Role of LC3-associated phagocytosis in regulating infection / 中华微生物学和免疫学杂志

LC3-associated phagocytosis (LAP) is a special phagocytosis occurring at the intersection of the two pathways of phagocytosis and autophagy. A hallmark event of the LAP process is the recruitment of microtubule-associated proteinⅠlight chain type 3-Ⅱ(LC3Ⅱ) to the phagosome surface of the monolayer membrane structure. The LAP pathway relies on the functions of the RUN domain and cysteine-rich domain containing, Beclin 1-interacting protein (Rubicon) and reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. The LC3-associated phagosome (LAPosome) binds to the lysosome to digest and degrade the contents. In recent years, increasing studies have found that LAP plays an important role in the infections caused by pathogenic microorganisms including fungi and bacteria. LAP is a crucial way in the host to resist and degrade the infection of pathogenic microorganisms. However, some pathogenic microorganisms can effectively escape from LAP in the host and even use LAPosome as a place for colonization and replication. This article summarized the recent progress in the role of LAP in host defense against pathogenic microorganism infection and the significance of it in the occurrence and development of diseases.

Infecciones urinarias y su relación con catéter vesical en pacientes ingresados

RESUMEN Introducción: las infecciones urinarias intrahospitalarias son una problemática desde las perspectivas clínica, epidemiológica y terapéutica. El 70 % se presentan en pacientes cateterizados, y generan un importante impacto sobre la morbimortalidad, y costos asociados al proceso de atención. Objetivo: determinar los microorganismos que incidieron en la infección urinaria de los pacientes ingresados y relacionar la misma con catéter vesical. Materiales y métodos: se realizó un estudio observacional, descriptivo y retrospectivo. Los casos correspondieron a 171 muestras de orina que se recibieron en el laboratorio de Microbiología del Hospital Clínico Quirúrgico Interprovincial Ambrosio Grillo, de Santiago de Cuba, entre enero y septiembre de 2019, obtenidas de los pacientes cateterizados ingresados en dicho centro asistencial, con diagnóstico de infección urinaria. Resultados: predominaron los pacientes del sexo femenino con más de 65 años de edad. El patógeno más aislado en los cultivos de orina fue Escherichia coli; el parcial de orina tuvo un ligero aumento en la sensibilidad; con relación a los urocultivos de los pacientes con infección urinaria, hubo un 34,5 % de estos con catéter vesical por más de siete días. Conclusiones: la utilización de dispositivos invasivos es un factor de riesgo significativo en el desarrollo de infección urinaria intrahospitalaria.

ABSTRACT Introduction: intra-hospital urinary infections are a problem from the clinical, epidemiological and therapeutic perspectives. 70 % are present in catheterized patients, and generate an important impact on morbidity and mortality, and on the costs associated with the care process. Objective: to determine the microorganisms that impacted on the urinary infection of the hospitalized patients and to relate it to vesical catheter. Materials and methods: an observational, descriptive and retrospective study was carried out. The cases corresponded to 171 urine samples that were received at the Microbiology laboratory of the Interprovincial Clinical Surgical Hospital Ambrosio Grillo, of Santiago de Cuba, between January and September 2019, obtained from catheterized patients admitted to that care facility with diagnosis of urinary infection. Results: female patients over 65 years old predominated. The most isolated pathogen in urine cultures was Escherichia coli; urine partial had a slight increase in sensitivity; in relation to urocultures of patients with urinary infection, 34.5 % of them had vesical catheter for more than seven days. Conclusions: the use of invasive devices is a significant risk factor in the development of intra-hospital urine infection.

Application of digital PCR technology in the precise molecular diagnosis: opportunities and challenges / 中华检验医学杂志

Digital polymerase chain reaction (dPCR) is an absolute quantitative technique that has been rapidly developed in recent years. This technique assigns the reaction system containing DNA template to a large number of independent reaction units for PCR, and calculates the DNA copy number according to the Poisson distribution and statistical positive signals. In contrast to conventional qPCR, dPCR does not depend on amplification curves, is not affected by amplification efficiency, thus has high accuracy and repeatability, and can achieve the absolute quantification. This article reviews the development history of dPCR and its application in molecular diagnosis, tumor liquid biopsy and prenatal diagnosis of infectious diseases, and looks forward to the application prospect of this technology.

Distribution and drug resistance of wound pathogenic microorganisms in outpatients of wound healing center / 中华创伤杂志

