Real-world study of ceftazidime-avibactam in the treatment of multidrug-resistant gram-negative bacterial infections / 中国临床药理学与治疗学

AIM: To describe and evaluate the clinical characteristics, treatment management and clinical outcomes of ceftazidime-avibactam (CZA) in the treatment of patients with multidrug-resistant gram-negative bacterial (MDR-GNB) infections. METHODS: A retrospective cohort study was performed on patients hospitalized in the Affiliated Hospital of Xuzhou Medical University from September 2019 to December 2021. Adult patients who received CZA for ≥ 72 hours consecutively were eligible for inclusion. The primary outcome was clinical failure, defined as a composite of 30-day all-cause mortality, microbiological failure and / or failure to resolve or improve signs and symptoms of infection during treatment with CZA. RESULTS: A total of 198 patients with MDR-GNB infections were described and evaluated, including 132 in the carbapenem-resistant Enterobatceriaceae (CRE) cohort and 66 in the Pseudomonas spp. cohort. The main infection sites were lung infection (92.42%), abdominal infection (10.61%), and intracranial infection (10.61%), among which 63 patients (31.82%) were positive for blood culture. Clinical failure, 30-day all-cause mortality and microbiological failure occurred in 61 (30.81%), 33(16.67%) and 11(5.56%) patients, respectively. Body mass index (BMI), acute physiology and chronic health evaluation scoring system (APACHE Ⅱ) and polymicrobial infections were positively associated with clinical outcome failureadjusted OR 1.109, 95%CI 1.017, 1.209; adjusted OR 1.071, 95%CI 1.015, 1.129; adjusted OR 2.844, 95%CI 1.391, 5.814, however, initiation of CZA within 48 hours of admission was protective (adjusted OR 0.424, 95%CI 0.205, 0.879). A total of 15 patients had adverse reactions possibly related to CZA, including 2 cases of rash, 6 cases of nausea and vomiting, and 7 cases of antibiotic-related diarrhea. CONCLUSION: CZA can be used to treat infections caused by a range of MDR-GNB, including Pseudomonas spp. and CRE.

Pseudomonas spp. and other psychrotrophic microorganisms in inspected and non-inspected Brazilian Minas Frescal cheese: proteolytic, lipolytic and AprX production potential / Pseudomonas spp. e outros micro-organismos psicrotróficos em queijos Minas Frescal inspecionados e não inspecionados: potencial proteolítico, lipolítico e produção de AprX

The most consumed cheese in Brazil, Minas Frescal cheese (MFC) is highly susceptible to microbial contamination and clandestine production and commercialization can pose a risk to consumer health. The storage of this fresh product under refrigeration, although more appropriate, may favor the growth of spoilage psychrotrophic bacteria. The objective of this study was to quantify and compare Pseudomonas spp. and other psychrotrophic bacteria in inspected and non-inspected MFC samples, evaluate their lipolytic and proteolytic activities and their metalloprotease production potentials. Twenty MFC samples were evaluated: 10 inspected and 10 non-inspected. Counts of psychrotrophic bacteria and Pseudomonas spp., evaluation of the proteolytic and lipolytic potential of the isolates, and identification of potential producers of alkaline metalloprotease (AprX) were assessed. The mean total psychrotrophic counts were 1.07 (±2.18) × 109CFU/g in the inspected samples and 4.5 (±5.86) × 108CFU/g in the non-inspected, with no significant difference (p=0.37). The average score of Pseudomonas spp. was 6.86 (±18.6) × 105 and 2.08 (±3.65) × 106 CFU/g for the inspected and non-inspected MFC samples, respectively, with no significant difference (p=0.1). Pseudomonas spp. represented 0.06% and 0.004% of psychrotrophic bacteria found in inspected and non-inspected MFC samples, respectively. Collectively, 694 psychrotrophic strains and 47Pseudomonas spp. were isolated, of which 59.9% and 68.1% were simultaneously proteolytic and lipolytic, respectively. Of the 470 psychrotrophs isolated from inspected and 224 from non-inspected cheese samples, 5.74% and 2.23% contained aprX, respectively, while 100 and 86.96% of the Pseudomonas spp. isolates in inspected and non-inspected cheese samples contained the gene. The production potential of AprX did not, however, determine the proteolytic activity on plates of these isolates under the conditions evaluated in this study. Of total, 65.63% of the psychrotrophs that contained aprX gene were confirmed as Pseudomonas spp., using genus-specific PCR. Phylogenetic analysis of the 16S rRNA gene of the other psychrotrophs that were potential producers of AprX identified them as Serratia spp. (n=7), Raoultella ornithinolytica (n=1), and Acinetobacter schindleri (n=1) in the inspected samples and Psychrobacter sanguinis (n=1) and Leuconostoc mesenteroides (n=1) in the non-inspected samples. The production conditions of Brazilian MFC of these samples, while meeting the legal determinations, are not sufficient to control Pseudomonas and other spoilage-related psychrotrophs. Thus, stricter hygienic measures are required during the formal production of this type of cheese.(AU)

