en cepas de bacterias aisladas en diferentes áreas y superficies de una institución de salud en Valledupar, en comparación con desinfectantes de uso hospitalario, un detergente enzimático y un desinfectante químico comercial. Métodos: Se analizó la actividad biocida sobre las bacterias aisladas de superficies hospitalarias Acinetobacter baumanni, Bacillus subtilis, Enterobacter aerogenes, Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus sp, y Stenotrophomonas maltophilia. El extracto de hojas de Neem se evaluó a concentraciones de 3, 4 y 5% para cada bacteria durante un tiempo de contacto de 15 minutos, incubados a 37 ° C durante 18 horas. Se comparó dos productos químicos antimicrobianos, un desinfectante (a base de formaldehído, cetrimide y glutaraldehído), y un detergente enzimático (a base de Proteasa, Lipasa y amilasa). Resultados: El extracto acuoso de Neem no presentó diferencias significativas con los demás tratamientos con inhibición del 99,48 al 100%, sobre bacterias de las especies Acinetobacter baumanni, Enterobacter aerogenes, Staphylococcus aureus y Micrococcus sp; las cepas Bacillus subtilisy Stenotrophomonas maltophilia fueron las más resistentes a ser inhibidas por el detergente enzimático y el desinfectante, respectivamente. Ninguno de los productos evaluados fue efectivo contra todas las cepas in vitro. Conclusiones: Estos datos evidencian las propiedades bacteriostáticas del Neem, su potencial en productos de uso intrahospitalario y la necesidad de combinar diferentes principios activos en un plan de desinfección.

Patología infecciosa del vestíbulo nasal / Infectious diseases of the nasal vestibule

El vestíbulo nasal corresponde a la primera porción de la fosa nasal, éste se encuentra delimitado lateralmente por los cartílagos alares y medialmente por el borde caudal del septum nasal y la columela. Las enfermedades infecciosas del vestíbulo nasal son patologías frecuentes en la práctica clínica; su diagnóstico se realiza en base a sospecha clínica y examen físico, requiriendo habitualmente solo manejo médico ambulatorio. Desde el punto de vista etiológico pueden ser virales, bacterianas y fúngicas. Las principales especies bacterianas involucradas corresponden a Staphylococcus coagulasa negativa, S. epidermidis, S. hominis y S. haemolyticus, difteroides spp y S. aureus. Su manejo es esencialmente médico con casos excepcionales requiriendo manejo quirúrgico. En la actualidad existe escasa información epidemiológica al respecto, lo que dificultad la clasificación de los dichos cuadros clínicos. Se realizó una revisión de la literatura sobre cuadros infecciosos que afectan el vestíbulo nasal para lograr sistematizar y clarificar las distintas patologías y sus tratamientos.

The nasal vestibule corresponds to the first portion of the nasal passage, limited laterally by the lateral crus and medially by the caudal edge of the nasal septum and columella. Infectious diseases of the nasal vestibule are frequent in clinical practice, diagnosis is made based on clinical suspicion and physical examination, usually requiring only ambulatory medical management. In terms of etiology, they can be viral, bacterial and fungal. The main bacterial species involved correspond: Coagulase-negative Staphylococcus, S. epidermidis, S. hominis and S. haemolyticus, difteroides spp and S. aureus. Management is essentially medical and only exceptionally requires surgery. Currently, there is a lack of epidemiological information in this regard, which makes it difficult to classify these clinical conditions. A review of the literature on infectious conditions that affect the nasal vestibule was performed, to systematize and clarify the different pathologies and their management.

Bacteremia in the red blood cells obtained from the cell saver in patients submitted to heart surgery / Bacteremia nos glóbulos vermelhos obtidos do "cell saver" em pacientes submetidos a cirurgia cardíaca / Bacteriemia en los glóbulos rojos obtenidos del "cell saver" en pacientes intervenidos de cirugía cardíaca