Objective:To analyze the distribution and drug resistance of wound pathogenic microorganisms in outpatients of wound healing center so as to provide a basis for the standardized construction of wound healing centers.Methods:A retrospective case series study was used to analyzed the data of 365 outpatients treated at Ruijin Hospital, Shanghai Jiaotong University School of Medicine from December 2017 to October 2019. There were 220 males and 145 females, aged (58.8±18.9)years (range, 18-98 years). The patients included 92 first-visit patients and 273 re-visit patients. The culture results (positive rate of pathogenic microorganisms, bacterial species, bacterial distribution) and drug sensitivity results of the wound secretions were compared and analyzed.Results:(1) Among 365 samples of wound secretions, 198 patients were positive for pathogenic microorganisms with a positive rate of 54.3%. A total of 107 strains (51.0%) of Gram-positive bacteria were detected, mainly Staphylococcus aureus (70 strains, 33.3%); 95 strains (45.2%) of Gram-negative bacteria were detected, mainly Escherichia coli (20 strains, 9.5%), followed by Pseudomonas aeruginosa (17 strains, 8.1%); 8 strains (3.8%) of fungi were detected. (2) A total of 26 (28.3%) first-visit patients were positive for pathogenic microorganisms, and 172 (63.0%) re-visit patients were positive for pathogenic microorganisms. The rate of positive microorganism detection had significant differences between first-visit and re-visit patients ( P<0.05). (3) A total of 29 strains were detected in first-visit patients, including 16 strains (55.2%) of Gram-positive bacteria, 11 strains (37.9%) of Gram-negative bacteria and 2 strains (6.9%) of fungi. A total of 181 strains were detected in re-visit patients, including 91 strains (50.3%) of Gram-positive bacteria, 84 strains (46.4%) of Gram-negative bacteria and 6 strains (3.3%) of fungi. The microbial distribution was significantly different between first-visit and re-visit patients ( P<0.05). (4) Compared with first-visit patients, the resistance of Staphylococcus aureus isolated from the re-visit patients to spenicillin, oxacillin, ciprofloxacin, tetracycline, clindamycin, moxifloxacin, erythromycin, and levofloxacin were increased variably. No vancomycin-resistant Staphylococcus aureus was detected, indicating that the staphylococcus aureus presented in the wound was highly sensitive to vancomycin. Conclusions:Staphylococcus aureus is the most common microorganism in wound secretions in outpatients of wound healing center. The rate of positive pathogenic microorganisms in wound secretions of re-visit patients is significantly higher than that of first-visit patients, and the distribution of pathogenic microorganisms of first-visited and revisited patients differs significantly. The Staphylococcus aureus detected in re-visit patients has a higher resistance to common antibiotics compared with first-visit patients. It is suggested that timely detection of pathogenic microorganisms in outpatients and effective control and supervision of outpatient infections are important contents that cannot be ignored in the construction of wound healing center.

Biosafety risk assessment based on the perspective of public health / 上海预防医学

Objective:To assess the biosafety risk from a public health perspective and provide scientific evidence for centers for disease control and prevention to formulate diversified strategies and well-organized resource allocation. Methods:Based on the global summary of pathogenic microorganism which might be used against human beings intentionally， we performed a multi-round consultation to the expert team with a scientific background and professional qualification， using a Delphi method. According to the consultation and reliability test， a consistent evaluation was conducted from seven dimensions， including fatality rate， implementation of biosafety-related events， short-term probability， long-term probability， difficulty of rescue， early detection， and response capacity of the public health system. Results:The overall opinions of the experts tended to be consistent. Bacillus anthracis had been scored the highest in the comprehensive biosafety risk， which was much higher than the second （botulinum toxin） and third places （Yersinia pestis）， raising a significant public health concern. In addition， multiple hemorrhagic fever viruses had a higher biosafety risk. Conclusions:Based on the perspective of public health， the biosafety risk can be evaluated reasonably. Pathogenic microorganisms with zoonotic characteristics and long incubation periods are more difficult to detect in advance in the environment， posing a higher risk. The formulation of disease control and prevention strategies in public health resource-limited areas warrants particular attention to high-risk biosafety events.

Analysis of bacterial detection in children with acute lung injury (respiratory distress syndrome) / 公共卫生与预防医学

Objective To investigate the distribution of pathogenic bacteria and the results of drug sensitivity test in children with acute lung injury (respiratory distress syndrome), so as to guide rational clinical drug use. Methods A total of 254 cases of children diagnosed with acute lung injury (respiratory distress syndrome) in Wuhan Children's Hospital from May 2017 to May 2019 were retrospectively analyzed. Sputum samples were collected from all children for pathogenic microorganisms detection and drug sensitivity test. Results Of 127 strains of pathogenic bacteria were isolated from 254 children. Gram-negative bacilli were the main pathogenic bacteria, among which 38 strains of acinetobacter baumannii were infected, accounting for 29.92%, and 13 strains of pseudomonas aeruginosa were infected, accounting for 10.23%. There were 10 strains of stenotrophomonas maltophilia (7.87%) and 42 strains of fungal infection (33.07%). There were 26 cases of mixed infection, of which 16 cases were infected with acinetobacter baumannii and candida albicans, accounting for 61.54%. Acinetobacter baumannii was resistant to a variety of antibacterial drugs and had a sensitivity of >50% to imipenem. Conclusion Gram-negative bacilli were the main pathogenic bacteria in children with acute lung injury (respiratory distress syndrome). Given that acinetobacter baumannii with the highest infection rate is resistant to various drugs, it is necessary to dynamically detect the resistance of pathogenic bacteria and reasonably choose antimicrobial agents for treatment.