O mais consumido no Brasil, o queijo Minas Frescal (QMF) é altamente suscetível à contaminação microbiana e a produção e comercialização clandestina podem representar um risco para a saúde do consumidor. O armazenamento deste produto fresco sob refrigeração, embora mais apropriado, pode favorecer a multiplicação de bactérias psicrotróficas deteriorantes. O objetivo deste estudo foi quantificar e comparar Pseudomonas spp. e outras bactérias psicrotróficas em amostras de QMF inspecionadas e não inspecionadas, avaliar o potencial lipolítico, proteolítico e de produção de metaloprotease alcalina. Vinte amostras de QMF foram avaliadas: 10 inspecionadas e 10 não inspecionadas. Foram avaliadas as contagens de bactérias psicrotróficas e Pseudomonas spp., o potencial proteolítico e lipolítico dos isolados e a identificação de potenciais produtores de metaloprotease alcalina (AprX). A média total das contagens de bactérias psicrotróficas foi de 1,07 (±2,18) × 109UFC/g nas amostras inspecionadas e 4,5 (±5,86) × 108UFC/g nas não inspecionadas, sem diferença significativa (p=0,37). A média de Pseudomonasspp. foi de 6,86 (±18,6) × 105 e 2,08 (±3,65) × 106UFC/g para as amostras QMF inspecionadas e não-inspecionadas, respectivamente, sem diferença significativa (p=0,1). Pseudomonas spp. representaram 0,06% e 0,004% de bactérias psicrotróficas encontradas em amostras QMF inspecionadas e não-inspecionadas, respectivamente. Das amostras inspecionadas e não inspecionadas, foram isoladas 694 colônias psicrotróficas e 47 Pseudomonasspp., dos quais 59,9% e 68,1% foram simultaneamente proteolíticos e lipolíticos, respectivamente. Dos 470 isolados de psicrotróficos das amostras de queijo inspecionados e dos 224 isolados das não inspecionadas, 5,74% e 2,23% continham o gene aprX, respectivamente, enquanto 100 e 86,96% das Pseudomonasspp. isoladas em amostras de queijo inspecionadas e não inspecionadas continham o potencial de expressão de AprX. Esse potencial, no entanto, não determinou a atividade proteolítica em placas desses isolados nas condições avaliadas neste estudo. Do total, 65,63% dos psicrotróficos que continham o gene aprX foram confirmados como Pseudomonasspp., utilizando PCR gênero-específico. A análise filogenética do gene 16S rRNA dos outros psicrotróficos que foram produtores potenciais de AprX os identificou como Serratia spp. (n=7), Raoultella ornithinolytica (n=1) e Acinetobacter schindleri (n=1) nas amostras inspecionadas e Psychrobacter sanguinis (n=1) e Leuconostoc mesenteroides (n=1) nas amostras não inspecionadas. As condições de produção do QMF dessas amostras, atendendo às determinações legais, não são suficientes para controlar a Pseudomonas e outros psicrotróficos relacionados à deterioração. Assim, medidas higiênicas mais rígidas são necessárias durante a produção formal deste tipo de queijo.(AU)

Screening of different Pseudomonas and Bacillus Spp. for production of L-glutamic acid and impact of their cell-free filtrate on growth and yield of brinjal (Solanum melongena)

Amino acids can play a different role in plants such as nitrogen source, hormonal precursor, and stress reducingagents. L-glutamic acid is involved in several plant metabolic processes. The objectives of present work were toevaluate the L-glutamic acid production by different agriculturally important Pseudomonas and Bacillus speciesand to determine the effects of L-glutamic acid containing cell-free filtrate on the growth and yield of brinjal. Anexperiment was conducted in a completely randomized block design. Out of eight different strains of Pseudomonas,the highest L glutamic acid was detected in Pseudomonas fluorescens 128 (1.397 g/l) followed by P. fluorescensNSPL07 (1.073 g/l) and Pseudomonas striata RCOF153 (0.563 g/l). Similarly, out of six different species ofBacillus, moderate L-glutamic acid was detected in Bacillus amyloliquefaciens MTCC10439. (0.232 g/l). Thegrowth stimulatory effects of L glutamic acid containing filtrate (200 ppm) were also studied and it was found that allgrowth parameters of brinjal (plant height, fruits per plant, fruit yield, etc.) improved significantly. Results indicatedthat bacterial secretion containing L-glutamic acid along with other amino acids has biostimulatory effects and itshould be used to enhance the plant growth and yield.

Prevalence of Non Fermenting Gram Negative Bacilli with Their in vitro Antibiotic Sensitivity Profile in RIMS, Ranchi

Background: Non fermenting Gram Negative Bacilli arediverse and complex group of bacteria that possess very fewdefined characteristics. They are aerobic, non-fermentingGram negative bacilli which were initially considered ascontaminants but have come up with life threatening infectionsin hospitals as multidrug resistant organisms posing a threatbecause of their inherent and acquired drug resistance nature.Aims: Isolation and identification of NFGNB in clinical samplesand determination of their antibiotic sensitivity profile.Materials and Methods: The study was conducted in theDepartment of Microbiology, RIMS, Ranchi from February2017-July 2017. Various clinical samples reaching theBacteriology section of the Department of Microbiology wereprocessed and NFGNB were isolated and identified usingstandard procedure and their antibiotic susceptibility wasperformed.Results: A total of 3581 samples were received out of which2246 were culture positive and 217 were identified as NFGNB.The isolation rate of NFGNB was 9.6%. Number of malesaffected by NFGNB was 121 and that of females was 96.Analysed by specimen NFGNB were isolated from 91 urine, 74pus, 11 ear swab, 6 sputum, 8 body fluid, 21 blood culture and6 catheter tip samples. Urine was most common specimenaccounting for 42% followed by pus (34%), blood (9%), earswab (5%), body fluid (4%), sputum and catheter tip (3%each).The clinical samples from indoor patients yielded highestpercentage of NFGNB (38%) followed by ICU patients (36%)and outdoor patients (26%). Among the NFGNB isolatedPseudomonaas aeruginosa (51%) was the most commonfollowed by Acinetobacter baumanii (22%), Pseudomonas spp(19%), Acinetobacter spp, Stenotrophomonas maltophila,Burkholderia cepacia (2% each), Ralstonia spp &Sphingobacterium spp (1%). Non fermenters were highlysensitive to Imipenem accounting for 91.5% followed byPiperacillin-tazobactam (71.5%), cefoperazone sulbactam(67.7%) & Amikacin (55.6%) on an average.Conclusion: NFGNB considered being contaminants in thepast have now emerged as important health care associatedinfections. In our setting Imipenem can be used for thepreliminary treatment of infections caused by nonfermenters.As these organisms are important opportunistic andnosocomial pathogens causing infections inimmunocompromised patients, better infection control policiesin our settings and its implementation is a must.

