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Sample records for polymicrobial culture-negative samples

  1. Bacterial community profiling of milk samples as a means to understand culture-negative bovine clinical mastitis.

    PubMed

    Kuehn, Joanna S; Gorden, Patrick J; Munro, Daniel; Rong, Ruichen; Dong, Qunfeng; Plummer, Paul J; Wang, Chong; Phillips, Gregory J

    2013-01-01

    Inflammation and infection of bovine mammary glands, commonly known as mastitis, imposes significant losses each year in the dairy industry worldwide. While several different bacterial species have been identified as causative agents of mastitis, many clinical mastitis cases remain culture negative, even after enrichment for bacterial growth. To understand the basis for this increasingly common phenomenon, the composition of bacterial communities from milk samples was analyzed using culture independent pyrosequencing of amplicons of 16S ribosomal RNA genes (16S rDNA). Comparisons were made of the microbial community composition of culture negative milk samples from mastitic quarters with that of non-mastitic quarters from the same animals. Genomic DNA from culture-negative clinical and healthy quarter sample pairs was isolated, and amplicon libraries were prepared using indexed primers specific to the V1-V2 region of bacterial 16S rRNA genes and sequenced using the Roche 454 GS FLX with titanium chemistry. Evaluation of the taxonomic composition of these samples revealed significant differences in the microbiota in milk from mastitic and healthy quarters. Statistical analysis identified seven bacterial genera that may be mainly responsible for the observed microbial community differences between mastitic and healthy quarters. Collectively, these results provide evidence that cases of culture negative mastitis can be associated with bacterial species that may be present below culture detection thresholds used here. The application of culture-independent bacterial community profiling represents a powerful approach to understand long-standing questions in animal health and disease.

  2. Bacterial Community Profiling of Milk Samples as a Means to Understand Culture-Negative Bovine Clinical Mastitis

    PubMed Central

    Kuehn, Joanna S.; Gorden, Patrick J.; Munro, Daniel; Rong, Ruichen; Dong, Qunfeng; Plummer, Paul J.; Wang, Chong; Phillips, Gregory J.

    2013-01-01

    Inflammation and infection of bovine mammary glands, commonly known as mastitis, imposes significant losses each year in the dairy industry worldwide. While several different bacterial species have been identified as causative agents of mastitis, many clinical mastitis cases remain culture negative, even after enrichment for bacterial growth. To understand the basis for this increasingly common phenomenon, the composition of bacterial communities from milk samples was analyzed using culture independent pyrosequencing of amplicons of 16S ribosomal RNA genes (16S rDNA). Comparisons were made of the microbial community composition of culture negative milk samples from mastitic quarters with that of non-mastitic quarters from the same animals. Genomic DNA from culture-negative clinical and healthy quarter sample pairs was isolated, and amplicon libraries were prepared using indexed primers specific to the V1–V2 region of bacterial 16S rRNA genes and sequenced using the Roche 454 GS FLX with titanium chemistry. Evaluation of the taxonomic composition of these samples revealed significant differences in the microbiota in milk from mastitic and healthy quarters. Statistical analysis identified seven bacterial genera that may be mainly responsible for the observed microbial community differences between mastitic and healthy quarters. Collectively, these results provide evidence that cases of culture negative mastitis can be associated with bacterial species that may be present below culture detection thresholds used here. The application of culture-independent bacterial community profiling represents a powerful approach to understand long-standing questions in animal health and disease. PMID:23634219

  3. Evaluation of the detection of Mycobacterium tuberculosis with metabolic activity in culture-negative human clinical samples.

    PubMed

    Cubero, N; Esteban, J; Palenque, E; Rosell, A; Garcia, M J

    2013-03-01

    Mycobacterium tuberculosis is assumed to remain in a quiescent state during latent infection, being unable to grow in culture. The aim of this study was to evaluate the detection of viable but non-cultivable bacilli with metabolic activity in human clinical samples using a procedure that is independent of the immunological status of the patient. The study was performed on 66 human clinical samples, from patients subjected to routine diagnosis to rule out a mycobacterial infection. Specimens from pulmonary and extra-pulmonary origins were verified to contain human DNA before testing for M. tuberculosis DNA, rRNA and transient RNA by real-time quantitative PCR. Clinical records of 55 patients were also reviewed. We were able to detect viable but non-cultivable bacilli with a metabolic activity in both pulmonary and extra-pulmonary samples. Mycobacterium tuberculosis RNA was detected in the majority of culture-positive samples whereas it was detected in one-third of culture-negative samples, 20% of them showed metabolic activity. Amplifications of the ftsZ gene and particularly of the main promoter of the ribosomal operon rrnA, namely PCL1, seem to be good targets to detect active bacilli putatively involved in latent infection. Moreover, this last target would provide information on the basal metabolic activity of the bacilli detected. © 2012 The Authors. Clinical Microbiology and Infection © 2012 European Society of Clinical Microbiology and Infectious Diseases.

  4. Rapid identification of fungi in culture-negative clinical blood and respiratory samples by DNA sequence analyses.

    PubMed

    Sidiq, Farida; Hoostal, Matt; Rogers, Scott O

    2016-06-07

    Clinical diagnoses of fungal infections often rely upon culture techniques followed by microscopic examination of positive cultures and histopathological specimens. Culturing of microorganisms is prone to false negatives, while microscopy methods can be complicated by atypical phenotypes and organisms that are morphologically indistinguishable in tissues. Delays in diagnoses (or the lack thereof) and inaccurate identification of infectious organisms contribute to increased morbidity and mortality in patients. Two-hundred randomized, heterogeneous patient blood and respiratory samples that were culture-negative were tested using polymerase chain reaction (PCR) amplification of internal transcribed spacer regions of ribosomal RNA genes utilizing panfungal primers. Amplicons were sequenced, subjected to sequence similarity searches, and compared using phylogenetic analyses. Thirteen fungal sequences were detected in three whole-blood samples and nine respiratory samples. Bioinformatic analyses were performed which indicated the presence of multiple pathogens and potential pathogens. The results from this pilot study demonstrate the utility of PCR assays and sequence analyses in clinical tests for fungi to facilitate rapid diagnosis and appropriate treatments to deal with the false negatives from culture results.

  5. Culture-negative endocarditis

    MedlinePlus

    ... inflammation of the lining of one or more heart valves, but no endocarditis-causing germs can be found ... the heart, where they can settle on damaged heart valves. Alternative Names Endocarditis (culture-negative) Images Culture-negative ...

  6. Identification of Common Bacterial Pathogens Causing Meningitis in Culture-Negative Cerebrospinal Fluid Samples Using Real-Time Polymerase Chain Reaction

    PubMed Central

    2016-01-01

    Background. Meningitis is a serious communicable disease with high morbidity and mortality rates. It is an endemic disease in Egypt caused mainly by Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. In some settings, bacterial meningitis is documented depending mainly on positive cerebrospinal fluid (CSF) culture results or CSF positive latex agglutination test, missing the important role of prior antimicrobial intake which can yield negative culture and latex agglutination test results. This study aimed to utilize molecular technology in order to diagnose bacterial meningitis in culture-negative CSF samples. Materials and Methods. Forty culture-negative CSF samples from suspected cases of bacterial meningitis were examined by real-time polymerase chain reaction (real-time PCR) for the presence of lytA, bexA, and ctrA genes specific for Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis, respectively. Results. Positive real-time PCR results for Streptococcus pneumoniae were detected in 36 (90%) of culture-negative CSF samples while no positive results for Haemophilus influenzae or Neisseria meningitidis were detected. Four (10%) samples were negative by real-time PCR for all tested organisms. Conclusion. The use of molecular techniques as real-time PCR can provide a valuable addition to the proportion of diagnosed cases of bacterial meningitis especially in settings with high rates of culture-negative results. PMID:27563310

  7. The Optimization of Molecular Detection of Clinical Isolates of Brucella in Blood Cultures by eryD Transcriptase Gene for Confirmation of Culture-Negative Samples

    PubMed Central

    Tabibnejad, Mahsa; Alikhani, Mohammad Yousef; Arjomandzadegan, Mohammad; Hashemi, Seyed Hamid; Naseri, Zahra

    2016-01-01

    Background Brucellosis is a zoonosis disease which is widespread across the world. Objectives The aim of the present study is the evaluation of culture-negative blood samples. Materials and Methods A total of 100 patients with suspected brucellosis were included in this experimental study and given positive serological tests. Diagnosis was performed on patients with clinical symptoms of the disease, followed by the detection of a titer that was equal to or more than 1:160 (in endemic areas) by the standard tube agglutination method. Blood samples were cultured by a BACTEC 9050 system, and subsequently by Brucella agar. At the same time, DNA from all blood samples was extracted by Qiagen Kit Company (Qia Amp Mini Kit). A molecular assay of blood samples was carried out by detection of eryD transcriptase and bcsp 31 genes in specific double PCR reactions. The specificity of the primers was evaluated by DNA from pure and approved Brucella colonies found in the blood samples, by DNA from other bacteria, and by ordinary PCR. DNA extraction from the pure colonies was carried out by both Qiagen Kit and Chelex 100 methods; the two were compared. Results 39 cases (39%) had positive results when tested by the BACTEC system, and 61 cases (61%) became negative. 23 culture-positive blood samples were randomly selected for PCR reactions; all showed 491 bp for the eryD gene and 223 bp for the bcsp 31 gene. Interestingly, out of 14 culture-negative blood samples, 13 cases showed positive bonds in PCR. The specificity of the PCR method was equal to 100%. DNA extraction from pure cultures was done by both Chelex 100 and Qiagen Kit; these showed the same results for all samples. Conclusions The results prove that the presented double PCR method could be used to detect positive cases from culture-negative blood samples. The Chelex 100 method is simpler and safer than the use of Qiagen Kit for DNA extraction. PMID:27330831

  8. The Optimization of Molecular Detection of Clinical Isolates of Brucella in Blood Cultures by eryD Transcriptase Gene for Confirmation of Culture-Negative Samples.