Métodos de identificación polifásica aplicados a la búsqueda de microorganismos con potencial industrial / Polyphasic identification methods applied in searching for microorganisms with industrial potential

Introducción: La bioprospección de metabolitos de interés antropogénico emplea métodos de recolección de microorganismos en ecosistemas extremófilos o endémicos. La microbiota aislada en estos lugares puede o no incluir microorganismos patógenos. Es imprescindible un enfoque interdisciplinario que permita abordar la búsqueda de las especies de interés mientras se preserva la buena salud de los investigadores. Objetivo: Identificar molecular, bioquímica y morfológicamente microorganismos patógenos humanos en cepas celulolíticas de importancia industrial almacenadas en el banco de cepas del Laboratorio de Investigación de la Facultad de Ingeniería Química de la Universidad Central del Ecuador, procedentes del Yasuní, la Antártida y Balzapamba. Métodos: Se realizó un estudio de bioprospección de bacterias celulolíticas empleando técnicas de microbiología ambiental. Se evaluaron las características morfológicas mediante tinciones, como por ejemplo Gram. Además, se realizaron pruebas bioquímicas y antibiogramas para bacterias Gram-negativas y Gram-positivas. Las pruebas moleculares utilizaron extracción de ADN bacteriano para la secuenciación Sanger del gen 16S. Resultados: Se encontraron las especies Klebsiella pneumoniae (Y2 y Y3r) y Nocardia asteroides (Y1 y Y3p) en las muestras de material lignocelulósico recolectadas en Yasuní, mientras que las especies aisladas en la Antártida y en Balzapamba corresponden a Bacillus subtillis. Conclusiones: Se identificaron cepas pertenecientes a diferentes géneros bacterianos. Las bacterias del género Klebsiella, en las muestras colectadas en Yasuní, podrían tener un potencial patógeno. Eso se puede corroborar con técnicas de genotipificación. Por lo tanto, puede existir riesgo para los seres humanos que realizan bioprospección en ese ecosistema y se deben tomar medidas de bioseguridad.

Abstract Background: The bioprospection of metabolites of anthropogenic interests employs methods of collecting microorganisms in extremophile or endemic ecosystems. The microbiota isolated in these places may or may not include pathogenic microorganisms. Therefore, an interdisciplinary approach is essential to address the search of the species of interest while the good health of the researchers is preserved. Objective: To identify in molecular, biochemical and morphologically ways some human pathogenic microorganisms in cellulolytic strains of industrial importance stored in the strain bank of the Research Laboratory of the Faculty of Chemical Engineering at the Central University of Ecuador, from Yasuní, Antarctic and Balzapamba. Methods: IA bioprospecting study of cellulolytic bacteria was performed using environmental microbiology techniques. Morphological characteristics were assessed by Gram staining. In addition, biochemical tests and antibiograms were performed for Gram-negative and Gram-positive bacteria. The molecular tests used extraction of bacterial ADN for 16S gene Sanger sequencing. Results: The species Klebsiella pneumoniae (Y2 and Y3r) and Nocardia asteroides (Y1 and Y3p) were found in samples of lignocellulosic material collected in Yasuni, while the isolated species in Antarctica and Balzapamba correspond to Bacillus subtillis. Conclusions: Strains belonging to different bacterial genera were identified. The bacteria of the genus Klebsiella from the samples collected in Yasuní could have a potential pathogen. This can be corroborated with genotyping techniques. Therefore, there could be a risk to humans who perform bioprospecting in that ecosystem and biosecurity measures should be taken.

Listeria monocytogenes in ham sliced in supermarkets in Recife city, Pernambuco state / Listeria monocytogenes em presuntos fatiados em supermercados da cidade de Recife, Pernambuco

The aim of this study was to investigate Listeria monocytogenes in ham sliced in supermarkets in Recife city, Pernambuco state. In total, 40 samples of sliced ham were collected, and 25 g of ham was added to 225 mL of Demi Fraser broth. After incubation, 0.1 mL was inoculated in Fraser broth and, subsequently, sown in supplemented Listeria Selective Agar, based on Otaviani and Agosti. The following tests were carried out for confirmation purposes: Gram stain, motility test, catalase test and cAMP test. There was L. monocytogenes in 25% (10/40) of the samples. The presence of L. monocytogenes in ready-to-eat food, such as sliced ham, is likely related to lack of proper equipment-cleaning in supermarkets, a fact that poses great risk to public health.(AU)

Objetivou-se com esse estudo realizar a pesquisa de Listeria monocytogenes em presuntos fatiados em supermercados da cidade de Recife, Pernambuco. Foram adquiridas 40 amostras de presuntos fatiados. Para o isolamento, foram utilizados 25 g do alimento para 225 mL do caldo Demi Fraser, após incubação, inoculou-se 0,1mL em caldo Fraser e posteriormente realizou-se a semeadura em Agar seletivo suplementado para Listeria de acordo com Otaviani e Agosti. Como testes confirmatórios, foram realizados a coloração de Gram, teste de motilidade, teste da catalase e teste de cAMP. Identificou-se a presença de L. monocytogenes em 25% (10/40) das amostras. A presença da L. monocytogenes em alimentos prontos para consumo, como o presunto fatiado, é de grande risco à saúde pública e pode estar relacionada à ocorrência de falhas na higienização dos equipamentos nos supermercados.(AU)

Application of Raman spectroscopy in the rapid detection of pathogenic microorganisms / 中华检验医学杂志

With the rapid development of instrument technology , Raman spectrometer has become one of the fastest growing type of instrument in the molecular spectroscopy . In recent years , Raman spectrometer gradually emerging in the application in the domain of biology and medicine , Raman spectroscopy technology appears new development constantly in the rapid identification and classification of microorganisms because of its rapid , efficient, sensitive, noninvasive, repeatability and other unique advantages.This article describes its application in the rapid detection of bacteria , viruses and other microorganisms , and also prospects for the application of Raman spectroscopy in future clinical work .