Endocarditis por Pseudomonas spp: Descripción de un caso poco frecuente / Endocarditis caused by Pseudomonas spp: description of a rare case

RESUMEN Las infecciones por los dispositivos cardiovasculares son cada vez más frecuentes. Se presenta el caso de un hombre de 62 años edad con fiebre y toma del estado general, que había sido intervenido hacía siete años para la implantación de un marcapasos. En los complementarios se observaron leucocitosis y hemoglobina por debajo de 10 g/L; y en el ecocardiograma, un electrodo de marcapaso en cavidades derechas con múltiples masas ecodensas que indicaban endocarditis infecciosa. Se realizó extracción quirúrgica del dispositivo y cultivo de muestras de las vegetaciones, con aislamiento de Pseudomonas spp. Se administró terapia antimicrobiana sobre la base del antibiograma y el paciente evolucionó satisfactoriamente. Se debe pensar en esta enfermedad ante todo paciente con marcapasos que presente fiebre y sintomatología general, una vez que se han descartado otros posibles focos de infección; además, se debe actuar rápido para lograr un tratamiento adecuado.

ABSTRACT Infections due to cardiovascular devices are becoming more frequent. Here is presented the case of a 62-year-old male patient with fever and poor general condition, who had been intervened seven years ago for the implantation of a pacemaker. In the blood tests, leukocytosis and hemoglobin below 10 g/L were observed. The echocardiogram showed a pacemaker electrode in the right cavities with multiple echo-dense masses indicating infectious endocarditis. A surgical extraction of the device was performed as well as culture of vegetation samples with the isolation of Pseudomonas spp. An antimicrobial therapy was provided on the basis of the antibiogram, and the patient progressed satisfactorily. This clinical entity should be considered in any patient with a pacemaker who presents fever and general symptoms, once other possible sources of infection are ruled out; in addition to acting quickly in order to achieve an adequate treatment.

Proteolytic and lipolytic potential of Pseudomonas spp. from goat and bovine raw milk / Potencial proteolítico e lipolítico de espécies de Pseudomonas do leite cru caprino e bovino

Pseudomonas, the main genus of gram-negative microorganisms isolated from milk, is psychrotrophic, biofilm-forming, and thermo-resistant deteriorating enzyme producers. The aim of this study was to quantify Pseudomonas spp. in goat's and cow's milk produced in the Paraná state, Brazil, to evaluate the deteriorating activity of the isolates at mesophilic and psychrotrophic conditions and to identify, at the species level, the isolates with alkaline metalloprotease (aprX gene) production potential. Microbiological, biochemical and molecular methods were used for isolating, confirming and identifying of isolates. The mean counts were 1.6 (±6.3)x104 and 0.89(±3)x102 CFU/mL for goat and bovine milk samples, respectively, immediately after milking. Of the Pseudomonas colonies isolated from goat milk (n=60), 91.7% showed proteolytic potential when incubated at 35°C/48 h and 80% at 7°C/10 days, and lipolytic potential was observed in 95% of the isolates incubated in mesophilic and 78.3% at refrigeration conditions. From the isolates of bovine milk (n=20), 35% showed proteolytic activity only when incubated at 35°C/48 h, and lipolytic potential was observed in 25% of the isolates incubated at 7°C/10d and 35°C/48h. It was observed that 83.3% and 25% of the isolates genetically confirmed as Pseudomonas spp. of goat and bovine milk showed the potential for alkaline metalloprotease production, with the species P. azotoformans, P. koreensis, P. gessardii, P. monteilii and P. lurida being the most frequent in goat milk and P. aeruginosa the only species identified in cow milk.(AU)

Pseudomonas é o principal gênero de micro-organismos Gram negativos isolados do leite, são psicrotróficos, formadores de biofilmes e produtores de enzimas deteriorantes termodúricas. O objetivo do presente trabalho foi quantificar Pseudomonas spp. no leite de cabras e vacas produzido no estado do Paraná, Brasil, avaliar a atividade deteriorante em temperatura mesofílica e psicrotrófica e identificar, em nível de espécie, os isolados com potencial de produção de metaloprotease alcalina (geneaprX). Foram utilizados métodos microbiológicos, bioquímicos e moleculares para isolamento, confirmação e identificação dos isolados. As contagens médias foram de 1,6 (±6,3) x 104 e 0,9 (±3) x 102 UFC/mL para as amostras de leite caprino e bovino, respectivamente. Dos isolados de Pseudomonas do leite de cabra (n=60), 91,7% demonstraram potencial proteolítico quando incubadas a 35°C/48h e 80% a 7°C/10dias e lipolíticos em 95% dos isolados incubados em mesofilia e em 78,3% dos incubados em temperatura de refrigeração. Dos isolados do leite bovino (n=20), foi verificada atividade proteolítica de 35% apenas quando incubadas a 35°C/48h e lipolítica em 25% dos isolados incubados a 7°C/10d e 35°C/48h. Foi observado que 83,3% e 25% dos isolados confirmados geneticamente como Pseudomonas spp. do leite caprino e bovino, respectivamente, apresentaram o potencial de produção de metaloprotease alcalina, sendo as espécies P. azotoformans, P. koreensis, P. gessardii, P. monteilii e P. lurida as mais frequentes no leite de cabras e P. aeruginosa a única identificada do leite de vacas.(AU)

Pseudomonas spp: contamination sources in bulk tanks of dairy farms / Pseudomonas spp: fontes de contaminação em tanques de expansão em fazendas leiteiras