Objective: to determine the microbiological characteristics of the red blood cells obtained with the cell saver in heart surgery patients on an extra-body circuit. Method: a cross-sectional and descriptive study conducted with 358 patients scheduled for heart surgery where the saver was used. Sociodemographic variables were collected, as well as from the saver and of the microbial identification in the re-infusion bag proceeding from the cell saver. Informed consent performed. Results: of the 170 GRAM+ bacteria isolations, the most frequent species were Staphylococcus epidermidis in 69% (n=138) of the cases and Streptococcus sanguinis with a report of 10% (n=20). Significant differences were found in the Staphylococcus epidermidis strain in patients with a Body Mass Index ≥25 (p=0.002) submitted to valve surgery (p=0.001). Vancomycin was the antimicrobial which resisted the Staphylococcus epidermidis strain with a minimum inhibitory concentration of >16 µg/ml. Conclusion: the microbiological characteristics of the red blood cells obtained after processing autologic blood recovered with the cell saver during heart surgery are of GRAM+ bacterial origin, the most isolated species being Staphylococcus epidermidis. Consequently, in order to reduce the presence of these GRAM+ cocci, an antibiotic should be added to the cell saver reservoir, according to a previously established protocol.

Objetivo: determinar as características microbiológicas dos glóbulos vermelhos obtidos com o "cell saver" em pacientes submetidos à cirurgia cardíaca em circuito extracorpóreo. Método: estudo descritivo transversal com 358 pacientes de cirurgia cardíaca em que o "cell saver" foi utilizado. Foram coletadas variáveis sociodemográficas e identificação microbiana da bolsa de reinfusão do "cell saver". Foi confirmado o Termo de Consentimento. Resultados: das 170 baterias isoladas GRAM+, as mais frequentes foram Staphylococcus epidermidis em 69% (n=138) dos casos e Streptococcus sanguinis com um registro de 10% (n=20). Diferenças significativas foram encontradas na cepa Staphylococcus epidermidis em pacientes com índice de massa corporal ≥25 (p=0,002) submetidos a cirurgia valvular (p=0,001). A vancomicina foi o antimicrobiano resistente à cepa Staphylococcus epidermidis com uma concentração inibitória mínima >16 µg/ml. Conclusão: as características microbiológicas dos glóbulos vermelhos obtidas após o processamento do sangue autólogo recuperado com o "cell saver" em cirurgia cardíaca são de origem bacteriana GRAM+, sendo a espécie mais isolada o Staphylococcus epidermidis. Portanto, para reduzir a presença desses cocos GRAM+, um antibiótico deve ser adicionado ao "cell saver", de acordo com um protocolo previamente estabelecido.

Objetivo: determinar las características microbiológicas de los glóbulos rojos obtenidos con el "cell saver" en el paciente de cirugía cardíaca bajo un circuito extracorpóreo. Método: estudio descriptivo transversal con 358 pacientes programados para cirugía cardíaca donde se utilizó el "cell saver". Se recogieron variables sociodemográficas e identificación microbiana de la bolsa de reinfusión procedente del "cell saver". Consentimiento informado realizado. Resultados: de 170 aislamientos de bacterias GRAM+, las especies más frecuentes fueron el Staphylococcus epidermidis en el 69% (n=138) de los casos y el Streptococcus sanguinis con un reporte del 10% (n=20). Se encontraron diferencias significativas en la cepa Staphylococcus epidermidis en pacientes con índice de masa corporal ≥25 (p=0,002) sometidos a cirugía valvular (p=0,001). La vancomicina fue el antimicrobiano resistente a la cepa Staphylococcus epidermidis con una concentración mínima inhibitoria >16 ug/ml. Conclusión: las características microbiológicas de los glóbulos rojos obtenidos tras el procesamiento de sangre autóloga recuperada con el "cell saver" en cirugía cardíaca son de origen bacteriano GRAM+ siendo la especie más aislada el Staphylococcus epidermidis. Por ello, con el fin de reducir la presencia de estos cocos GRAM+ se debería añadir un antibiótico en el reservorio del "cell saver", según un protocolo previamente establecido.

Characteristics of oral methicillin-resistant Staphylococcus epidermidis isolated from dental plaque / 国际口腔科学杂志·英文版