Effects of sugarcane juice addition on the population dynamics of Escherichia coli and the presence of Shiga-toxigenic E. coli during the anaerobic codigestion of dairy cattle manure / Efeito da adição de caldo de cana-de-açúcar na dinâmica da população de Escherichia coli e presença de E. coli shigatoxigênicas durante a codigestão anaeróbia de dejetos bovinos leiteiros

ABSTRACT: The objective of this study was to evaluate the effects of the addition of sugarcane juice on the population dynamics of Escherichia coli and the presence of Shiga-toxigenic E. coli (STEC) during the anaerobic codigestion of dairy cattle manure. For the overall analyses at the end of a hydraulic retention time of 90 days, ten two-liter batch-type biodigesters were divided into two treatment groups: biodigester containing manure and water (MW) and the biodigester containing manure, water and sugarcane juice (MSC). For monitoring the population dynamics and presence of microorganisms, pH, and volatile acidity, tests were carried out every ten days, on 36 smaller-scale batch biodigesters made of one-liter plastic bottles (18 for each treatment). The reductions in E. coli population over time were significant in the MW (60 days) and MSC (20 days) biodigesters. Inactivation of STEC occurred in a shorter period (40 days in MW and <10 days in MSC). Significant differences were obtained between the two treatments, with the pH values being lower, the concentrations of volatile acids (VA) being higher, and the inactivation of E. coli and STEC being faster in the biodigester with sugarcane juice added. The amount of sugarcane juice applied (7%) suggests its suitability for the sanitization of dairy cattle manure for use as a biofertilizer, given the high reduction in the E. coli population and inactivation of STEC.

RESUMO: O estudo teve como objetivo avaliar o efeito da adição de caldo de cana-de-açúcar sobre a dinâmica da população de Escherichia coli e presença de E. coli shigatogixênicas (STEC) no processo de codigestão anaeróbia de dejetos de bovinos leiteiros. Foram utilizados dez biodigestores bateladas divididos em dois tratamentos, dejeto sem caldo de cana-de-açúcar (DSC) e dejeto com caldo (DCC), com tempo de retenção hidráulica (TRH) de 90 dias. Para o monitoramento periódico da dinâmica da população E. coli e presença de E. coli shigatoxigenicas, do pH e da acidez volátil, realizados a cada dez dias, foram abastecidos mais 36 biodigestores bateladas, construídos de garrafas de material plástico de um litro, sendo 18 unidades para cada tratamento. A redução das populações de E. coli no decorrer do tempo foi significativa no DSC (60 dias) e no DCC (20 dias). A inativação de E. coli shigatoxigênicas ocorreu em um período mais curto, 40 dias no DSC e menos de 10 dias no DCC. Foram obtidas diferenças significativas entre os tratamentos para os valores de pH, que foram menores, e as concentrações de ácidos voláteis, que foram maiores, com adição de caldo e contribuíram para a inativação mais rápida da E. coli e STEC. A dose de caldo de cana-de-açúcar utilizada (7%) sugere a adequada sanitização do dejeto bovino leiteiro, tendo em vista a alta redução na população de E. coli e a inativação de STEC.

Efeito da secagem em leito nas características físico-químicas e microbiológicas de lodo de reator anaeróbio de fluxo ascendente usado no tratamento de esgoto sanitário / Effect of bed drying on the physico-chemical and microbiological characteristics of sludge from upflow anaerobic blanket reactor used in sewage treatment

RESUMO Os processos de tratamento de lodo de esgoto visam reduzir o teor de material orgânico biodegradável, a concentração de organismos patogênicos e a umidade a fim de se obter um material que não constitui risco à saúde ambiental e que possa ser utilizado para fins agrícolas. Nesse sentido, este trabalho teve como objetivo avaliar o efeito da secagem em leito nas características microbiológicas e físico-químicas de lodo de esgoto doméstico de reator anaeróbico de fluxo ascendente (UASB). As amostras de lodo foram retiradas a 4,8 m de profundidade (lodo A) e a 3,1 m (lodo B) do reator UASB, totalizando 3 coletas, com intervalo de 1 mês. As amostras coletadas foram submetidas ao processo de secagem em células de leitos de secagem (1,00 x 2,00 x 0,50 m). De cada célula foram coletadas 6 amostras nos tempos 0, 7, 15, 30, 60 e 90 dias. Foram determinados os parâmetros: sólidos totais, sólidos voláteis, temperatura, pH, umidade, carbono orgânico total, N, P, K, Mg, Na, Ca, Mn, Cd, Co, Cu, Ni, Pb, Zn, lipídios, coliformes totais e termotolerantes, Salmonella e ovos viáveis de helmintos. Não houve diferença físico-química, microbiológica e parasitológica entre o lodo A e o B após o período de secagem. As concentrações finais dos nutrientes, metais pesados e a relação C/N conferem aos lodos um potencial agronômico. Entretanto, a baixa inativação dos microrganismos permite concluir que o processo de secagem em leito é ineficiente para redução de patógenos. Os biossólidos gerados em ambos os tratamentos são classificados como tipo B (CONAMA 375/06).