This study focused on isolating Pseudomonas spp. during milking process in ten dairy farms with manual and mechanical milking systems during dry and rainy seasons, and evaluating DNA homology and patterns of distribution between isolates, in order to identify main sources of milk contamination by Pseudomonas spp. A total of 167 isolates of Pseudomonas spp. were obtained from water, milkers' hands, cows' teats, teat cups, cooling tanks and raw milk. Bacteria of Pseudomonas spp. genus were isolated from 85 and 82 sampling points in dairy farms with manual and mechanical milking system, respectively. A significant difference (p=0.02) on Pseudomonas spp. isolation was observed among samples of surface of cows' teats before and after pre-dipping, but no significant difference (p>0.05) was observed among milking systems or seasons. The possibility of the same Pseudomonas spp. patterns are distributed in different farms and seasons using Amplified Fragment Length Polymorphism (AFLP) technique was demonstrated. Milkers' hands, surface of cows' teats, teat cups and cooling tanks were associated with raw milk contamination with Pseudomonas spp. on farms with manual and mechanical milking system, showing that regardless of the type of milking system and season, proper hygiene procedures of equipment, utensils and workers' hands are essential to avoid contamination of the milk and, therefore, improve milk quality.(AU)

Este estudo se propôs a isolar Pseudomonas spp. durante o processo de ordenha em dez fazendas com sistemas manuais e mecanizados, durante as estações seca e chuvosa, além de avaliar a homologia do DNA e seus padrões de distribuição entre os isolados, a fim de se determinar as principais fontes de contaminação do leite. Cento e sessenta e sete isolados de Pseudomonas spp. foram obtidos a partir de amostras de água, mãos de ordenhadores, tetos, teteiras, tanques de resfriamento e leite cru armazenado, sendo 85 e 82 pontos de amostragem em fazendas com sistemas de ordenha manual e mecânico, respectivamente. Diferença estatisticamente significativa foi encontrada entre os isolados observados entre a superfície dos tetos antes e após o pré-dipping (p=0,02), mas nenhuma diferença foi encontrada entre sistemas de ordenha ou estações (p>0,05). A possibilidade do mesmo padrão de Pseudomonas spp. estar distribuído em diferentes fazendas ou estações foi avaliada pela técnica de Polimorfismo do Tamanho de Fragmento Amplificado (AFLP). As mãos de ordenhadores, superfície dos tetos das vacas, teteiras e tanques de resfriamento foram associados com a contaminação do leite cru, demonstrando que independente do tipo de ordenha e estação, a higiene adequada de equipamentos, utensílios e mãos dos ordenhadores é essencial para evitar contaminação do leite, e consequentemente aumentar sua qualidade.(AU)

Cultivable bacterial diversity of Paris polyphylla var. chinensis with 16 S rRNA sequence analysis / 中草药

Objective To analyze the bacterial diversity in stem rot and healthy plants of Paris polyphylla var. chinensis. Methods Bacterial strains were isolated from rhizomes, stems and leaves of the diseased and healthy plants of P. polyphylla var. chinensis using beef extract-peptone medium. Using 16 S rRNA universal primers 27F/1492R for PCR amplification, combined with DNA sequencing technology to preliminary identification the bacterial strains. Results The bacteria could be divided into 23 microbial species, belonging to 11 genera, isolated from healthy and diseased plants of P. polyphylla var. chinensis. Eleven endophytic bacteria, belonging to 4 genera were contained from healthy plants, in which there were 9, 10, and 5 species isolated from rhizomes, stems and leaves, respectively. Fourteen endophytic bacteria, belonging to 10 genera were contained from diseased plant, in which there were 11, 8, and 3 species isolated from rhizomes, stems, and leaves, respectively. The content of endophytic bacteria in rhizome of healthy plant was the highest, reached up to 2.999 × 105 cfu/g, while that in leaf was the lowest with 7.32 × 104 cfu/g. The quantities of Bacillus species in rhizome (73.3%), stem (67.1%), and leaf (81.8%) of healthy plant were the highest groups, Pseudomonas species in rhizome (35.6%), stem (50.3%) and leaf (60.5%) of diseased plants were the highest groups. Shannon-Wiener index and evenness index of healthy plant of P. polyphylla var. chinensis were higher than that of diseased plants. Conclusion The dominant group in the healthy plant of P. polyphylla var. chinensis was Bacillus, while the dominant groups in the diseased plant of P. polyphylla var. chinensis was Pseudomonas. The population diversity of the cultivable bacteria in healthy plant of P. polyphylla var. chinensis was more abundant than that of diseased plant.

Rhamnolipid Biosurfactants Produced by Pseudomonas Species

ABSTRACT: Surfactants are chemical products widely used in our daily life in toothpaste and other personal hygiene and cosmetic products, and in several industries. Biosurfactants are surfactants of biological origin that can be produced by microorganisms and have many advantages, such as low toxicity and high biodegradability, compared to synthetic counterparts. Unfortunately, high production costs limit the use of biosurfactants. Low-cost production is the most important factor for biosurfactants to be able to compete in the global market place. This review presents general information on rhamnolipid biosurfactant produced by Pseudomonas species, as well as on their production and applications. In addition, industrial products and their wastes used for rhamnolipid production are reviewed in detail based on recent studies.