    PubMed

    Tabibnejad, Mahsa; Alikhani, Mohammad Yousef; Arjomandzadegan, Mohammad; Hashemi, Seyed Hamid; Naseri, Zahra

    2016-04-01

    Brucellosis is a zoonosis disease which is widespread across the world. The aim of the present study is the evaluation of culture-negative blood samples. A total of 100 patients with suspected brucellosis were included in this experimental study and given positive serological tests. Diagnosis was performed on patients with clinical symptoms of the disease, followed by the detection of a titer that was equal to or more than 1:160 (in endemic areas) by the standard tube agglutination method. Blood samples were cultured by a BACTEC 9050 system, and subsequently by Brucella agar. At the same time, DNA from all blood samples was extracted by Qiagen Kit Company (Qia Amp Mini Kit). A molecular assay of blood samples was carried out by detection of eryD transcriptase and bcsp 31 genes in specific double PCR reactions. The specificity of the primers was evaluated by DNA from pure and approved Brucella colonies found in the blood samples, by DNA from other bacteria, and by ordinary PCR. DNA extraction from the pure colonies was carried out by both Qiagen Kit and Chelex 100 methods; the two were compared. 39 cases (39%) had positive results when tested by the BACTEC system, and 61 cases (61%) became negative. 23 culture-positive blood samples were randomly selected for PCR reactions; all showed 491 bp for the eryD gene and 223 bp for the bcsp 31 gene. Interestingly, out of 14 culture-negative blood samples, 13 cases showed positive bonds in PCR. The specificity of the PCR method was equal to 100%. DNA extraction from pure cultures was done by both Chelex 100 and Qiagen Kit; these showed the same results for all samples. The results prove that the presented double PCR method could be used to detect positive cases from culture-negative blood samples. The Chelex 100 method is simpler and safer than the use of Qiagen Kit for DNA extraction.

  9. Rapid 16S rRNA next-generation sequencing of polymicrobial clinical samples for diagnosis of complex bacterial infections.

    PubMed

    Salipante, Stephen J; Sengupta, Dhruba J; Rosenthal, Christopher; Costa, Gina; Spangler, Jessica; Sims, Elizabeth H; Jacobs, Michael A; Miller, Samuel I; Hoogestraat, Daniel R; Cookson, Brad T; McCoy, Connor; Matsen, Frederick A; Shendure, Jay; Lee, Clarence C; Harkins, Timothy T; Hoffman, Noah G

    2013-01-01

    Classifying individual bacterial species comprising complex, polymicrobial patient specimens remains a challenge for culture-based and molecular microbiology techniques in common clinical use. We therefore adapted practices from metagenomics research to rapidly catalog the bacterial composition of clinical specimens directly from patients, without need for prior culture. We have combined a semiconductor deep sequencing protocol that produces reads spanning 16S ribosomal RNA gene variable regions 1 and 2 (∼360 bp) with a de-noising pipeline that significantly improves the fraction of error-free sequences. The resulting sequences can be used to perform accurate genus- or species-level taxonomic assignment. We explore the microbial composition of challenging, heterogeneous clinical specimens by deep sequencing, culture-based strain typing, and Sanger sequencing of bulk PCR product. We report that deep sequencing can catalog bacterial species in mixed specimens from which usable data cannot be obtained by conventional clinical methods. Deep sequencing a collection of sputum samples from cystic fibrosis (CF) patients reveals well-described CF pathogens in specimens where they were not detected by standard clinical culture methods, especially for low-prevalence or fastidious bacteria. We also found that sputa submitted for CF diagnostic workup can be divided into a limited number of groups based on the phylogenetic composition of the airway microbiota, suggesting that metagenomic profiling may prove useful as a clinical diagnostic strategy in the future. The described method is sufficiently rapid (theoretically compatible with same-day turnaround times) and inexpensive for routine clinical use.

  10. Virulence determinants in clinical Staphylococcus aureus from monomicrobial and polymicrobial infections of diabetic foot ulcers.

    PubMed

    Shettigar, Kavitha; Jain, Spoorthi; Bhat, Deepika V; Acharya, Raviraj; Ramachandra, Lingadakai; Satyamoorthy, Kapaettu; Murali, Thokur Sreepathy

    2016-12-01

    Antibiotic resistance in Staphylococcus aureus is a major public health concern, and methicillin-resistant S. aureus has emerged as an important pathogen. We characterized S. aureus isolates from monomicrobial and polymicrobial wound infections from 200 diabetic individuals with foot ulcers to understand their underlying diversity and pathogenicity. Staphylococcal cassette chromosome mec typing was performed, and genes coding for production of biofilm, Panton-Valentine leukocidin, toxic shock syndrome toxin and leukotoxins DE and M were screened. Biofilm production was also quantified by the tissue culture plate method. Strains were genotyped using multilocus sequence typing, multiple-locus variable number tandem repeat analysis and repetitive sequence PCR methods. Polymicrobial infections were present in 115 samples, 61 samples showed monomicrobial infection and 24 samples were culture negative. Polymicrobial infections were significantly higher in patients with previous amputation history. Of the 86 samples infected with S. aureus, virulence genes were found in 81 isolates, and 41 isolates possessed more than one virulence gene. Strains which contained pvl gene alone or luk-DE alone were significantly higher in polymicrobial wounds. Based on biofilm production, 18.6 % of isolates were classified as high, 24.4 % as moderate and 57 % as low biofilm producers. Genotyping of 30 strains revealed 10 different sequence types with a strong association among sequence types, specific virulence markers and antibiotic resistance profiles. Moreover, isolates from monomicrobial and polymicrobial wounds differed significantly in their virulence potential and the sequence types to which they belonged, and these are helpful in mapping the evolution of the identified strains of S. aureus.

  11. Biofilm models of polymicrobial infection

    PubMed Central

    Gabrilska, Rebecca A; Rumbaugh, Kendra P

    2015-01-01

    Interactions between microbes are complex and play an important role in the pathogenesis of infections. These interactions can range from fierce competition for nutrients and niches to highly evolved cooperative mechanisms between different species that support their mutual growth. An increasing appreciation for these interactions, and desire to uncover the mechanisms that govern them, has resulted in a shift from monomicrobial to polymicrobial biofilm studies in different disease models. Here we provide an overview of biofilm models used to study select polymicrobial infections and highlight the impact that the interactions between microbes within these biofilms have on disease progression. Notable recent advances in the development of polymicrobial biofilm-associated infection models and challenges facing the study of polymicrobial biofilms are addressed. PMID:26592098

  12. Diverticular Pylephlebitis and Polymicrobial Septicemia

    PubMed Central

    Punjabi, Chitra

    2017-01-01

    Diverticulitis primarily affects the sigmoid colon and is often complicated by intra-abdominal abscesses and fistulas. Rarely, however, mesenteric venous thrombosis has been known to occur. Optimal management is still unclear. We report the first case of polymicrobial sepsis resulting from diverticular pylephlebitis, managed successfully with bowel rest, antibiotics, and anticoagulation. PMID:28163946

  13. Update on blood culture-negative endocarditis.

    PubMed

    Tattevin, P; Watt, G; Revest, M; Arvieux, C; Fournier, P-E

    2015-01-01

    Blood culture-negative endocarditis is often severe, and difficult to diagnose. The rate of non-documented infective endocarditis has decreased with the advent of molecular biology - improved performance for the diagnosis of bacterial endocarditis with blood cultures sterilized by previous antibacterial treatment - and cardiac surgery - access to the main infected focus, the endocardium, for half of the patients. Blood culture-negative endocarditis are classified in 3 main categories: (i) bacterial endocarditis with blood cultures sterilized by previous antibacterial treatment (usually due to usual endocarditis-causing bacteria, i.e. streptococci, more rarely staphylococci, or enterococci); (ii) endocarditis related to fastidious microorganisms (e.g. HACEK bacteria; defective streptococci - Gemella, Granulicatella, and Abiotrophia sp. - Propionibacterium acnes, Candida sp.): in these cases, prolonged incubation will allow identifying the causative pathogen in a few days; (iii) and the "true" blood culture-negative endocarditis, due to intra-cellular bacteria that cannot be routinely cultured in blood with currently available techniques: in France, these are most frequently Bartonella sp., Coxiella burnetti (both easily diagnosed by ad hoc serological tests), and Tropheryma whipplei (usually diagnosed by PCR on excised cardiac valve tissue). Non-infective endocarditis is rare, mostly limited to marantic endocarditis, and the rare endocarditis related to systemic diseases (lupus, Behçet).