ABSTRACT The sludge treatment process intended to reduce the content of biodegradable organic material, the concentration of pathogens and moisture in order to obtain a solid and stable material, which is not hazardous to the environment health and useful for agricultural purposes. This study aims to evaluate the effects of bed drying on physicochemical and microbiological characteristics of domestic sewage sludge samples taken from an upflow anaerobic sludge blanket (UASB) reactor. Sludge samples were collected at 4.8 m from the bottom (sludge A) and 3.1 m (sludge B) of an UASB reactor, totaling 3 collections, with an interval of 1 month. Each collected sample was subjected to the sludge drying process in cells of drying beds (1.00 x 2.00 x 0.50 m). In each cell, 6 samples were collected at 0, 7, 15, 30, 60 and 90 days. The following parameters were evaluated: total solids, volatile solids, temperature, pH, moisture content, total organic carbon, N, P, K, Mg, Na, Ca, Mn, Cd, Co, Cu, Ni, Pb, Zn, lipids, total and fecal coliforms, Salmonella and viable helminth eggs. No physical-chemical, microbiological and parasitological differences between sludge A and sludge B were detected after the period of bed drying. The final concentrations of nutrients and heavy metals as well as the C/N ratio were considered adequate for agricultural purposes. However, the low inactivation of microorganisms indicated the inefficiency of drying beds regarding the removal of pathogen microorganisms. The generated biosolids in both treatments are classified as type B (CONAMA 375/06).

Investigation of pathogen infections in Mongolian gerbils raised in a conventional facility / 中国比较医学杂志

Objective To investigate the pathogen infections of Mongolian gerbils raised in a conventional facility,and to provide a basis for the establishment of local standards for pathogen detection in Mongolian gerbils. Methods A total of 16 species of bacteria,11 species of viruses and 8 species of parasites were detected in 30 gerbils raised in a conventional facility, according to the national standards of microorganism and parasite detection in mice and rats. Results Gerbils raised in this conventional facility were infected with lymphocytic choriomeningitis virus(a positive rate of 6. 7%), sendai virus(3. 3%), pneumonia virus of mice(100. 0%), reovirus type III(6. 7%), mouse encephalomyelitis virus(10. 0%), mycoplasma spp.(6. 7%), Tyzzer's organism(6. 7%)and Helicobacter spp. (56.7%),according to our antibody detection results. Meanwhile,the detected positive rate of Pasteurella pneumotropica was 3.3%,Staphylococcus aureus 10.0%,Escherichia coli O115 a,C,K(B)6.7%,Tritrichomonas muris 100.0% and flagellates 100.0%. Conclusions The results of our study provide a reference for the establishment of classification standards for gerbils according to their pathogen and parasite infections.

Atividade antibacteriana e moduladora in vitro de extrato metanólico e hexânico de beta vulgaris spp. (Linnaeus) / Actividad antibacteriana y modulación in vitro de extractos de metanol y hexano del beta vulgaris spp. (Linnaeus) / Antibacterial activity and modulatory in vitro methanol and ethanol extracts of beta vulgaris spp. (Linnaeus)

Introdução: Beta vulgaris spp. conhecida popularmente como beterraba é bastante utilizada, além do consumo alimentar, de maneira etnofarmacológica para o combate de diversas infecções como: dores no trato gastrointestinal, inflamações crônicas, lesões nas genitais, inflamações nos ovários, cólicas, problemas renais, problemas cardíacos e diabetes. Objetivo: avaliar a atividade antibacteriana e modulatória dos extratos metanólicos e hexânicos dos frutos de B. vulgaris frente a cepas bacterianas padrões e multirresistentes, além de determinar as principais classes de metabólitos secundários. Métodos: os extratos metanólicos e hexânicos de B. vulgaris foram analisados para a atividade antibacteriana por meio de teste de microdiluição em caldo para determinação de Concentração Inibitória Mínima e modulação de aminoglicosídeos a gentamicina e amicacina. Resultados: às cepas de Staphylococcus aureus e Escherichia coli diminuiram a Concentração Inibitória Mínima de 64 µg/mL and 256 µg/mL quando combinadas aos antibióticos e extratos, Apresentando, portanto um efeito de aumento da atividade antibiótica, com exceção para o extrato hexânico em associação com a gentamicina contra cepas multirresistentes de Staphylococcus aureus. Conclusão: na prospecção fitoquímica foram evidenciados a presença de vários metabólitos secundários, o que pode explicar a ação bactericida desta planta. Portanto, diante dos resultados, B.vulgaris é uma fonte promissora no combate a resistência bacteriana(AU)

Introducción: Beta vulgaris SSP. conocido em lo popular como remolacha, es muy utilizado, además como consumo de alimentos, de manera etnofarmacológica para combatir varias infecciones como: dolores en el tracto gastrointestinal, inflamaciones crónicas, lesiones genitales, inflamaciones en ovarios, cólicos, problemas renales, diabetes y problemas del corazón. Objetivo: evaluar la actividad anti-bacteriana y moduladora de extractos metanólicos y hexânicos del fruto de B. vulgaris frente de cepas bacterianas multirresistentes estándares y además de determinar los principales metabolitos secundarios. Métodos: los extractos metanólicos y hexânicos de B. vulgaris fueron analizados para la actividad antibacteriana mediante prueba de microdilución en caldo para la determinación de la Concentración Mínima Inhibitoria y la modulación de aminoglicósidos gentamicina y amikacina. Resultados: las cepas de Staphylococcus aureus y Escherichia coli disminuyeron la Concentración Mínima Inhibitoria de 64 µ g/mL y 256 µ g/mL al combinarlos con antibióticos y los extractos, mostrando así un aumento de la actividad antibiótica. Excepto el extracto hexânico en combinación con la gentamicina contra cepas multirresistentes de Staphylococcus aureus. La fitoquímica evidencia la presencia de varios metabolitos secundarios que pueden explicar la acción bactericida de esta planta. Conclusión: los resultados de B. vulgaris muestran que es una fuente prometedora en la lucha contra la resistencia bacteriana(AU)