Carbapenem Inactivation Method: Accurate Detection and Easy Interpretation of Carbapenemase Production in Enterobacteriaceae and Pseudomonas spp / 대한임상미생물학회지

BACKGROUND: We evaluated the carbapenem inactivation method (CIM) compared with the modified Hodge test (MHT) for the detection of carbapenemase-producing Gram-negative bacilli. METHODS: A total of 61 isolates of carbapenemase-producing Enterobacteriaceae (CPE: 14 KPC, 7 GES-5, 8 NDM-1, 9 VIM-2, 9 IMP-1, and 14 OXA-48-like), 34 isolates of metallo-β-lactamase (MBL)-producing Pseudomonas spp. (14 VIM-2 and 20 IMP-6), and 70 carbapenem-nonsusceptible carbapenemase-negative isolates were included. The CIM and MHT were performed for all of the isolates. To perform the CIM, a meropenem disk was incubated with a suspension of the isolate to be tested and then on Mueller-Hinton agar with the Escherichia coli ATCC 29522 strains. The absence of an inhibition zone indicates presence of a carbapenemase. The presence of a clearing zone indicates lack of a carbapenemase. RESULTS: The total sensitivity and specificity of CIM (96% sensitivity and 100% specificity) in carbapenem-nonsusceptible Enterobacteriaceae and Pseudomonas spp. were better than those of the MHT (77% sensitivity and 94% specificity). The interpretation of CIM results was easy, with no or 20 mm inhibition zones indicating negative carbapenemase activity. CONCLUSION: The CIM had excellent sensitivity and specificity for detection of CPE and MBL-producing Pseudomonas spp., and a positive result was easily determined, unlike the MHT.

Incorporação de antimicrobianos naturais em filme biodegradável à base de alginato para o controle de Listeria monocytogenes em embutido cárneo fatiado / Incorporation of natural antimicrobials into alginate based film for the control of Listeria monocytogenes in sliced meat product

A incorporação de substâncias antimicrobianas, entre elas os óleos essenciais, em embalagens tem como objetivo minimizar a contaminação microbiana em alimentos. No entanto, essa utilização é limitada por critérios sensoriais, sendo necessário determinar a concentração mínima necessária para inibir o desenvolvimento de micro-organismos sem afetar sensorialmente as características do alimento. Assim, os objetivos dessa pesquisa foram: determinar a concentração inibitória mínima (CIM) de óleos essenciais (OE) para Listeria monocytogenes (LM); avaliar do efeito da combinação de óleos essenciais para a redução da população de LM; avaliar a combinação de compostos ativos presentes em óleos essenciais para a inibição de LM, Pseudomonas spp e Salmonella spp; avaliar in vitro e in situ a eficiência antimicrobiana do filme à base de alginato incorporado de compostos ativos presentes em óleos essenciais; determinar a disponibilidade dos compostos ativos incorporados ao filme pela determinação dos compostos fenólicos totais; caracterizar o filme frente às propriedades mecânicas e propriedades de barreira, e verificar a aceitação pelo consumidor, através da análise sensorial, de fatias de salame embaladas com o filme antimicrobiano. Constatou-se que a combinação de eugenol (0,01%) e limoneno (0,04%) apresentou um maior efeito para a redução da população de LM comparado ao uso individual desses compostos, confirmando, portanto, a existência de sinergismo entre esses dois compostos. Em relação à Pseudomonas spp, o sinergismo foi constatado quando as concentrações de eugenol (0,15%) e de limoneno (0,30%) foram utilizadas, no entanto, para Salmonella spp o mesmo efeito não foi observado. Em ensaios in vitro apesar do aumento na concentração de eugenol e limoneno incorporados à matriz do filme, não houve diferença significativa para os valores de zona de inibição antimicrobiana porém, em ensaios in situ, a utilização desse filme como embalagem primária promoveu a redução de 2 log UFC/g da população de LM até o 10º dia de análise permanecendo constante até o 30º dia o que não ocorreu com a combinação de eugenol (0,15%) e limoneno (0,3%). A quantificação dos compostos fenólicos totais nas amostras mostrou que há correlação entre o teor de compostos fenólicos extraídos da amostra do filme e o comportamento de LM. As propriedades mecânicas e de barreira do filme à base de alginato não foram significativamente afetadas pelas concentrações de eugenol e limoneno avaliadas neste estudo. O sabor, o aroma e a aparência das amostras de salame foram aceitos pelos provadores mostrando que o uso do filme à base de alginato incorporado com eugenol e limoneno é viável para a aplicação como embalagem antimicrobiana para o controle de L. monocytogenes em salame fatiado. Este resultado é considerado importante, pois em alimentos com atividade de água e valores de pH adequados à multiplicação desse patógeno e armazenados sob refrigeração, a temperatura é capaz de selecionar a microbiota presente no alimento, favorecendo a multiplicação de micro-organismos psicrotróficos, como L. monocytogenes

The incorporation of antimicrobial substances in packages aims at reducing food microbial contamination among which the phenolic compounds extract from plants have received special attention being natural and attending consumer demand. However, the use of these compounds is limited by sensory criteria and it is necessary to determine the minimum concentration required to inhibit the growth of microorganisms without affecting the sensory characteristics of the food. The aim of this research were: to determine the minimum inhibitory concentration (MIC) of essential oils (EO) for Listeria monocytogenes (LM); to evaluate effect of the combination of essential oils in order to reduce LM population; to evaluate the active compounds combination for the inhibition of LM, Pseudomonas spp, and Salmonella spp; to evaluate the antimicrobial efficiency in vitro and in situ of the alginate film incorporated with the active compounds; to determine the availability of the active compounds incorporated into the film for the determination of total phenolic compounds; to characterize the mechanical and barrier properties of the film, and to verify consumer acceptance of slices of salami packaged with the antimicrobial film. The combination of eugenol (0.01%) and limonene (0.04%) showed a greater effect for reducing LM population compared to the individual use of these compounds, confirming the existence of synergism between these two compounds. Regarding Pseudomonas spp, synergism was observed when the concentrations of eugenol (0.15%) and limonene (0.30%) were used, however, the same effect was not observed for Salmonella spp. In in vitro tests, despite of the increase in the concentration of limonene and eugenol incorporated in the film matrix, no significant difference for the antimicrobial inhibition zone values was observed. In in situ tests, the film containing eugenol (0.3%) and limonene (0.6%) promoted the reduction of 2 log CFU/g of LM population in sliced salami, while the combination of eugenol (0.15%) and limonene (0.3%) did not have the same effect. The quantification of the phenolic compounds in the film samples showed that there is correlation between the content of phenolic compounds extracted from the film sample and LM behavior. The mechanical properties of the barrier film and the alginate were not significantly affected by eugenol, and limonene concentrations evaluated in this study. The taste, flavor and appearance of the salami samples were accepted by the panel showing that the use of the alginate-based film incorporated with limonene and eugenol are feasible for use as antimicrobial packaging for the control of L. monocytogenes in sliced salami. This is an important result, because in food matrix with water activity and pH suitable for the pathogen growth, the storage under refrigerated condition is able to select the psycrothophic microorganisms, such as L. monocytogenes