  14. The biogeography of polymicrobial infection

    PubMed Central

    Stacy, Apollo; McNally, Luke; Darch, Sophie E.; Brown, Sam P.; Whiteley, Marvin

    2016-01-01

    Microbial communities are spatially organized in both the environment and the human body. Although patterns exhibited by these communities are described by microbial biogeography this discipline has previously only considered large-scale, global patterns. By contrast, the fine-scale positioning of a pathogen within an infection site can greatly alter its virulence potential. In this Review, we highlight the importance of considering spatial positioning in the study of polymicrobial infections and discuss targeting biogeography as a therapeutic strategy. PMID:26714431

  15. Clues to diagnosing culture negative Listeria rhombencephalitis.

    PubMed

    O'Callaghan, Marguerite; Mok, Tzehow; Lefter, Stela; Harrington, Hugh

    2012-09-30

    A previously healthy 35-year-old Caucasian woman developed left body (including facial) hemianaesthesia, asymmetrical lower cranial nerve palsies and cerebellar signs after a 4-day history of headache, nausea and vomiting. Serial blood and cerebrospinal fluid (CSF) cultures returned negative for a culprit organism. CSF examination revealed a lymphocytic pleocytosis and an elevated protein count. CSF cytological examination identified plasma cells. MRI of brain showed multiple ring-enhancing 'abscess-like' lesions in the brainstem and upper cervical cord together with abnormal meningeal enhancement. A decision was made to treat her empirically for Listeria rhombencephalitis to which she responded completely. CSF PCR eventually returned positive for Listeria monocytogenes. This case illustrates the utility of clinical features, MRI, CSF cytology and PCR in diagnosis and treatment of culture negative L monocytogenes rhombencephalitis in an immunocompetent individual.

  16. Culture-Negative Severe Sepsis: Nationwide Trends and Outcomes.

    PubMed

    Gupta, Shipra; Sakhuja, Ankit; Kumar, Gagan; McGrath, Eric; Nanchal, Rahul S; Kashani, Kianoush B

    2016-12-01

    Although 28% to 49% of severe sepsis hospitalizations have been described as being "culture negative," there are very limited data on the epidemiology and outcomes of those with culture-negative severe sepsis (CNSS). The objectives of this study were to investigate the proportion and trends of CNSS and its association with mortality. Using the Nationwide Inpatient Sample (NIS) database from 2000 to 2010, we identified adults hospitalized with severe sepsis. Those without any specific organism codes were identified as "with CNSS." We examined the proportion of CNSS hospitalizations and rates of mortality associated with it. We also assessed the independent effect of CNSS on mortality. Of 6,843,279 admissions of patients with severe sepsis, 3,226,406 (47.1%) had culture-negative results. The age-adjusted proportion of CNSS increased from 33.9% in 2000 to 43.5% in 2010 (P < .001). Those with CNSS had more comorbidities, acute organ dysfunction (respiratory, cardiac, hepatic, and renal dysfunction), and in-hospital mortality (34.6% vs 22.7%; P < .001), although acute kidney injury requiring dialysis was less frequent (5.3% vs 6.1%; P < .001). CNSS was an independent predictor of mortality in those with severe sepsis (OR, 1.75; 95% CI, 1.72-1.77). CNSS among hospitalized patients is common, and its proportion is on the rise. CNSS is associated with greater acute organ dysfunction and mortality. Having CNSS is an independent predictor of death. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  17. Identification of torque teno virus in culture-negative endophthalmitis by representational deep DNA sequencing.

    PubMed

    Lee, Aaron Y; Akileswaran, Lakshmi; Tibbetts, Michael D; Garg, Sunir J; Van Gelder, Russell N

    2015-03-01

    To test the hypothesis that uncultured organisms may be present in cases of culture-negative endophthalmitis by use of deep DNA sequencing of vitreous biopsies. Single-center, consecutive, prospective, observational study. Aqueous or vitreous biopsies from 21 consecutive patients presenting with presumed infectious endophthalmitis and 7 vitreous samples from patients undergoing surgery for noninfectious retinal disorders. Traditional bacterial and fungal culture, 16S quantitative polymerase chain reaction (qPCR), and a representational deep-sequencing method (biome representational in silico karyotyping [BRiSK]) were applied in parallel to samples to identify DNA sequences corresponding to potential pathogens. Presence of potential pathogen DNA in ocular samples. Zero of 7 control eyes undergoing routine vitreous surgery yielded positive results for bacteria or virus by culture or 16S polymerase chain reaction (PCR). A total of 14 of the 21 samples (66.7%) from eyes harboring suspected infectious endophthalmitis were culture-positive, the most common being Staphylococcal and Streptococcal species. There was good agreement among culture, 16S bacterial PCR, and BRiSK methodologies for culture-positive cases (Fleiss' kappa of 0.621). 16S PCR did not yield a recognizable pathogen sequence in any culture-negative sample, whereas BRiSK suggested the presence of Streptococcus in 1 culture-negative sample. With the use of BRiSK, 57.1% of culture-positive and 100% of culture-negative samples demonstrated the presence of torque teno virus (TTV) sequences, compared with none in the controls (P=0.0005, Fisher exact test). The presence of TTV viral DNA was confirmed in 7 cases by qPCR. No other known viruses or potential pathogens were identified in these samples. Culture, 16S qPCR, and BRiSK provide complementary information in presumed infectious endophthalmitis. The majority of culture-negative endophthalmitis samples did not contain significant levels of bacterial DNA

  18. Metagenomic analysis for detecting pathogens in culture-negative infective endocarditis.

    PubMed

    Fukui, Yuto; Aoki, Kotaro; Okuma, Shinnosuke; Sato, Takahiro; Ishii, Yoshikazu; Tateda, Kazuhiro

    2015-12-01

    Pathogen identification is important for proper diagnosis and optimal treatment of infective endocarditis (IE). Blood and valve cultures are the gold standard for detecting pathogens responsible for IE. However, these tests only detect culturable pathogens, and have low sensitivity, especially in patients previously treated with antibiotics. Culture-negative IE is still a major clinical problem and a diagnostic challenge. Recently, metagenomic analysis using next generation sequencing has been used to detect pathogens directly from clinical samples. However, there are very few reports of the use of metagenomic analysis for pathogen identification in culture-negative IE cases and the usefulness of this new method is unknown. Here, we report a case of successful pathogen detection with metagenomic analysis in a patient of culture-negative IE. The patient underwent valve replacement surgery and received antibiotics for 5 weeks and survived. Using metagenomic analysis of resected vegetation, we detected Abiotrophia defectiva, which is often associated with culture-negative IE due to its fastidious growth. This method may be useful for pathogen identification in future cases of culture-negative IE.

  19. Identification of torque teno virus in culture-negative endophthalmitis by representational deep-DNA sequencing

    PubMed Central

    Lee, Aaron Y.; Akileswaran, Lakshmi; Tibbetts, Michael D.; Garg, Sunir J.; Van Gelder, Russell N.

    2014-01-01

    Purpose To test the hypothesis that uncultured organisms may be present in cases of culture-negative endophthalmitis, by use of deep DNA sequencing of vitreous biopsies. Design Single center consecutive prospective observational study. Participants and Controls Aqueous or vitreous biopsies from 21 consecutive patients presenting with presumed infectious endophthalmitis, and seven vitreous samples from patients undergoing surgery for non-infectious retinal disorders. Methods Traditional bacterial and fungal culture, 16S quantitative polymerase chain reaction (qPCR) and a representational deep-sequencing method (Biome Representational in Silico Karyotyping [BRiSK]) were applied in parallel to samples to identify DNA sequences corresponding to potential pathogens. Main Outcome Measures Presence of potential pathogen DNA in ocular samples. Results None of 7 control eyes undergoing routine vitreous surgery yielded positive results for bacteria or virus by culture or 16S PCR. Fourteen of the 21 samples (66.7%) from eyes harboring suspected infectious endophthalmitis were culture-positive, the most common being Staphylococcal and Streptococcal species. There was good agreement among culture, 16S bacterial PCR, and BRiSK methodologies for culture-positive cases (Fleiss’ kappa of 0.621). 16S PCR did not yield a recognizable pathogen sequence in any culture-negative sample, while BRiSK suggested presence of Steptococcus in one culture-negative sample. Surprisingly, using BRiSK, 57.1% of culture-positive and 100% of culture-negative samples demonstrated presence of Torque Teno Virus (TTV) sequences, compared to none in the controls (Fisher exact, p = 0.0005). Presence of TTV viral DNA was confirmed in seven cases by qPCR. No other known viruses or potential pathogens were identified in these samples. Conclusion Culture, 16S qPCR, and BRiSK provide complementary information in presumed infectious endophthalmitis. The majority of culture-negative endophthalmitis samples did

  20. Absence of bacterial DNA in culture-negative urine from cats with and without lower urinary tract disease.

    PubMed

    Lund, Heidi Sjetne; Skogtun, Gaute; Sørum, Henning; Eggertsdóttir, Anna Vigdís

    2015-10-01

    A diagnosis of bacterial cystitis commonly relies on a positive microbiological culture demonstrating the presence of a significant number of colony-forming units/ml urine, as urine within the upper urinary tract, bladder and proximal urethra generally is considered sterile. Recent studies from human and veterinary medicine indicate the presence of non-culturable bacteria in culture-negative urine samples. The aim of the present study was to determine the occurrence of bacterial DNA in culture-negative urine samples from cats with signs of feline lower urinary tract disease (FLUTD) and healthy control cats by 16S ribosomal DNA PCR and subsequent sequencing. The study sample included 38 culture-negative urine samples from cats with FLUTD and 43 culture-negative samples from control cats. Eight culture-positive urine samples from cats with FLUTD were included as external positive controls in addition to negative reaction controls. Of possible methodological limitations, degradation of DNA due to storage, the use of non-sedimented urine for DNA isolation and lack of internal positive reaction controls should be mentioned. The positive controls were recognised, but occurrence of bacterial DNA in culture-negative urine from cats with or without signs of lower urinary tract disease was not demonstrated. However, considering the possible methodological limitations, the presence of bacterial DNA in the urine of culture-negative FLUTD cats cannot be excluded based on the present results alone. Therefore, a prospective study reducing the possibility of degradation of DNA due to storage, in combination with modifications enhancing the chance of detecting even lower levels of bacterial DNA in culture-negative samples, seems warranted. © ISFM and AAFP 2014.