Introduction: Beta vulgaris spp. is popularly known as beets, widely used in ethno pharmacological way to fight various infections of the gastrointestinal tract such as pain, chronic inflammation, and sores on the genitals, inflammation of the ovaries, cramps, kidney problems, heart problems and diabetes. Objective: to evaluate the antibacterial and modulatory activity of methanol extracts of fruits and hexanic of B. vulgaris against strains of multiresistant bacterial and standards. In addition, to determining the major classes of secondary metabolites such as flavonoids and tannins. Methods: Hexane and methanol extracts of B. vulgaris were analyzed to antibacterial activity by the broth microdilution test for determination of Minimum Inhibitory Concentration and modulation and aminoglycosides such as amikacin, gentamicin. Results: the strains relevant of Escherichia coli and Staphylococcos aureus decreased Minimum Inhibitory Concentration of 64 mg/mL and 256 mg/mL thereof when combined antibiotic and extracts. Showing, so a enhancement effect of antibiotic activity, except for the hexane extract in combination with gentamicin against multidrug-resistant strains of Staphylococcus aureus. Conclusion: in phytochemical were shown the presence of various secondary metabolites, which may explain the bactericidal action of this plant. Therefore, given the results, B. vulgaris spp. is a promising source in combat bacterial resistance(AU)

Antimicrobial effects of biosynthesized silver nanoparticles produced by Actinomyces spp. based on their sizes and shapes

Aims: Actinomyces are dominant soil microflora with potent activity for production of several enzymes and metabolites. In order to increase their survival in the environment these bacteria detoxify the metal ions and consequently produce the nanoparticles. The present study was undertaken to isolate Actinomyces strains from soil samples and their evaluation for the production of silver nanoparticles with antimicrobial property. Methodology and results: Two hundred soil samples were collected and subjected to isolation and identification (based on16SrRNA gene sequencing) of silver nanoparticles producing Actinomyces. The silver nanoparticles produced by Actinomyces were confirmed by UV-visible spectral analysis, scanning electron microscope (SEM) and Inductively Coupled Plasma (ICP). Furthermore, antimicrobial property of silver nanoparticles was assessed against pathogenic microorganisms viz., Staphylococcus aureus (PTCC 1431), Acinetobacter baumannii (PTCC 19606), Bacillus cereus (PTCC 1816), Escherichia coli (PTCC 1397), Salmonella typhi (PTCC 1609), Pseudomonas aeruginosa (PTCC 1707), Aspergillus niger (PTCC 5010) and Candida albicans (PTCC 5072). Of 48 Actinomyces isolated, 26 strains could produce silver nanoparticles and three of which showed potent activity for production of silver nanoparticles. Molecular identification of these strains exhibited detection of Actinomyces amycolicicoccus subflavus, Streptomyces flavoviridis and Streptomyces lateritius. The results obtained from characterization of the biosynthesis silver nanoparticles illustrated that their shapes and sizes were spindle and spherical and 47-103 nm respectively. However, the antimicrobial effect of silver nanoparticles against the pathogenic microorganisms was varied. Yet S. typhi followed by P. aeruginosa, were more sensitive and A. baumannii was relatively less sensitive. In addition, spherical shape with small average size relatively showed more antimicrobial property. Conclusion, significance and impact of study: Soil Actinomyces could produce silver nanoparticles and these particles have antimicrobial effect. In addition, the antimicrobial effect of silver nanoparticles, not only because of their chemical property (such as formation of free radical) but also depended on their shapes and sizes.

Advances in biological spectroscopy detection of pathogenic microorganisms / 军事医学

Detection of pathogenic microorganisms has been a hot research field of microbiology.Conventional detection methods,such as isolation and culture, PCR technology, ELISA and genomic sequencing,are all time-consuming and com-plex.Because of the advantages of quick-testing, accuracy, safety and efficiency, spectroscopy has become a new non-inva-sive testing technology and has witnessed rapid development in pathogen detection and disease diagnosis.This article intro-duces three types of common spectroscopy technologies ( laser excitation fluorescence spectroscopy, infrared spectroscopy and Raman spectroscopy) , and also explains how they work in the detection of pathogenic microorganisms.

Antimicrobial Properties of Purified Bacteriocins Produced from Lactobacillus casei and Lactobacillus fermentum against Selected Pathogenic Microorganisms.