Prototipo de formulación y atmósfera de empaque para la cepa antagonista Pseudomonas fluorescens Ps006 / Formulation prototype and atmosphere packaging for the antagonistic strain Pseudomonas fluorescens PS006

El aislamiento Pseudomonas fluorescens Ps006 demostró alto potencial para ser usado como principio activo de un bioinsumo, por su capacidad para producir biosurfactantes, actividad solubilizadora de fósforo y antagonista ante diferentes fitopatógenos. Por tal razón, el presente trabajo tuvo como objetivos desarrollar y caracterizar un prototipo de formulación a base de P. fluorescens Ps006, estable bajo condiciones de almacenamiento. Inicialmente se caracterizó el principio activo y se seleccionaron los auxiliares de formulación compatibles con el mismo, evaluándose la estabilidad de su mezcla con tres soportes sólidos, a dos humedades diferentes (10% y 20%) durante tres meses de almacenamiento a temperaturas de 8, 18 y 28 ± 2 °C. El principio activo demostró actividad antagonista in vitro sobre cuatro fitopatógenos y la temperatura y la humedad afectaron su estabilidad durante el almacenamiento. A los prototipos de formulación más estables en cuanto a viabilidad y actividad biocontroladora se les evaluó su estabilidad en presencia y ausencia de oxígeno y de protectores de membrana. Se seleccionó el soporte S1 al 20% de humedad mezclado con el principio activo sin adición de protectores de membrana y almacenado en presencia de oxígeno, por ser el tratamiento más estable durante seis meses de alamacenamiento a tres temperaturas, con pérdidas de viabilidad inferiores al 5%.

The isolation Pseudomonas fluorescens PS006 demonstrated high potential to be used as an active ingredient of a bioprodut, because its capacity to produce biosurfactants, its phosphorus solubilizing activity and its antagonistic activity over different phytopathogens. For this reason, the present work had as objectives to develop and characterize a formulation prototype based on P. fluorescens PS006, stable under storage conditions. Initially the active ingredient was characterize and compatible formulation auxiliaries, were selected evaluating the stability of its mixture with three solid diluents at two different moistures (10% and 20 %) during three months of storage at temperatures of 8, 18 and 28 ± 2 °C. The active ingredient showed in vitro biocontrol activity over four phytopathogens and temperature and humidity affected its stability during storage. Stability of the most stable formulation prototypes in terms of viability and biocontrol activity was evaluated in presence and absence of oxygen and membrane protectors. Support S1 with 20% of moisture mixed with the active ingredient without addition of membrane protectors and stored in presence of oxygen, was selected as the most stable treatment during six months of storage at three temperatures, with viability losses lower than 5%.

Combined Use of the Modified Hodge Test and Carbapenemase Inhibition Test for Detection of Carbapenemase-Producing Enterobacteriaceae and Metallo-beta-Lactamase-Producing Pseudomonas spp

BACKGROUND: We evaluated the combined use of the modified Hodge test (MHT) and carbapenemase inhibition test (CIT) using phenylboronic acid (PBA) and EDTA to detect carbapenemase-producing Enterobacteriaceae (CPE) and metallo-beta-lactamase (MBL)-producing Pseudomonas spp. METHODS: A total of 49 isolates of CPE (15 Klebsiella pneumoniae carbapenemase [KPC], 5 Guiana extended-spectrum beta-lactamase [GES]-5, 9 New Delhi metallo-beta-lactamase [NDM]-1, 5 Verona integron-encoded metallo-beta-lactamase [VIM]-2, 3 imipenem-hydrolyzing beta-lactamase [IMP], and 12 oxacillinase [OXA]-48-like), 25 isolates of MBL-producing Pseudomonas spp. (14 VIM-2 and 11 IMP), and 35 carbapenemase-negative controls were included. The MHT was performed for all isolates as recommended by the Clinical and Laboratory Standards Institute. Enhanced growth of the indicator strain was measured in mm with a ruler. The CIT was performed by directly dripping PBA and EDTA solutions onto carbapenem disks that were placed on Mueller-Hinton agar plates seeded with the test strain. RESULTS: Considering the results of the MHT with the ertapenem disk in Enterobacteriaceae and Pseudomonas spp., the CIT with the meropenem disk in Enterobacteriaceae, and the imipenem disk in Pseudomonas spp., three combined disk tests, namely MHT-positive plus PBA-positive, EDTA-positive, and MHT-positive plus PBA-negative plus EDTA-negative, had excellent sensitivity and specificity for the detection of KPC- (100% sensitivity and 100% specificity), MBL- (94% sensitivity and 100% specificity), and OXA-48-like-producing isolates (100% sensitivity and 100% specificity), respectively. CONCLUSIONS: Combined use of the MHT and CIT with PBA and EDTA, for the detection of CPE and MBL-producing Pseudomonas spp., is effective in detecting and characterizing carbapenemases in routine laboratories.