  1. Predictors of fifty days in-hospital mortality in patients with culture negative neutrocytic ascites.

    PubMed

    Bal, Chinmaya Kumar; Bhatia, Vikram; Daman, Ripu

    2017-05-16

    Culture negative neutrocytic ascites is a variant of spontaneous bacterial peritonitis. But there are conflicting reports regarding the mortality associated with culture negativeneutrocytic ascites. Therefore we aim to determine the predictors of mortality associated with culture negativeneutrocytic ascites in a larger sample population. We analysed 170 patients consecutively admitted to intensive care unit with diagnosis of culture negative neutrocytic ascites. The clinical, laboratory parameters, etiology of liver cirrhosis was determined along with the scores like model for end stage liver disease, child turcotte pugh were recorded. The 50 day in-hospital mortality rate in culture negative neutrocytic ascites was 39.41% (n = 67). In univariate analysis, means of parameters like total leucocyte count, urea, bilirubin, alanine transaminase, aspartate transaminase, international normalized ratio, acute kidney injury, septic shock, hepatic encephalopathy and model for end stage liver disease were significantly different among survived and those who died (P value ≤0.05). Cox proportional regression model showed the hazard ratio (HR) of acute kidney injury was 2.212 (95% CI: 1.334-3.667), septic shock (HR = 1.895, 95% CI: 1.081-3.323) and model for end stage liver disease (HR = 1.054, 95% CI: 1.020-1.090). Receiver operating characteristics curve showed aspartate aminotransferase (AST) had highest area under the curve 0.761 (95% CI: 0.625-0.785). Patients with culture negative neutrocytic ascites have a mortality rate comparable to spontaneous bacterial peritonitis. aspartate aminotransferase, alanine aminotransferase (ALT), acute kidney injury (AKI), model for end stage liver disease (MELD) and septic shock are the independent predictors of 50 days in-hospital mortality in culture negative neutrocytic ascites.

  2. Polymicrobial synergy and dysbiosis in inflammatory disease

    PubMed Central

    Lamont, Richard J.; Hajishengallis, George

    2014-01-01

    Uncontrolled inflammation of the periodontal area may arise when complex microbial communities transition from a commensal to a pathogenic entity. Communication among constituent species leads to polymicrobial synergy among metabolically compatible organisms that acquire functional specialization within the developing community. Keystone pathogens, even at low abundance, elevate community virulence and the resulting dysbiotic community targets specific aspects of host immunity to further disable immune surveillance while promoting an overall inflammatory response. Inflammophilic organisms benefit from proteinaceous substrates derived from inflammatory tissue breakdown. Inflammation and dysbiosis reinforce each other and the escalating environmental changes further select for a pathobiotic community. We have synthesized the polymicrobial synergy and dysbiotic components of the process into a new model for inflammatory diseases. PMID:25498392

  3. Polymicrobial synergy and dysbiosis in inflammatory disease.

    PubMed

    Lamont, Richard J; Hajishengallis, George

    2015-03-01

    Uncontrolled inflammation of the periodontal area may arise when complex microbial communities transition from a commensal to a pathogenic entity. Communication among constituent species leads to polymicrobial synergy between metabolically compatible organisms that acquire functional specialization within the developing community. Keystone pathogens, even at low abundance, elevate community virulence, and the resulting dysbiotic community targets specific aspects of host immunity to further disable immune surveillance while promoting an overall inflammatory response. Inflammophilic organisms benefit from proteinaceous substrates derived from inflammatory tissue breakdown. Inflammation and dysbiosis reinforce each other, and the escalating environmental changes further select for a pathobiotic community. We have synthesized the polymicrobial synergy and dysbiotic components of the process into a new model for inflammatory diseases.

  4. Polymicrobial Infective Endocarditis: Clinical Features and Prognosis

    PubMed Central

    García-Granja, Pablo Elpidio; López, Javier; Vilacosta, Isidre; Ortiz-Bautista, Carlos; Sevilla, Teresa; Olmos, Carmen; Sarriá, Cristina; Ferrera, Carlos; Gómez, Itziar; Román, José Alberto San

    2015-01-01

    Abstract To describe the profile of left-sided polymicrobial endocarditis (PE) and to compare it with monomicrobial endocarditis (ME). Among 1011 episodes of left-sided endocarditis consecutively diagnosed in 3 tertiary centers, between January 1, 1996 and December 31, 2014, 60 were polymicrobial (5.9%), 821 monomicrobial (81.7%), and in 123 no microorganism was detected (12.2%). Seven patients (0.7%) were excluded from the analysis because contamination of biologic tissue could not be discarded. The authors described the clinical, microbiologic, echocardiographic, and outcome of patients with PE and compared it with ME. Mean age was 64 years SD 16 years, 67% were men and 30% nosocomial. Diabetes mellitus (35%) were the most frequent comorbidities, fever (67%) and heart failure (43%) the most common symptoms at admission. Prosthetic valves (50%) were the most frequent infection location and coagulase-negative Staphylococci (48%) and enterococci (37%) the leading etiologies. The most repeated combination was coagulase-negative Staphylococci with enterococci (n = 9). Polymicrobial endocarditis appeared more frequently in patients with underlying disease (70% versus 56%, P = 0.036), mostly diabetics (35% versus 24%, P = 0.044) with previous cardiac surgery (15% versus 8% P = 0.049) and prosthetic valves (50% versus 37%, P = 0.038). Coagulase-negative Staphylococci, enterococci, Gram-negative bacilli, anaerobes, and fungi were more frequent in PE. No differences on age, sex, symptoms, need of surgery, and in-hospital mortality were detected. Polymicrobial endocarditis represents 5.9% of episodes of left-sided endocarditis in our series. Despite relevant demographic and microbiologic differences between PE and ME, short-term outcome is similar. PMID:26656328

  5. Nasopharyngeal polymicrobial colonization during health, viral upper respiratory infection and upper respiratory bacterial infection.

    PubMed

    Xu, Qingfu; Wischmeyer, Jareth; Gonzalez, Eduardo; Pichichero, Michael E

    2017-07-01

    We sought to understand how polymicrobial colonization varies during health, viral upper respiratory infection (URI) and acute upper respiratory bacterial infection to understand differences in infection-prone vs. non-prone patients. Nasopharyngeal (NP) samples were collected from 74 acute otitis media (AOM) infection-prone and 754 non-prone children during 2094 healthy visits, 673 viral URI visits and 631 AOM visits. Three otopathogens Streptococcus pneumoniae (Spn), Nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis (Mcat) were identified by culture. NP colonization rates of multiple otopathogens during health were significantly lower than during viral URI, and during URI they were lower than at onset of upper respiratory bacterial infection in both AOM infection-prone and non-prone children. AOM infection-prone children had higher polymicrobial colonization rates than non-prone children during health, viral URI and AOM. Polymicrobial colonization rates of AOM infection-prone children during health were equivalent to that of non-prone children during viral URI, and during viral URI were equivalent to that of non-prone during AOM infection. Spn colonization was positively associated with NTHi and Mcat colonization during health, but negatively during AOM infection. The infection-prone patients more frequently have multiple potential bacterial pathogens in the NP than the non-prone patients. Polymicrobial interaction in the NP differs during health and at onset of infection. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  6. Rapid Dispersion of Polymicrobial Wound Biofilms with Depolymerase Enzymes

    DTIC Science & Technology

    2012-11-01

    and antimicrobial resistance vary greatly between pathogens associated with war wounds , one common trait shared by all is the ability to colonize...AD_________________ Award Number: W81XWH-11-2-0006 TITLE: Rapid Dispersion of Polymicrobial Wound ...TITLE AND SUBTITLE Rapid Dispersion of Polymicrobial Wound Biofilms with Depolymerase Enzymes 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-11

  7. Surgical treatment of culture-negative aortic infective endocarditis.

    PubMed

    Polat, Adil; Tuncer, Altug; Tuncer, Eylem Yayla; Mataraci, Ilker; Aksoy, Eray; Donmez, Arzu Antal; Balkanay, Mehmet; Zeybek, Rahmi; Yakut, Cevat