Aims: (1) To isolate bacteriocin samples produced from Lactobacillus using natural fermented foods which include: palm-wine, milk, locust beans, fufu (white solid food made from cassava), ogi (known as pap) and dairy fermented product (Yogurt); (2) extraction and purification of these bacteriocin samples using centrifugation and ammonium sulphate respectively and removal of impurities using dialysis. (3) to confirm the production of bacteriocin by performing antimicrobial assay against some selected pathogenic microorganisms. (4) to examine the effects of pH, heat and storage stability as well as biopreservative efficiency of the bacteriocin samples in pap, kunu (made from millet) and fresh orange juice; (5) to investigate the effect of viable antibiotics on the growth of isolates. Study Design: Data were analyzed using the statistical software package SPSS version 16.0 and standard errors of mean (SEM) for all the graphs plotted were represented with error bars while their characterization was designed using reciprocal of the highest dilution (2n) that resulted in the inhibition of the indicator lawn. Thus, the arbitrary units (AU) of the bacteriocin activity per milliliter (AU/ml) were defined as 2n× 1000/ 10μl. Place and Duration of Study: Microbiology Laboratory, Sacred heart Hospital, Abeokuta and Department of Microbiology, Federal University of Agriculture, Abeokuta, Ogun State, Nigeria, between March 2010 and November 2012. Methodology: Bacteriocins, otherwise known as the antimicrobial compounds were produced from the Lactobacillus strains and then isolated from Nigerian fermented foods which include: palm wine, milk, yoghurt, locust beans, ogi and fufu. These foods were isolated using de Mann Rogosa and Sharpe medium. The isolated microorganisms (L. fermentum and L.casei) were identified phenotypically after isolation. Bacteriocins were extracted and purified from the Lactobacillus strains by centrifugation, followed by ammonium sulphate precipitation and dialysis. The antimicrobial activities of the crude bacteriocins were tested against nine selected pathogenic clinical isolates collected from the University College Hospital, Ibadan. The tested isolates were Shigella dysenteriae, Shigella flexneri, Enteropathogenic Escherichia coli type 1, Enteropathogenic Escherichia coli type 2, Enterohaemorrhagic E. coli type 3, Salmonella typhi, Streptococcus pneumoniae, Staphylococcus aureus and Klebsiella pneumoniae. Results: The bacteriocins of Lactobacillus fermentum and Lactobacillus casei showed a broad range of activities and had higher significant effect (P< 0.05) on the selected pathogenic microorganisms. The effects of pH on the bacteriocins were active in range of 2 to 6. Bacteriocins produced by Lactobacillus casei were stable at 800C for 15 minutes while bacteriocins produced by Lactobacillus fermentum were stable at 1000C for 15 minutes. It was observed that these bacteriocins can be stored between -200C and 40C and they had significant difference on the selected pathogenic microorganisms (P<0.05). The preservative activities of the bacteriocins tested on different foods showed that the bacteriocin of Lactobacillus fermentum had maximum reduction on bacterial population. Lactobacillus fermentum and Lactobacillus casei isolates were resistant to erythromycin of 70% and 100% for cotrimoxazole, ciprofloxacin, augmentin and amoxicillin. Conclusion: This study showed that bacteriocins from fermented foods could be used as an effective control for pathogenic microorganisms as they were able to exhibit antimicrobial activity against the test organisms when investigated for bacteriocin production and when characterized.

Bacterial microbiota present in the gallbladder of cattle and antimicrobial resistance of Staphylococcus isolates / Microbiota bacteriana presente na vesícula biliar de bovinos e resistência antimicrobiana de isolados de Staphyloccocus

Pathogenic microorganisms can reside transiently or permanently in the gallbladder of cattle. Thus, during slaughter, more attention should be given to the gastrointestinal tract, especially to the accessory organ, the gallbladder. The main aim of this study was to characterize the bacterial microbiota present in bile and gallbladder epithelium of cattle slaughtered in a slaughtering plant under sanitary conditions and to evaluate the antimicrobial resistance in strains of the genus Staphylococcus. Thirty intact gallbladders were collected and the in bile and epithelium were researched for the presence of Aerobic Mesophilic Heterotrophic Bacteria (AMHB), Staphylococcus spp., total Enterobacteriaceae, Enterococcus spp. and Salmonella spp.The frequency of isolation of the microorganism mentioned above were, respectively: 23.02 percent, 14.39 percent, 13.67 percent, 24.46 percent, 0 percent and 24.46 percent. Concerning both gallbladder environments, the frequency of isolation of the microorganisms in the epithelium was 64.03 percent, and in the bile 35.97 percent, with no statistical difference, but with significant difference between the population averages. In antimicrobial susceptibility testing, strains of Staphylococcus from both bile and gallbladder epithelium showed sensitivity to the antimicrobials: penicillin G, ceftriaxone, chloramphenicol and gentamicin. The observation that the gallbladder supports a high frequency of microorganisms brings us to the possible fact that cattle might be a persistent carrier of pathogens of great importance to public health...