The oral microbial community is widely regarded as a latent reservoir of antibiotic resistance genes. This study assessed the molecular epidemiology, susceptibility profile, and resistance mechanisms of 35 methicillin-resistant Staphylococcus epidermidis (MRSE) strains isolated from the dental plaque of a healthy human population. Broth microdilution minimum inhibitory concentrations (MICs) revealed that all the isolates were nonsusceptible to oxacillin and penicillin G. Most of them were also resistant to trimethoprim (65.7%) and erythromycin (54.3%). The resistance to multiple antibiotics was found to be largely due to the acquisition of plasmid-borne genes. The mecA and dfrA genes were found in all the isolates, mostly dfrG (80%), aacA-aphD (20%), aadD (28.6%), aphA3 (22.9%), msrA (5.7%), and the ermC gene (14.3%). Classical mutational mechanisms found in these isolates were mainly efflux pumps such as qacA (31.4%), qacC (25.7%), tetK (17.1%), and norA (8.6%). Multilocus sequence type analysis revealed that sequence type 59 (ST59) strains comprised 71.43% of the typed isolates, and the eBURST algorithm clustered STs into the clonal complex 2-II(CC2-II). The staphyloccoccal cassette chromosome mec (SCCmec) type results showed that 25 (71.43%) were assigned to type IV. Moreover, 88.66% of the isolates were found to harbor six or more biofilm-associated genes. The aap, atlE, embp, sdrF, and IS256 genes were detected in all 35 isolates. This research demonstrates that biofilm-positive multiple-antibiotic-resistant ST59-SCCmec IV S. epidermidis strains exist in the dental plaque of healthy people and may be a potential risk for the transmission of antibiotic resistance.

Minocycline and Its Impact on Microbial Dysbiosis in the Skin and Gastrointestinal Tract of Acne Patients

Caracterización de pacientes pediatricos con hemocultivos positivos del servicio de cuidado intensivo pediatrico del Hospital San José Bogotá, abril 2012 a 2017 / Description of Pediatric Patients with Positive Blood Cultures from the Pediatric Intensive Care Unit at Hospital de San José in Bogotá, April 2012 to 2017

Introducción: El cultivo de la sangre es el método más utilizado en la búsqueda de infecciones del paciente pediátrico porque orienta la terapia antimicrobiana. Objetivo: Determinar la incidencia de hemocultivos positivos y su caracterización microbiológica en pacientes de cuidado intensivo pediátrico del Hospital de San José, Bogotá-Colombia. Materiales y métodos: Descripción de hemocultivos positivos en pacientes pediátricos de la unidad desde abril de 2012 a 2017. Se determinó la incidencia de hemocultivos positivos y se describió la población estudiada y los gérmenes aislados incluido su perfl de antibiograma. Resultados: Ingresaron 1773 pacientes a la UCIP, 241 pacientes (13,6%) fueron hemocultivados, de los cuales 80 (33,2%) fueron positivos, pero 50% de estos fueron catalogados como contaminaciones. La mediana de edad fue de 21 meses, con 64% de sexo masculino. El 57% fue ventilado y 45% tuvieron un catéter central. La mortalidad fue de 15,4%. La patología más frecuentemente fue respiratoria (75%). De los gérmenes no contaminantes el más frecuente aislado fue Staphylococcus aureus (30%), seguido de Klebsiella pneumoniae (17,5%) y Streptococcus pneumoniae (17,5%). El germen contaminante más frecuente fue Staphylococcus epidermidis (47,5%). Conclusión: La frecuencia de hemocultivos positivos es baja y es frecuente que se aíslen gérmenes contaminantes. El patrón fue similar a lo reportado por la red GREBO.

Introduction. Blood culture is the method most used in the search for pediatric infections because it guides the antimicrobial therapy. Objective. To determine the incidence of positive blood cultures and their microbiological characterization in patients of the pediatric intensive care service of San José Hospital, Bogotá-Colombia. Materials and methods: Description of positive blood cultures in pediatric patients of the unit from April 2012 to 2017. The incidence of positive blood cultures was determined and the population studied and the isolated germs were described, including their antibiogram profle. Results: 1773 patients were admitted to the PICU, 241 patients (13.6%) were blood cultures, of which 80 (33.2%) were positive, but 50% of these were classifed as contaminations. The median age was 21 months, with 64% male. 57% were ventilated and 45% had a central catheter. Mortality was 15.4%. The most frequent pathology was respiratory (75%). Of the non-polluting organisms, the most frequent isolate was Staphylococcus aureus (30%), followed by Klebsiella pneumoniae (17.5%) and Streptococcus pneumoniae (17.5%). The most frequent contaminant was Staphylococcus epidermidis (47.5%). Conclusion: The frequency of positive blood cultures is low and polluting organisms are often isolated. The pattern was similar to that reported by the GREBO network.