    2012-01-01

    We retrospectively analyzed the results of operations done for culture-negative aortic infective endocarditis at a single center over a period of 26 years. From June 1985 to January 2011, we operated on 82 patients with infective endocarditis of the aortic valve for which the results of culture were negative. Sixty-five of the patients (79.3%) were male and the patients' mean age was 38.0±14.4 years (range, 9 to 73 years). Nineteen of the patients (23.2%) had a history of previous cardiac surgery, and 16 of the patients (19.5%) had endocarditis of a prosthetic valve. Two patients (2.4%) had conduction blocks. The mean duration of follow-up was 7.1±4.3 years (range, 0.1 to 16.9 years), yielding a total of 477.0 patient-years for the study population. One hundred and thirty-eight procedures were done on the 82 patients in the study. The most common procedure was aortic valve replacement, which was done on 67 patients (81.7%). Thirty-nine patients (47.6%) had concomitant procedures done on the mitral valve. In-hospital death occurred in 14 patients (17.1%). Postoperatively, 17 patients (20.7%) had a low cardiac output and 9 patients (11.0%) had heart block, of whom 3 required implantation of a permanent pacemaker. The actuarial rate of survival of the patient population at 1, 5, 10, and 15 years was 92.5%±3.2%, 85.6%±4.5%, 82.5±5.3%, and 72.2±10.7% respectively. Culture-negative infective endocarditis is a major problem in the diagnosis and treatment of a significant proportion of cases of endocarditis. Most of the affected patients are in a healed state, which could be a cause of negative culture results. In-hospital mortality in patients with culture-negative infective aortic endocarditis is associated with a history of previous cardiac surgery, whereas long-term mortality in this patient population is associated with nonaortic procedures. Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  8. Culture-negative hand abscesses in immunocompetent individuals.

    PubMed

    Ho, Y M S; Sebastin, S J; Lim, A Y T

    2012-02-01

    Gonococcal infection is a common sexually-transmitted infection in the older male population in our local setting. It is caused by Neisseria gonorrhoeae, and results in fever, dysuria and a foul-smelling discharge from the external urethral meatus. Occasionally, it may also present with disseminated gonococcal infection - dermatitis, septic arthritis and even meningitis or endocarditis. We present two unusual cases, where the primary presentation was that of multiple subcutaneous hand and wrist abscesses. This illustrates the need for competent history-taking, especially in culture-negative patients. We also recommend the use of gonococcal polymerase chain reaction tests in patients who demonstrate negative routine cultures, or in lieu of gonococcal culture when the diagnosis is equivocal or urgently required.

  9. Polymicrobial Interactions: Impact on Pathogenesis and Human Disease

    PubMed Central

    Peters, Brian M.; Jabra-Rizk, Mary Ann; O'May, Graeme A.; Costerton, J. William

    2012-01-01

    Summary: Microorganisms coexist in a complex milieu of bacteria, fungi, archaea, and viruses on or within the human body, often as multifaceted polymicrobial biofilm communities at mucosal sites and on abiotic surfaces. Only recently have we begun to appreciate the complicated biofilm phenotype during infection; moreover, even less is known about the interactions that occur between microorganisms during polymicrobial growth and their implications in human disease. Therefore, this review focuses on polymicrobial biofilm-mediated infections and examines the contribution of bacterial-bacterial, bacterial-fungal, and bacterial-viral interactions during human infection and potential strategies for protection against such diseases. PMID:22232376

  10. Clinical Differences Between Monomicrobial and Polymicrobial Vertebral Osteomyelitis.

    PubMed

    Issa, Kimona; Pourtaheri, Sina; Stewart, Tyler; Faloon, Michael; Sahai, Nikhil; Mease, Samuel; Sinha, Kumar; Hwang, Ki; Emami, Arash

    2016-11-11

    Little literature exists examining differences in presentation and outcomes between monomicrobial and polymicrobial vertebral infections. Seventy-nine patients treated for vertebral osteomyelitis between 2001 and 2011 were reviewed. Patients were divided into monomicrobial and polymicrobial cohorts based on type of infection. Various characteristics were compared between the 2 groups. The 26 patients with a polymicrobial infection were older and had a higher mortality rate, lower clearance of infection, larger infection, more vertebral instability, higher erythrocyte sedimentation rate at presentation, and longer mean length of stay. There were no significant differences in Oswestry Disability Index scores at final follow-up, but there were differences in presentation and clinical outcomes between monomicrobial and polymicrobial vertebral osteomyelitis. Patients may benefit from counseling regarding their disease type and potential prognosis. [Orthopedics. 201x; xx(x):xx-xx.].

  11. Clinical utility of a polymerase chain reaction assay in culture-negative necrotizing otitis externa.

    PubMed

    Gruber, Maayan; Roitman, Ariel; Doweck, Ilana; Uri, Nechama; Shaked-Mishan, Pninit; Kolop-Feldman, Aharon; Cohen-Kerem, Raanan

    2015-04-01

    This study describes a subset of necrotizing otitis externa (NOE) patients with a refractory disease and negative cultures. In these cases, we decided to use a polymerase chain reaction (PCR) assay from surgically obtained tissue under sterile conditions to improve pathogen detection sensitivity. Retrospective case review. Academic medical center. Nineteen consecutive patients diagnosed with NOE between January 2008 and January 2014 inclusive. Three patients of this cohort presented a culture-negative disease. Diagnostic. Positive detection of pathogens using a PCR assay in cases with a complicated course of NOE and clinical resolution of the disease after targeted therapy according to PCR results. Surgical samples were obtained under sterile conditions from three patients with negative cultures and a refractory disease course of NOE. PCR assays were performed using pan-bacteria and pan-fungi protocols. In all three samples, a positive result for a fungal pathogen was recorded and followed by successful empirical targeted therapy. Patients who present with a refractory culture-negative NOE should be suspected as suffering from a fungal disease. The PCR assay may be an important laboratory adjunct in detecting pathogens responsible for NOE and can aid to promote therapy and disease resolution.

  12. Polymerase chain reaction detection of Kingella kingae in children with culture-negative septic arthritis in eastern Ontario

    PubMed Central

    Slinger, Robert; Moldovan, Ioana; Bowes, Jennifer; Chan, Francis

    2016-01-01

    BACKGROUND: The bacterium Kingella kingae may be an under-recognized cause of septic arthritis in Canadian children because it is difficult to grow in culture and best detected using molecular methods. OBJECTIVES: To determine whether K kingae is present in culture-negative joint fluid specimens from children in eastern Ontario using polymerase chain reaction (PCR) detection methods. METHODS: K kingae PCR testing was performed using residual bacterial culture-negative joint fluid collected from 2010 to 2013 at a children’s hospital in Ottawa, Ontario. The clinical features of children with infections caused by K kingae were compared with those of children with infections caused by the ‘typical’ septic arthritis bacteria, Staphylococcus aureus and Streptococcus pyogenes. RESULTS: A total of 50 joint fluid specimens were submitted over the study period. Ten were culture-positive, eight for S aureus and two for S pyogenes. Residual joint fluid was available for 27 of the 40 culture-negative specimens and K kingae was detected using PCR in seven (25.93%) of these samples. Children with K kingae were significantly younger (median age 1.7 versus 11.3 years; P=0.01) and had lower C-reactive protein levels (median 23.8 mg/L versus 117.6. mg/L; P=0.01) than those infected with other bacteria. CONCLUSIONS: K kingae was frequently detected using PCR in culture-negative joint fluid specimens from children in eastern Ontario. K kingae PCR testing of culture-negative joint samples in children appears to be warranted. PMID:27095882

  13. Polymicrobial outbreak of intermittent peritoneal dialysis peritonitis during external wall renovation at a dialysis center.

    PubMed

    Cheng, V C; Lo, W K; Woo, P C; Chan, S B; Cheng, S W; Ho, M; Yuen, K Y

    2001-01-01

    To investigate an outbreak of peritonitis in intermittent peritoneal dialysis (IPD) patients. An outbreak investigation was performed to identify the etiology of the polymicrobial outbreak, and a retrospective case-control study was conducted to assess the risk factors for development of peritonitis. Renal dialysis center. Ten episodes of peritonitis occurred in 8 of 61 patients over a 6-month period in which 669 IPD procedures were analyzed. Field visit to renal dialysis center to examine the entire IPD procedure, inspect the hospital environment, and perform air bacterial count. The environmental factors and risk factors contributing to the polymicrobial peritonitis outbreak in IPD patients. The incidence of IPD peritonitis was determined before and after interventions. The causative organisms included Acinetobacter baumanii (6), Stenotrophomonas maltophilia (2), Pseudomonas aeruginosa (1), Candida albicans (1), C. tropicalis (1), Enterococcus (3), and Enterobacteriaceae (2). Four episodes of peritonitis involved infection by more than one organism. Air sampling of the environment detected a median of 110 colony forming units of bacteria per cubic meter of air, 10% of which were found to be Acinetobacter baumanii. The source of this polymicrobial outbreak was attributed to the bamboo scaffolding structure covering the external wall of the hospital during renovation. A retrospective case-control study indicated that the absence of the flush-before-fill step was a risk factor for development of peritonitis. In addition to invasive aspergillosis in transplant or oncology patients, Acinetobacter peritonitis in dialysis patients should be considered another microbial cause of outbreak associated with hospital renovation.