Aerobacterias en las unidades de cuidado intensivo del Hospital Universitario Fernando Troconis, Colombia / Air bacteria existing in the intensive care units of Fernando Troconis university hospital in Colombia

Introducción: las infecciones nosocomiales se consideran un importante problema de salud. Los agentes patógenos frecuentemente responsables de estas infecciones son Pseudomonas spp. y Staphylococcus spp., patógenos que pueden estar presente en los bioaerosoles en hospitales. Objetivo: valorar la presencia de aerobacterias en las unidades de cuidado intensivo del Hospital Universitario Fernando Troconis, Colombia. Métodos: se recolectaron muestras de aire por triplicado en las dos estaciones de monitoreo ubicadas en las unidades de cuidados intensivos para adultos, pediátrica y neonatal, respectivamente. Se empleó para ello un impactador de cascada provisto con agar manitol salado para la recolección de aerobacterias Staphylococcus spp. y agar pseudomona para Pseudomonas spp. Las muestras recolectadas se incubaron a 37 °C durante 48 horas. Se aplicó análisis de varianza jerarquizado para determinar la influencia del género, estación y unidad sobre la concentración de aerobacterias. Resultados: la máxima concentración obtenida fue 979,9 ± 31,3 UFC/m³ y el máximo valor promedio 277 ± 59,2 UFC/m³. La concentración de Staphylococcus spp. sobrepasó a la de Pseudomonas spp. La unidad con mayor concentración de aerobacterias fue la de adulto, seguida por la neonatal y pediátrica. Los aerosoles respirables representaron el 65 por ciento en relación con los aerosoles sedimentables y se registraron mayores concentraciones de aerobacterias respirables Staphylococcus spp. (71,5 por ciento) comparadas con Pseudomonas spp. (64,6 por ciento). Conclusiones: la concentración de aerobacterias en las unidades de cuidados intensivos es alta, con un alto porcentaje de aerosoles respirables, lo que incrementa la probabilidad de que los pacientes asistidos contraigan infecciones nosocomiales por aerobacterias(AU)

Introduction: nosocomial infections are considered to be significant health problems. The most frequent pathogenic agents responsible for this are Pseudomonas spp. and Staphylococcus spp which can be present in bioaerosols in hospitals. Objective: to assess the presence of airborne bacteria in intensive care unit of Fernando Troconis university hospital in Colombia. Methods: samples were collected in triplicate at the two monitoring stations located in each of the three intensive care units of the hospital (adult, pediatric and neonatal), using cascade impactor with selective agars: mannitol salt for Staphylococcus spp. and pseudomona agar for Pseudomonas spp. The collected samples were incubated at 37 °C for 48 hours. A hierarchical variance analysis was applied to determine the influence of factors such as gender, monitoring station and unit on the concentration of airborne bacteria concentration. Results: the highest concentration was 979.9 ± 31.3 CFU/m3 and the maximum average value was 277 ± 59.2 CFU/m3. Staphylococcus spp. concentration exceeded that of Pseudomonas spp. The intensive care unit with the highest concentration was the adult one, followed by the neonatal and the pediatric ones. Breathable aerosols accounted for 65 percent compared with settleable aerosols, and higher concentration of breathable Staphylococcus spp. airborne bacteria (71.5 percent) compared with Pseudomonas spp. (64.6 percent). Conclusions: airborne bacteria concentration in the intensive care units was high, with significant percentage of breathable aerosols. All this increases the probabilities for the assisted patients to catch nosocomial infections caused by airborne bacteria(AU)

Analysis of the genetic context of high level aminoglycosides resistance gene 16S rRNA methylase gene armA / 国际检验医学杂志

Objective To analysis the genetic context of armA gene identified in different species .Methods BLASTN searches were used to analysis sequences harboring armA submitted to the GenBank database .Results armA gene was mostly found down-stream of ISCR1 element and was most commonly detected in Enterobacter spp ..Its flanking sequences were highly conserved in Enterobacter spp ..Conclusion The genetic context of armA gene reported in different species scattered in different geometrical lo-cations share some common characteristics .

Prevalence of metallo-β-lactamase producing pseudomonas spp.(in Tertiary Care Hospital).

Background: Metallo-β-lactamase (MBL) mediated resistance to carbapenem is an emerging threat in Pseudomonas isolates. The aim of this study is to detect metallo-β-lactamase producing isolates of Pseudomonas spp. from various clinical samples from indoor patients in a teaching hospital. Materials and Methods: Total 900 bacterial strains were isolated from different clinical samples from indoor patients. The bacterial strains were isolated and identified as per the standard guidelines. Amongst them 100 isolates of Pseudomonas were taken for the present study. All pseudomonas isolates were subjected to antimicrobial susceptibility testing by Kirby-Bauer disc diffusion method (CLSIs). In all imipenem resistant isolates of Pseudomonas spp., MBL detection was carried out by Imipenem-EDTA combined-disc synergy test (CDST). Results: Out of 100 isolates of Pseudomonas, 44 (44%) were imipenem resistant. Of these 44 isolates, 30 were producing MBL enzyme. 30 MBL positive isolate included 12 (40%) from surgical wards, 10 (33.33%) from tuberculosis ward, 4 (13%) from medicine ward, 2 (7%) from paediatric ward, 1 (3%) from urology ward and 1 (3%) from neonatal ICU. All MBL positive strains were resistant to β-lactams, aminoglycosides and fluoroquinolones. Conclusion: Prevalence of MBL producing Pseudomonas spp. is 30%. The MBL producing Pseudomonas spp. isolates were multidrug resistant. It is important to identify MBL producing pseudomonas isolates in laboratory as may cause serious infections and may cause a nosocomial outbreak.

Paper currencies, a potential carrier of pathogenic microorganisms.