Associação entre Staphylococcus epidermidis e o nível de ácido palmítico em pacientes com acne vulgar / The association between Staphylococcus epidermidis and palmitic acid level in patients with acne vulgaris

INTRODUÇÃO: A acne vulgar é um distúrbio inflamatório da glândula pilossebácea. O ácido palmítico é um dos principais tipos de ácidos graxos livres e pode desempenhar um papel na patogênese da acne. Além disso, estudos recentes sugeriram que o Staphylococcus epidermidis pode estar envolvido na acne. OBJETIVO: Explorar a associação entre a Staphylococcus epidermidis e o ácido palmítico na acne vulgar. MÉTODOS: 43 estudantes do ensino médio de uma área urbana do sul de Sulawesi, na Indonésia, foram incluídos. O nível de ácido palmítico foi medido utilizando cromatografia gasosa e os comedões foram cultivados para detectar o perfil do microbioma. O teste de Mann-Whitney foi utilizado para analisar a diferença do nível palmítico médio entre os grupos com diferentes graus de gravidade da acne vulgar. RESULTADOS: 14 pacientes (32,6%) apresentavam acne vulgar leve, enquanto 14 e 15 pacientes apresentavam acne vulgar moderada e grave, respectivamente. O grupo grave e moderado apresentou nível de ácido palmítico significativamente maior em comparação ao grupo leve. A análise de subgrupo de pacientes com acne vulgar moderada e grave, positiva para S. epidermidis, mostrou um nível significativamente maior de ácido palmítico comparado ao grupo leve. CONCLUSÕES: Esses resultados sugerem que S. epidermidis pode estar associado ao nível de ácido palmítico e pode contribuir na patogênese da acne.

INTRODUCTION: Acne vulgaris is an inflammatory disorder of the pilosebaceous gland. Palmitic acid is one of the major types of free fatty acid and may play a role in acne pathogenesis. In addition, recent studies suggested that Staphylococcus epidermidis might be involved in acne. OBJECTIVE: To explore the association between Staphylococcus epidermidis and palmitic acid in acne vulgaris. METHODS: Forty-three high school students at an urban area in South Sulawesi, Indonesia, were included. The palmitic acid level was measured using gas chromatography and comedone was cultured to detect the microbiota profile. Mann-Whitney test was used to analyze the median palmitic level diference between groups with different acne vulgaris severity. RESULTS: Fourteen patients (32.6%) had mild acne vulgaris, while 14 and 15 patients had moderate and severe acne vulgaris, respectively The severe and moderate group showed significantly higher palmitic acid level compared with the mild group. Subgroup analysis of patients with moderate and severe acne vulgaris positive for S. epidermidis showed a significantly higher palmitic acid level compared with the mild group. CONCLUSIONS: This result suggests that S. epidermidis may be associated with the palmitic acid level and may contribute to acne pathogenesis.

Diagnostic value of pediatric blood culture bottles for acute postoperative endophthalmitis

OBJECTIVE: To report our experience using conventional culture methods (CM) and pediatric blood culture bottles (PBCBs) for vitreous sample culture of acute postoperative endophthalmitis. METHODS: A retrospective study was conducted at the Department of Ophthalmology, Hospital das Clinicas, HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, BR, from January 2010 to December 2015, and it included 54 patients with clinically suspected acute postoperative endophthalmitis. Vitreous samples were obtained by vitreous tap or vitrectomy. Samples from January 2010 to December 2011 were cultivated in CM, whereas samples from January 2012 to December 2015 were inoculated in PBCBs. The measured outcome was the yield of positive cultures. RESULTS: Twenty cases were included in the CM group, and 34 cases were included in the PBCB group. The yield of positive cultures in PBCBs (64.7%) was significantly higher than that in conventional CM (35%, p=0.034). Staphylococcus epidermidis and Streptococcus viridans were the two most commonly found agents. CONCLUSION: PBCBs can be used successfully in clinically suspected endophthalmitis. The method showed a higher yield of positive cultures than the conventional method. This technique appears to have several advantages over the traditional method: it saves time, as only one medium needs to be inoculated; transportation to a laboratory is easier than in the traditional method, and there is no need to maintain a supply of fresh agar media. The use of PBCBs may be recommended as the primary method for microbiological diagnosis and is especially suitable for office settings and remote clinics.