  14. Evidence for polymicrobial communities in explanted vascular filters and atheroma debris.

    PubMed

    Ellis, Jeremy E; Heuser, Richard; Missan, Dara S; Martinez, Delyn; Heningburg, Avory; Shabilla, Matthew; Schwartz, Renata; Fry, Stephen

    2017-06-01

    Microbial communities have been implicated in a variety of disease processes and have been intermittently observed in arterial disease; however, no comprehensive unbiased community analysis has been performed. We hypothesize that complex microbial communities may be involved in chronic vascular diseases as well and may be effectively characterized by molecular assays. The main objective is to survey vascular debris, atheroma, and vascular filters for polymicrobial communities consisting of prokaryotic and eukaryotic microbes, specifically eukaryotic microbes. We examined vascular aspirates of atheromatous debris or embolic protection filters in addition to matched peripheral blood samples, from fifteen patients, as well as three cadaveric coronary arteries from two separate patients, for microbial communities. General fluorescence microscopy by Höechst and ethidium bromide DNA stains, prokaryotic and eukaryotic community analysis by Next Generation DNA Sequencing (NGS), and a eukaryotic microbial 9 probe multiplexed quantitative PCR were used to detect and characterize the presence of putative polymicrobial communities. No prokaryotes were detected in peripheral blood; however, in 4 of 9 sequenced filters and in 2 of 7 sequenced atheroma debris samples, prokaryotic populations were identified. By DNA sequencing, eukaryotic microbes were detected in 4 of 15 blood samples, 5 of the 9 sequenced filters, and 3 of the 7 atheroma debris samples. The quantitative multiplex PCR detected sequences consistent with eukaryotic microbes in all 9 analyzed filter samples as well as 5 of the 7 atheroma debris samples. Microscopy reveals putative polymicrobial communities within filters and atheroma debris. The main contributing prokaryotic species in atheroma debris suggest a diverse and novel composition. Additionally, Funneliformis mosseae, an arbuscular mycorrhizal fungus in the Glomeraceae family, was detected in the coronary hard plaque from two patients. Well studied

  15. Polymicrobial Infection with Major Periodontal Pathogens Induced Periodontal Disease and Aortic Atherosclerosis in Hyperlipidemic ApoEnull Mice

    PubMed Central

    Rivera, Mercedes F.; Lee, Ju-Youn; Aneja, Monika; Goswami, Vishalkant; Liu, Liying; Velsko, Irina M.; Chukkapalli, Sasanka S.; Bhattacharyya, Indraneel; Chen, Hao; Lucas, Alexandra R.; Kesavalu, Lakshmyya N.

    2013-01-01

    Periodontal disease (PD) and atherosclerosis are both polymicrobial and multifactorial and although observational studies supported the association, the causative relationship between these two diseases is not yet established. Polymicrobial infection-induced periodontal disease is postulated to accelerate atherosclerotic plaque growth by enhancing atherosclerotic risk factors of orally infected Apolipoprotein E deficient (ApoEnull) mice. At 16 weeks of infection, samples of blood, mandible, maxilla, aorta, heart, spleen, and liver were collected, analyzed for bacterial genomic DNA, immune response, inflammation, alveolar bone loss, serum inflammatory marker, atherosclerosis risk factors, and aortic atherosclerosis. PCR analysis of polymicrobial-infected (Porphyromonas gingivalis [P. gingivalis], Treponema denticola [T. denticola], and Tannerella forsythia [T. forsythia]) mice resulted in detection of bacterial genomic DNA in oral plaque samples indicating colonization of the oral cavity by all three species. Fluorescent in situ hybridization detected P. gingivalis and T. denticola within gingival tissues of infected mice and morphometric analysis showed an increase in palatal alveolar bone loss (p<0.0001) and intrabony defects suggesting development of periodontal disease in this model. Polymicrobial-infected mice also showed an increase in aortic plaque area (p<0.05) with macrophage accumulation, enhanced serum amyloid A, and increased serum cholesterol and triglycerides. A systemic infection was indicated by the detection of bacterial genomic DNA in the aorta and liver of infected mice and elevated levels of bacterial specific IgG antibodies (p<0.0001). This study was a unique effort to understand the effects of a polymicrobial infection with P. gingivalis, T. denticola and T. forsythia on periodontal disease and associated atherosclerosis in ApoEnull mice. PMID:23451182

  16. Polymicrobial Biofilm Studies: From Basic Science to Biofilm Control

    PubMed Central

    Willems, Hubertine ME; Xu, Zhenbo; Peters, Brian M

    2016-01-01

    Microbes rarely exist as single species planktonic forms as they have been commonly studied in the laboratory. Instead, the vast majority exists as part of complex polymicrobial biofilm communities attached to host and environmental surfaces. The oral cavity represents one of the most diverse and well-studied polymicrobial consortia. Despite a burgeoning field of mechanistic biofilm research within the past decades, our understanding of interactions that occur between microbial members within oral biofilms is still limited. Thus, the primary objective of this review is to focus on polymicrobial biofilm formation, microbial interactions and signaling events that mediate oral biofilm development, consequences of oral hygiene on both local and systemic disease, and potential therapeutic strategies to limit oral dysbiosis. PMID:27134811

  17. Bartonella spp. and Coxiella burnetii Associated with Community-Acquired, Culture-Negative Endocarditis, Brazil

    PubMed Central

    Castelli, Jussara Bianchi; Mansur, Alfredo Jose; Pereira dos Santos, Fabiana; Colombo, Silvia; do Nascimento, Elvira Mendes; Paddock, Christopher D.; Brasil, Roosecelis Araújo; Velho, Paulo Eduardo Neves Ferreira; Drummond, Marina Rovani; Grinberg, Max; Strabelli, Tania Mara Varejao

    2015-01-01

    We evaluated culture-negative, community-acquired endocarditis by using indirect immunofluorescent assays and molecular analyses for Bartonella spp. and Coxiella burnetii and found a prevalence of 19.6% and 7.8%, respectively. Our findings reinforce the need to study these organisms in patients with culture-negative, community-acquired endocarditis, especially B. henselae in cat owners. PMID:26197233

  18. Distinct polymicrobial populations in a chronic foot ulcer with implications for diagnostics and anti-infective therapy

    PubMed Central

    2014-01-01

    Background Polymicrobial infections caused by combinations of different bacteria are being detected with an increasing frequency. The evidence of such complex infections is being revealed through the use of novel molecular and culture-independent methods. Considerable progress has been made in the last decade regarding the diagnostic application of such molecular techniques. In particular, 16S rDNA-based sequencing and even metagenomic analyses have been successfully used to study the microbial diversity in ecosystems and human microbiota. Here, we utilized denaturing high-performance liquid chromatography (DHPLC) as a diagnostic tool for identifying different bacterial species in complex clinical samples of a patient with a chronic foot ulcer. Case presentation A 45-year-old female suffered from a chronic 5x5cm large plantar ulcer located in the posterior calcaneal area with subcutaneous tissue infection and osteomyelitis. The chronic ulcer developed over a period of 8 years. Culture and DHPLC revealed a distinct and location-dependent polymicrobial infection of the ulcer. The analysis of a superficial biopsy revealed a mixture of Staphylococcus aureus, Proteus vulgaris, and Fusobacterium nucleatum, whereas the tissue-deep biopsy harbored a mixture of four different bacterial species, namely Gemella morbillorum, Porphyromonas asaccharolytica, Bacteroides fragilis, and Arcanobacterium haemolyticum. Conclusions This clinical case highlights the difficulties in assessing polymicrobial infections where a mixture of fastidious, rapid and slow growing bacteria as well as anaerobes exists as structured communities within the tissue architecture of chronic wound infections. The diagnosis of this multilayered polymicrobial infection led to a microbe-adapted antibiotic therapy, targeting the polymicrobial nature of this infection in addition to a standard local wound treatment. However, a complete wound closure could not be achieved due to the long-lasting extensive

  19. Community surveillance enhances Pseudomonas aeruginosa virulence during polymicrobial infection.

    PubMed

    Korgaonkar, Aishwarya; Trivedi, Urvish; Rumbaugh, Kendra P; Whiteley, Marvin

    2013-01-15

    Most infections result from colonization by more than one microbe. Within such polymicrobial infections, microbes often display synergistic interactions that result in increased disease severity. Although many clinical studies have documented the occurrence of synergy in polymicrobial infections, little is known about the underlying molecular mechanisms. A prominent pathogen in many polymicrobial infections is Pseudomonas aeruginosa, a Gram-negative bacterium that displays enhanced virulence during coculture with Gram-positive bacteria. In this study we discovered that during coinfection, P. aeruginosa uses peptidoglycan shed by Gram-positive bacteria as a cue to stimulate production of multiple extracellular factors that possess lytic activity against prokaryotic and eukaryotic cells. Consequently, P. aeruginosa displays enhanced virulence in a Drosophila model of infection when cocultured with Gram-positive bacteria. Inactivation of a gene (PA0601) required for peptidoglycan sensing mitigated this phenotype. Using Drosophila and murine models of infection, we also show that peptidoglycan sensing results in P. aeruginosa-mediated reduction in the Gram-positive flora in the infection site. Our data suggest that P. aeruginosa has evolved a mechanism to survey the microbial community and respond to Gram-positive produced peptidoglycan through production of antimicrobials and toxins that not only modify the composition of the community but also enhance host killing. Additionally, our results suggest that therapeutic strategies targeting Gram-positive bacteria might be a viable approach for reducing the severity of P. aeruginosa polymicrobial infections.