Microrganismos patogênicos podem residir temporariamente ou permanentemente na vesícula biliar de bovinos. Assim, durante o abate, maior atenção deve ser dada ao trato gastrointestinal, especialmente para o órgão acessório, a vesícula biliar. O principal objetivo deste estudo foi caracterizar a microbiota bacteriana presente na bile e no epitélio de vesículas biliares de bovinos abatidos em matadouro frigorífico sob inspeção sanitária e avaliar a resistência antimicrobiana de estirpes do gênero Staphyloccocus. Foram coletadas 30 vesículas biliares íntegras e foi pesquisada na bile e no epitélio do órgão a presença de bactérias heterotróficas aeróbias mesófilas (BHAM), Staphylococcus spp. e Enterobacteriaceae totais, Escherichia coli, Enterococcus spp. e Salmonella spp. A frequência de isolamento dos microrganismos citados acima foi, respectivamente: 23,02 por cento, 14,39 por cento, 13,67 por cento, 24,46 por cento, 0por cento e 24,46 por cento. Em relação aos dois ambientes da vesícula, a frequência de isolamento dos microrganismos no epitélio foi de 64,03 por cento, e na bile 35,97 por cento, não sendo diferente estatisticamente, mas com diferença significativa entre as médias populacionais.No teste de susceptibilidade aos antimicrobianos, as estirpes de Staphylococcus isoladas a partir da bile e do epitélio da vesícula biliar apresentaram sensibilidade a: penicilina G, ceftriaxona, cloranfenicol e gentamicina. A observação de que a vesícula biliar comporta microrganismos em elevadas frequências atenta para o fato de que o bovino possa ser um portador persistente de patógenos de grande importância em saúde pública...

Environmental safety threshold of commonly encountered highly pathogenic microor-ganisms / 军事医学

Objective To study environmental safety reference standard values of commonly encountered pathogenic microorganisms, and provide the basis for environmental risk assessment of a high-level biosafety laboratory (BSL).Methods Using human exposure dose calculation methods as the basic principle in combination with microbial hazard evaluation methods , an infectious dose calculation model of human exposure to pathogenic microorganisms by breathing was proposed . Based on research on characteristics of commonly encountered pathogenic microorganisms at home and abroad , the environ-mental safety threshold reference standard and environmental risk protection zone for such microorganisms were obtained . Results An the environmental risk assessment standard calculation method for commonly encountered highly pathogenic microorganisms was proposed , and the minimum infectious dose and environmental safety threshold of seven commonly encountered pathogenic microorganisms were obtained , including SARS coronavirus , highly pathogenic avian influenza virus, Mycobacterium tuberculosis, Bacillus anthracis, Yersinia pestis,Francisella tularensis, and epidemic hemorrhagic fever virus.Conclusion The results can be used as a reference standard of infectious aerosols in a high-level BSL for environ-mental risk assessment , laboratory risk control and emergency management .

Research on transmission risk exposure of pathogenic microorganisms in anesthesia procedures / 中华医院管理杂志

Objective To raise risk exposure awareness for spreading pathogenic microorganisms in anesthesia procedures and normalize aseptic technique of anesthesiologists,thus minimizing postoperative infection.Methods Choose 45 cases of general anesthesia.Respectively before anesthesia induction (Time0),five minutes after induction (Time1) and two hours after anesthesia (Time2),make bacteriological tests on seven spots vulnerable to contamination,including the three-way stopcock,screwtype hose coupling,oxygen flux knob,pressure-release valve surface,exhaled breath entry of the anesthesia machine,oxygen intake of the breathing loop of the anesthesia machine,and operating desktop of the anesthesia cart.Results Contamination risk exposure of the stopcock extends with the operative time.At Time 0,it is sterile; at Time 1,84.4％of the 45 cases are found with bacteria growth,with colony count of 1～2CFU/ml; at Time2,colony counts at various monitoring points range 7～21 CFU/ml,of which the differences between Timel group and Time0,as well as Time2 and Time0 are statistically significant(P＜0.05).Colony counts at other monitoring points comply with the regulations.Conclusion Three-way stopcocks are highly vulnerable to contamination during operative anesthesia.Regular sterile operations can effectively prevent and lower postoperative infection of the patients.

Antimicrobial action of lactoferrin on Staphylococcus aureus inoculated in Minas frescal cheese

The effect of the addition of lactoferrin on Staphylococcus aureus to Minas frescal cheese was evaluated. Three cheeses were made: control (S. aureus), Lf-2% (2% lactoferrin + S. aureus) and Lf-4% (4% lactoferrin + S. aureus). Cheeses were packaged and S. aureus populations were determined on days 1, 8, 15, 22 and 29 of storage at 6°C. The experiment was repeated three times. S. aureus population increased 1.3 logarithmic cycles in the control cheese during storage, while it decreased to numbers below the detection limit in cheeses containing lactoferrin, over the same period. Moreover, antimicrobial effect showed to be dose-dependent.

Ação antimicrobiana de lactoferrina sobre Staphylococcus aureus inoculado em queijo Minas frescal. O efeito da adição de lactoferrina sobre a viabilidade de Staphylococcus aureus inoculado em queijo Minas frescal foi avaliado. Três queijos foram produzidos: controle (S. aureus), Lf-2% (2% lactoferrina + S. aureus) e Lf-4% (4% lactoferrina + S. aureus). Os queijos foram armazenados e as populações de S. aureus foram determinadas durante o armazenamento refrigerado a 6°C nos dias 1, 8, 15, 22 e 29. Os experimentos foram realizados em triplicata. As populações de S. aureus aumentaram 1,3 ciclos logarítmicos nos queijos controle durante o armazenamento, enquanto que essas populações foram reduzidas abaixo do limite de detecção nos queijos contendo lactoferrina no mesmo período. Além disso, observou-se que o efeito antimicrobiano foi dose-dependente.