Eficácia da limpeza manual versus automatizada para a remoção de Staphylococcus epidermidis aderido à superfície de instrumental cirúrgico em diferentes intervalos por contaminação experimental / Efficacy of manual versus automated cleaning for the removal of Staphylococcus epidermidis adhered to the surface of surgical instruments at different intervals due to experimental contamination

Ao longo de sua vida útil, instrumentais cirúrgicos são submetidos a sucessivos ciclos de contaminação e processamento. A presença em áreas de difícil acesso, como serrilha e cremalheira, assim como a adoção de práticas inadequadas, durante a prélimpeza e a limpeza, pode dificultar a remoção de resíduos a cada reúso, favorecendo a formação de biofilme. Amplamente isolados como contaminantes de instrumentais cirúrgicos, após o uso, Staphylococcus epidermidis são reconhecidos pela sua capacidade de formar biofilme em diferentes superfícies. Neste sentido, questiona-se: como os métodos de limpeza manual e automatizada atuam na remoção de S. epidermidis aderido à superfície de instrumental cirúrgico submetido à contaminação experimental por diferentes intervalos? Objetivou-se comparar dois protocolos de limpeza, manual e automatizada, quanto à capacidade de remoção de S. epidermidis da superfície de instrumental cirúrgico submetido a diferentes intervalos de contaminação. Tratou-se de uma pesquisa experimental, realizada no Laboratório de Microbiologia Oral e Anaeróbios do Instituto de Ciências Biológicas da Universidade Federal de Minas Gerais (ICB/UFMG) e no centro de microscopia da UFMG. Foram selecionadas pinças do tipo crile reta, para a análise de áreas com diferentes desafios ao processo de limpeza: superfície irregular (serrilha e cremalheira) e lisa (haste). Os corpos de prova foram contaminados por imersão em Triptical Soya Broth (TSB), contendo 106 UFC/mL de uma amostra clínica de S. epidermidis. A aderência bacteriana, logo após a contaminação e a capacidade de remoção desses microrganismos, submetidos à limpeza manual ou automatizada, foram verificadas depois de uma, duas, quatro, seis, oito e 12 horas. Os resultados foram avaliados por meio de cultura microbiológica e pela microscopia eletrônica de varredura (MEV). A análise dos resultados ocorreu pelo emprego de técnicas de estatística descritiva e análise de variância (ANOVA) em nível de confiança de 5%. No grupo submetido à contaminação, a carga bacteriana apresentou aumento, ao longo do tempo, variando entre 101­102 UFC/cm2 após uma hora e 104 UFC/cm2 em 12 horas. Verificou-se aderência bacteriana, depois de uma hora, com a formação de biofilme após duas horas e, em geral, um aumento na concentração de microrganismos nos tempos subsequentes. A carga microbiana foi reduzida em 1-2 log10 após limpeza manual e entre 1-3 log10 depois de limpeza automatizada, sendo significativa (p<0,05) em todos os fragmentos e tempos avaliados neste último grupo. A análise, por meio de MEV, demostrou a permanência de biofilme após ambos os métodos. Em geral, fragmentos de haste apresentaram menor carga microbiana, nos diferentes grupos avaliados, sendo essa diferença significativa (p<0,05) ao tempo de seis horas. Concluiu-se que S. epidermidis apresentou a capacidade de aderência rápida levando à formação de biofilme após duas horas de contato com o instrumental cirúrgico com carga bacteriana de 102 UFC/cm2. A limpeza automatizada foi mais efetiva que a limpeza manual, contudo nenhum dos métodos removeu o biofilme formado completamente. As condições de pré-limpeza, bem como a presença em áreas de difícil acesso, como cremalheira e serrilha, são fatores críticos à qualidade do processamento de instrumentais cirúrgicos.