  20. A case of culture-negative endocarditis due to Streptococcus tigurinus.

    PubMed

    Kanamori, Hajime; Kakuta, Risako; Yano, Hisakazu; Suzuki, Tomoyuki; Gu, Yoshiaki; Oe, Chihiro; Inomata, Shinya; Aoyagi, Tetsuji; Hatta, Masumitsu; Endo, Shiro; Tokuda, Koichi; Weber, David J; Nakamura, Yasuhiro; Saiki, Yoshikatsu; Kaku, Mitsuo

    2015-02-01

    Culture-negative endocarditis remains a diagnostic and therapeutic challenge despite recent medical advances. Streptococcus tigurinus, a novel member of the Streptococcus mitis group, was first identified in Zurich. S. tigurinus possesses virulence determinants and causes invasive infections. We report a case of culture-negative endocarditis with serious complications due to S. tigurinus, which was identified by 16S ribosomal RNA gene sequence analysis of excised valve tissue specimens. This technique is useful for identification of the causative microorganism in patients with culture-negative endocarditis and may facilitate early diagnosis and appropriate antimicrobial treatment.

  1. Presence of a polymicrobial endometrial biofilm in patients with bacterial vaginosis.

    PubMed

    Swidsinski, Alexander; Verstraelen, Hans; Loening-Baucke, Vera; Swidsinski, Sonja; Mendling, Werner; Halwani, Zaher

    2013-01-01

    To assess whether the bacterial vaginosis biofilm extends into the upper female genital tract. Endometrial samples obtained during curettage and fallopian tube samples obtained during salpingectomy were collected. Endometrial and fallopian tube samples were analyzed for the presence of bacteria with fluorescence-in-situ-hybridisation (FISH) analysis with probes targeting bacterial vaginosis-associated and other bacteria. A structured polymicrobial Gardnerella vaginalis biofilm could be detected in part of the endometrial and fallopian tube specimens. Women with bacterial vaginosis had a 50.0% (95% CI 24.0-76.0) risk of presenting with an endometrial Gardnerella vaginalis biofilm. Pregnancy (AOR  = 41.5, 95% CI 5.0-341.9, p<0.001) and the presence of bacterial vaginosis (AOR  = 23.2, 95% CI 2.6-205.9, p<0.001) were highly predictive of the presence of uterine or fallopian bacterial colonisation when compared to non-pregnant women without bacterial vaginosis. Bacterial vaginosis is frequently associated with the presence of a structured polymicrobial Gardnerella vaginalis biofilm attached to the endometrium. This may have major implications for our understanding of the pathogenesis of adverse pregnancy outcome in association with bacterial vaginosis.

  2. Presence of a Polymicrobial Endometrial Biofilm in Patients with Bacterial Vaginosis

    PubMed Central

    Loening-Baucke, Vera; Swidsinski, Sonja; Mendling, Werner; Halwani, Zaher

    2013-01-01

    Objective To assess whether the bacterial vaginosis biofilm extends into the upper female genital tract. Study Design Endometrial samples obtained during curettage and fallopian tube samples obtained during salpingectomy were collected. Endometrial and fallopian tube samples were analyzed for the presence of bacteria with fluorescence-in-situ-hybridisation (FISH) analysis with probes targeting bacterial vaginosis-associated and other bacteria. Results A structured polymicrobial Gardnerella vaginalis biofilm could be detected in part of the endometrial and fallopian tube specimens. Women with bacterial vaginosis had a 50.0% (95% CI 24.0–76.0) risk of presenting with an endometrial Gardnerella vaginalis biofilm. Pregnancy (AOR  = 41.5, 95% CI 5.0–341.9, p<0.001) and the presence of bacterial vaginosis (AOR  = 23.2, 95% CI 2.6–205.9, p<0.001) were highly predictive of the presence of uterine or fallopian bacterial colonisation when compared to non-pregnant women without bacterial vaginosis. Conclusion Bacterial vaginosis is frequently associated with the presence of a structured polymicrobial Gardnerella vaginalis biofilm attached to the endometrium. This may have major implications for our understanding of the pathogenesis of adverse pregnancy outcome in association with bacterial vaginosis. PMID:23320114

  3. Necrotizing ANCA-Positive Glomerulonephritis Secondary to Culture-Negative Endocarditis

    PubMed Central

    Van Haare Heijmeijer, Sophie; Wilmes, Dunja; Aydin, Selda; Clerckx, Caroline; Labriola, Laura

    2015-01-01

    Infective endocarditis (IE) and small-vessel vasculitis may have similar clinical features, including glomerulonephritis. Furthermore the association between IE and ANCA positivity is well documented, making differential diagnosis between IE- and ANCA-associated vasculitis particularly difficult, especially in case of culture-negative IE. We report on one patient with glomerulonephritis secondary to culture-negative IE caused by Bartonella henselae which illustrates this diagnostic difficulty. PMID:26819786

  4. Polymicrobial Candida biofilms: friends and foe in the oral cavity.

    PubMed

    O'Donnell, Lindsay E; Millhouse, Emma; Sherry, Leighann; Kean, Ryan; Malcolm, Jennifer; Nile, Christopher J; Ramage, Gordon

    2015-11-01

    The role of polymicrobial biofilm infections in medicine is becoming more apparent. Increasing number of microbiome studies and deep sequencing has enabled us to develop a greater understanding of how positive and negative microbial interactions influence disease outcomes. An environment where this is particularly pertinent is within the oral cavity, a rich and diverse ecosystem inhabited by both bacteria and yeasts, which collectively occupy and coexist within various niches as biofilm communities. Studies within this environment have however tended to be subject to extensive independent investigation, in the context of either polymicrobial bacterial communities or yeast biofilms, but rarely both together. It is clear however that they are not mutually exclusive. Therefore, this review aims to explore the influence of candidal populations on the composition of these complex aggregates and biofilm communities, to investigate their mechanistic interactions to understand how these impact clinical outcomes, and determine whether we can translate how this knowledge can be used to improve patient management.

  5. Importance of Candida-bacterial polymicrobial biofilms in disease

    PubMed Central

    Harriott, Melphine M.; Noverr, Mairi C.

    2011-01-01

    Candida albicans is the most prevalent human fungal pathogen, with an ability to inhabit diverse host niches and cause disease in both immunocompetent and immunocompromised individuals. C. albicans also readily forms biofilms on indwelling medical devices and mucosal tissues, which serve as an infectious reservoir that is difficult to eradicate, and can lead to lethal systemic infections. Biofilm formation occurs within a complex milieu of host factors and other members of the human microbiota. Polymicrobial interactions will likely dictate the cellular and biochemical composition of the biofilm, as well as influence clinically relevant outcomes such as drug and host resistance and virulence. In this manuscript, we review C. albicans infections in the context of in vivo polymicrobial biofilms and implications for pathogenesis. PMID:21855346

  6. Reduced Expression of SARM in Mouse Spleen during Polymicrobial Sepsis.

    PubMed

    Gong, Yu; Zou, Lin; Cen, Dongzhi; Chao, Wei; Chen, Dunjin

    2016-12-01

    Objective Immune dysfunction, including prominent apoptosis of immune cells and decreased functioning of the remaining immune cells, plays a central role in the pathogenesis of sepsis. Sterile α and HEAT/armadillo motif-containing protein (SARM) is implicated in the regulation of immune cell apoptosis. This study aimed to elucidate SARM contributes to sepsis-induced immune cell death and immunosuppression. Methods A mouse model of polymicrobial sepsis was generated by cecum ligation and puncture (CLP). SARM gene and protein expression, caspase 3 cleavage and intracellular ATP production were measured in the mouse spleens. Results CLP-induced polymicrobial sepsis specifically attenuated both the gene and protein expression of SARM in the spleens. Moreover, the attenuation of SARM expression synchronized with splenocyte apoptosis, as evidenced by increased caspase 3 cleavage and ATP depletion. Conclusions These findings suggest that SARM is a potential regulator of sepsis-induced splenocyte apoptosis.

  7. Impact of Staphylococcus aureus on Pathogenesis in Polymicrobial Infections

    PubMed Central

    Nair, Nisha; Biswas, Raja; Götz, Friedrich

    2014-01-01

    Polymicrobial infections involving Staphylococcus aureus exhibit enhanced disease severity and morbidity. We reviewed the nature of polymicrobial interactions between S. aureus and other bacterial, fungal, and viral cocolonizers. Microbes that were frequently recovered from the infection site with S. aureus are Haemophilus influenzae, Enterococcus faecalis, Pseudomonas aeruginosa, Streptococcus pneumoniae, Corynebacterium sp., Lactobacillus sp., Candida albicans, and influenza virus. Detailed analyses of several in vitro and in vivo observations demonstrate that S. aureus exhibits cooperative relations with C. albicans, E. faecalis, H. influenzae, and influenza virus and competitive relations with P. aeruginosa, Streptococcus pneumoniae, Lactobacillus sp., and Corynebacterium sp. Interactions of both types influence changes in S. aureus that alter its characteristics in terms of colony formation, protein expression, pathogenicity, and antibiotic susceptibility. PMID:24643542

  8. Assessment of sputum smear-positive but culture-negative results among newly diagnosed pulmonary tuberculosis patients in Tanzania.