Microbial analysis of 500 Indian currencies collected from people of different categories across the state Assam (India) has shown the presence of various pathogenic microorganisms viz, E. coli, Pseudomonas spp., Klebsiella spp., Streptococcus spp. and Staphylococcus sp. which are known to be responsible for watery diarrhea, mouth skin diseases, pneumonia, respiratory track diseases, gastro intestinal diseases etc. This may be due to the climatic conditions of most of the third world Asian countries which favors the optimum growth conditions for the microorganisms and a huge number of carriers handling them due to larger population in these regions.

Opportunistic microorganisms in patients undergoing antibiotic therapy for pulmonary tuberculosis

Antimicrobial therapy may cause changes in the resident oral microbiota, with the increase of opportunistic pathogens. The aim of this study was to compare the prevalence of Candida, Staphylococcus, Pseudomonas and Enterobacteriaceae in the oral cavity of fifty patients undergoing antibiotic therapy for pulmonary tuberculosis and systemically healthy controls. Oral rinsing and subgingival samples were obtained, plated in Sabouraud dextrose agar with chloramphenicol, mannitol agar and MacConkey agar, and incubated for 48 h at 37ºC. Candida spp. and coagulase-positive staphylococci were identified by phenotypic tests, C. dubliniensis, by multiplex PCR, and coagulase-negative staphylococci, Enterobacteriaceae and Pseudomonas spp., by the API systems. The number of Candida spp. was significantly higher in tuberculosis patients, and C. albicans was the most prevalent specie. No significant differences in the prevalence of other microorganisms were observed. In conclusion, the antimicrobial therapy for pulmonary tuberculosis induced significant increase only in the amounts of Candida spp.

Biosurfactant production in sugar beet molasses by some Pseudomonas spp.

In this study, rhamnolipid biosurfactant production was investigated in eighteen strains of Pseudomonas spp.. Rhamnolipid by these strains was determined by a spectrophotometric method in nutrient broth medium (NB). From the 18 strains screened, two Pseudomonas strains (Pseudomonas luteola B17 and Pseudomonas putida B12) which had produced the highest percentage yield of rhamnolipid were examined for rhamnolipid production at different incubation times (24, 48 and 72 hr) and different sugar beet molasses concentrations [1-5 % w/v concentration (1-5 g molasses/100 ml water)]. The rhamnolipid production increased with the increase in the concentration of molasses and maximum production occurred when 5 % (w/v) of molasses were used. At the same time, maximum rhamnolipid production occurred after 72 hr of incubation. When the amount of rhamnolipid produced at different incubation times (24, 48 and 72 hr) and with different concentrations of molasses [1-5 % w/v concentration (1-5 g molasses/100 ml water)] by Pseudomonas spp.; was compared, no significant difference in amount of production was seen. These studies show that the waste product from sugar industry may be suggested for important biotechnological processes such as rhamnolipid production.

Investigação de Salmonella spp., Listeria spp., Campylobacter spp. e Pseudomonas spp. no trato intestinal de avestruzes (Struthio camelus) criados no estado do Rio de Janeiro, Brasil / Investigation of Salmonella spp., Listeria spp., Campylobacter spp. and Pseudomonas spp. in ostriches (Struthio camelus) intestine from Rio de Janeiro State, Brazil

Na estrutiocultura, pesquisas relacionadas com a prevalência de micro-organismos patogênicos para esses animais e de importância em saúde pública ainda são escassas. O objetivo deste trabalho foi investigar a presença de Salmonella spp., Listeria spp., Campylobacter spp. e Pseudomonas spp. a partir de 60 amostras de suabes cloacais, provenientes de quatro criatórios de avestruzes e avaliar o perfil de susceptibilidade destes micro-organismos frente aos antimicrobianos. Os micro-organismos dos gêneros Salmonella, Listeria e Campylobacter não foram encontrados nas amostras analisadas. Pseudomonas aeruginosa foi isolado a partir de 17 amostras (28,3,%), provenientes de animais de diferentes faixas etárias, oriundos dos quatro criatórios investigados. Adicionalmente, Escherichia coli foi isolado de 57 amostras (95%), Klebsiella spp., de cinco amostras (8,33%), Proteus mirabilis, Proteus vulgaris e Enterobacter spp. de uma amostra (1,66%). Das 17 cepas de P. aeruginosa submetidas ao teste de susceptibilidade aos antimicrobianos, todas (100%) apresentaram sensibilidade à Amicacina e à Ciprofloxacina e todas (100%) foram resistentes ao Sulfametoxazol/Trimetoprim e à Tetraciclina. Foram encontrados cinco perfis diferentes de resistência aos antimicrobianos, indicando uma variação da resistência entre as cepas de Pseudomonas isoladas, inclusive em animais do mesmo criatório e mantidos no mesmo piquete.

There has been limited research on the prevalence of ostrich intestinal pathogens and on the role of these animals as foodborne pathogens source. This study was conducted to estimate the frequence of Salmonella spp., Listeria spp., Campylobacter spp. and Pseudomonas spp. from intestinal swabs of ostriches and to investigate the antibiotic resistance of the isolates. Sixty samples collected from four ostrich farms were examined. Salmonella, Listeria and Campylobacter were not isolated from the samples investigated and Pseudomonas aeruginosa was isolated from 17 (28.3%) samples. Additionally, Escherichia coli was isolated from 57 samples, (95%), Klebsiella spp. from five (8.33%), and Proteus mirabilis, Proteus vulgaris and Enterobacter spp. from one sample (1,66%). All Pseudomonas isolates were susceptible to Amicacin and Ciprofloxacin, and all of them (100%) were resistant to Trimethoprin/Sulfametox and to Tetracicline. Five antimicrobial resistance profiles were found, showing a resistance diversity among the Pseudomonas isolates, even in the same farm and raised at the same pen.