Surgical instruments are subjected to successive contamination and processing cycles throughout their useful life. The presence of areas of difficult access, such as serration and rack, as well as the adoption of improper practices during pre-cleaning and cleaning, can make it difficult to remove residues after each use, favoring the formation of biofilm. Widely isolated as contaminants of surgical instruments after use, Staphylococcus epidermidis are recognized for their ability to form biofilm on different surfaces. In this sense, the question is: how the manual and automated cleaning methods perform on the removal of S. epidermidis adhered to the surface of surgical instruments submitted to experimental contamination for different intervals? We aimed at comparing two leaning protocols, manual and automated, regarding their capacity for removing S. epidermidis from the surface of surgical instruments submitted to different intervals of contamination. This was an experimental research conducted at the Oral and Anaerobic Microbiology Laboratory, ICB/UFMG and at the UFMG microscopy center. Straight crile tweezers were selected to analyze areas with different challenges to the cleaning process: uneven (serrated and rack) and smooth (rod) surface. The specimens were contaminated by immersion in Triptical Soya Broth (TSB), containing 106 CFU/mL of a clinical sample of S. epidermidis. The bacterial adherence and the removal capacity of these microorganisms, submitted to manual or automated cleaning, were verified after one, two, four, six, eight, and 12 hours. Results were evaluated by microbiological culture and scanning electron microscopy (SEM). The results were analyzed using descriptive statistics and analysis of variance (ANOVA) techniques at a level of 5% confidence. In the group subjected to contamination, the bacterial load increased over time, ranging from 101­102 CFU/cm2 after one hour to 104 CFU/cm2 within 12 hours. Bacterial adhesion was observed after one hour, with the formation of biofilm after two hours, and, in general, an increase in the concentration of microorganisms at subsequent times. The microbial load was reduced by 1-2 log10 after manual cleaning and between 1-3 log10 after automated cleaning and was considered significant (p<0.05) in all fragments and times evaluated in the last group. SEM analysis showed the permanence of biofilm after using both methods. In general, rod fragments presented lower microbial load during the evaluation period in the different groups evaluated, and this difference (p<0.05) was significant at six hours. In conclusion, the S. epidermidis presented fast adherence capacity and biofilm formation after two hours of contact with the surgical instruments with bacterial load of 102 CFU/cm2. The automated cleaning was more effective than manual cleaning. However, neither method completely removed the biofilm formed. Pre-cleaning conditions, as well as the presence of difficult access areas, such as serration and rack, are critical factors in the processing quality of surgical instruments.

Stress conditions in the host induce persister cells and influence biofilm formation by Staphylococcus epidermidis RP62A

Abstract INTRODUCTION: Studies have demonstrated that pathogens react to the harsh conditions in human tissues by inducing mechanisms that promote survival. METHODS: Persistence and biofilm-forming ability were evaluated during stress conditions that mimic those in the host. RESULTS: Carbon-source availability had a positive effect on Staphylococcus epidermidis RP62A adhesion during hypoxia, accompanied by a decrease in pH. In contrast, iron limitation led to decreased surface-adherent biomass, accompanied by an increase medium acidification and lactate levels. Interestingly, iron starvation and hypoxia induced persister cells in planktonic culture. CONCLUSIONS: These findings highlight the role of host stress in the virulence of S. epidermidis.

Subchronic Oral Cadmium Exposure Exerts both Stimulatory and Suppressive Effects on Pulmonary Inflammation/Immune Reactivity in Rats / 生物医学与环境科学（英文）

OBJECTIVE@#The aim of this study is to investigate the effects of oral cadmium (Cd) ingestion on the pulmonary immune response.@*METHODS@#Determination of Cd content in lungs and histopathological evaluation of the tissue was performed in rats following 30-day oral Cd administration (5 and 50 mg/L). Antioxidant enzyme defense (superoxide dismutase and catalase), cell infiltration, and production of tumor necrosis factor (TNF) and interferon (IFN)-γ, as well as the activity of myeloperoxidase (MPO), nitric oxide (NO), and various cytokines [interleukin (IL)-1β, IL-6, IL-10, and IL-17] were investigated.@*RESULTS@#Cd caused tissue damage and cell infiltration in the lungs, and this damage was more pronounced at higher doses. Cd deposition resulted in lung inflammation characterized by a dose-dependent IL-1β increase in lung homogenates, increased TNF levels at both doses, and IL-6 stimulation at low doses with inhibition observed at higher doses. Cd exerted differential effects on lung leukocytes isolated by enzyme digestion, and these effects were characterized by a lack of change in the production of reactive oxygen and nitrogen species, an inhibition of IL-1β and TNF, and stimulation of MPO and IFN-γ. The higher capacity of Cd-exposed lung cells to respond to the opportunistic pathogen Staphylococcus epidermidis was demonstrated in vitro.@*CONCLUSION@#The potential of ingested Cd to exert both proinflammatory and immunosuppressive effects on pulmonary tissue inflammation and immune reactivity highlights the complex immunomodulatory actions of this metal.