    PubMed

    Mnyambwa, Nicholaus Peter; Ngadaya, Esther S; Kimaro, Godfather; Kim, Dong-Jin; Kazwala, Rudovick; Petrucka, Pammla; Mfinanga, Sayoki G

    2017-01-01

    Diagnosis of pulmonary tuberculosis (TB) in technology-limited countries is widely achieved by smear microscopy, which has limited sensitivity and specificity. The frequency and clinical implication of smear-positive but culture-negative among presumptive TB patients remains unclear. A cross-sectional substudy was conducted which aimed to identify the proportion of nontuberculous mycobacteria (NTM) infections among 94 "smear-positive culture-negative" patients diagnosed between January 2013 and June 2016 in selected health facilities in Tanzania. Out of 94 sputa, 25 (26.60%) were GeneXpert® mycobacteria TB positive and 11/94 (11.70%) repeat-culture positive; 5 were Capilia TB-Neo positive and confirmed by GenoType MTBC to be Mycobacterium tuberculosis/Mycobacterium canettii. The remaining 6 Capilia TB-Neo negative samples were genotyped by GenoType® CM/AS, identifying 3 (3.19%) NTM, 2 Gram positive bacteria, and 1 isolate testing negative, together, making a total of 6/94 (6.38%) confirmed false smear-positives. Twenty-eight (29.79%) were confirmed TB cases, while 60 (63.83%) remained unconfirmed cases. Out of 6 (6.38%) patients who were HIV positive, 2 patients were possibly coinfected with mycobacteria. The isolation of NTM and other bacteria among smear-positive culture-negative samples and the presence of over two third of unconfirmed TB cases emphasize the need of both advanced differential TB diagnostic techniques and good clinical laboratory practices to avoid unnecessary administration of anti-TB drugs.

  9. Delayed emergency myelopoiesis following polymicrobial sepsis in neonates.

    PubMed

    Cuenca, Alex G; Cuenca, Angela L; Gentile, Lori F; Efron, Philip A; Islam, Saleem; Moldawer, Lyle L; Kays, David W; Larson, Shawn D

    2015-05-01

    Neonates have increased susceptibility to infection, which leads to increased mortality. Whether or not this as a result of implicit deficits in neonatal innate immune function or recapitulation of innate immune effector cell populations following infection is unknown. Here, we examine the process of emergency myelopoiesis whereby the host repopulates peripheral myeloid cells lost following the initial infectious insult. As early inflammatory responses are often dependent upon NF-κB and type I IFN signaling, we also examined whether the absence of MyD88, TRIF or MyD88 and TRIF signaling altered the myelopoietic response in neonates to polymicrobial sepsis. Following neonatal polymicrobial septic challenge, hematopoietic stem cell (HSC) expansion in bone marrow and the spleen were both attenuated and delayed in neonates compared with adults. Similar reductions in other precursors were observed in neonates. Similar to adult studies, the expansion of progenitor stem cell populations was also seen in the absence of MyD88 and/or TRIF signaling. Overall, neonates have impaired emergency myelopoiesis in response to sepsis compared with young adults. Despite reports that this expansion may be related to TLR signaling, our data suggest that other factors may be important, as TRIF(-/-) and MyD88(-/-) neonatal HSCs are still able to expand in response to polymicrobial neonatal sepsis. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  10. Isolation of bacterial DNA followed by sequencing and differing cytokine response in peritoneal dialysis effluent help in identifying bacteria in culture negative peritonitis.

    PubMed

    Prasad, Narayan; Singh, Kamini; Gupta, Amit; Prasad, Kashi Nath

    2016-11-16

    The treatment of peritoneal dialysis related culture negative peritonitis is empirical which increases the cost of therapy and moreover antibiotic resistance. We aimed the study to isolate bacterial DNA from PD effluent and indentify bacteria causing peritonitis in culture negative situations. We have also studied the cytokine response with different bacteria causing peritonitis. We have isolated bacterial DNA from PD effluent of culture negative and culture positive peritonitis patients. Bacterial DNA was subjected to polymerase chain reaction using universal bacteria specific primers and subsequently to Gram type specific primers for the differentiation of the etiologic agents into Gram positive and Gram negative. The amplified products were sequenced and subjected to blast search to identify agent at genus/ species level. Of the 30 molecular method positive samples, 16 (53.33%) samples were positive for Gram negative bacteria and 4 (13.33%) for Gram positive while remaining10 (33.33%) were positive for both Gram positive and Gram negative bacteria. We have found organisms which usually do not grow on normal culture methods. TNF- α was significantly associated with Gram positive peritonitis and regulatory cytokine IL-10 with Gram negative peritonitis. The molecular techniques are helpful in detecting and identifying organisms from culture negative PD effluent. This article is protected by copyright. All rights reserved.

  11. Distinct interacting core taxa in co-occurrence networks enable discrimination of polymicrobial oral diseases with similar symptoms

    PubMed Central

    Shiba, Takahiko; Watanabe, Takayasu; Kachi, Hirokazu; Koyanagi, Tatsuro; Maruyama, Noriko; Murase, Kazunori; Takeuchi, Yasuo; Maruyama, Fumito; Izumi, Yuichi; Nakagawa, Ichiro

    2016-01-01

    Polymicrobial diseases, which can be life threatening, are caused by the presence and interactions of multiple microbes. Peri-implantitis and periodontitis are representative polymicrobial diseases that show similar clinical symptoms. To establish a means of differentiating between them, we compared microbial species and functional genes in situ by performing metatranscriptomic analyses of peri-implantitis and periodontitis samples obtained from the same subjects (n = 12 each). Although the two diseases differed in terms of 16S rRNA-based taxonomic profiles, they showed similarities with respect to functional genes and taxonomic and virulence factor mRNA profiles. The latter—defined as microbial virulence types—differed from those of healthy periodontal sites. We also showed that networks based on co-occurrence relationships of taxonomic mRNA abundance (co-occurrence networks) were dissimilar between the two diseases. Remarkably, these networks consisted mainly of taxa with a high relative mRNA-to-rRNA ratio, with some showing significant co-occurrence defined as interacting core taxa, highlighting differences between the two groups. Thus, peri-implantitis and periodontitis have shared as well as distinct microbiological characteristics. Our findings provide insight into microbial interactions in polymicrobial diseases with unknown etiologies. PMID:27499042

  12. Characteristics and outcomes of culture-negative versus culture-positive severe sepsis

    PubMed Central

    2013-01-01

    Introduction Culture-negative sepsis is a common but relatively understudied condition. The aim of this study was to compare the characteristics and outcomes of culture-negative versus culture-positive severe sepsis. Methods This was a prospective observational cohort study of 1001 patients who were admitted to the medical intensive care unit (ICU) of a university hospital from 2004 to 2009 with severe sepsis. Patients with documented fungal, viral, and parasitic infections were excluded. Results There were 415 culture-negative patients (41.5%) and 586 culture-positive patients (58.5%). Gram-positive bacteria were isolated in 257 patients, and gram-negative bacteria in 390 patients. Culture-negative patients were more often women and had fewer comorbidities, less tachycardia, higher blood pressure, lower procalcitonin levels, lower Acute Physiology and Chronic Health Evaluation II (median 25.0 (interquartile range 19.0 to 32.0) versus 27.0 (21.0 to 33.0), P = 0.001) and Sequential Organ Failure Assessment scores, less cardiovascular, central nervous system, and coagulation failures, and less need for vasoactive agents than culture-positive patients. The lungs were a more common site of infection, while urinary tract, soft tissue and skin infections, infective endocarditis and primary bacteremia were less common in culture-negative than in culture-positive patients. Culture-negative patients had a shorter duration of hospital stay (12 days (7.0 to 21.0) versus 15.0 (7.0 to27.0), P = 0.02) and lower ICU mortality than culture-positive patients. Hospital mortality was lower in the culture-negative group (35.9%) than in the culture-positive group (44.0%, P = 0.01), the culture-positive subgroup, which received early appropriate antibiotics (41.9%, P = 0.11), and the culture-positive subgroup, which did not (55.5%, P < 0.001). After adjusting for covariates, culture positivity was not independently associated with mortality on multivariable analysis. Conclusions

  13. Occult polymicrobial endocarditis with Haemophilus parainfluenzae in intravenous drug abusers.

    PubMed

    Raucher, B; Dobkin, J; Mandel, L; Edberg, S; Levi, M; Miller, M

    1989-02-01

    Fewer than 8 percent of intravenous drug abusers are found to have polymicrobial endocarditis. We report on cases of occult polymicrobial infective endocarditis with Haemophilus parainfluenzae in 10 intravenous drug abusers. Clinical and laboratory data on all 10 patients were obtained from hospital charts, and information on illicit drug use methods was given by five patients. Blood cultures were performed, as well as susceptibility testing to antibiotics. Subsequent molecular epidemiologic studies were performed on selected Staphylococcus aureus and H. parainfluenzae strains. Phage typing of S. aureus and biotyping of H. parainfluenzae strains were also done. Results of the initial blood cultures were positive on the second to fifth days (mean, 2.6 days), demonstrating a gram-positive pathogen in nine patients and Bacteroides asaccharolyticus in one. Significantly, in each case, H. parainfluenzae alone was subsequently identified from additional blood cultures, with a mean delay of 20.4 days (range, five to 57 days) to the isolation of this organism. Epidemiologic data indicated that our cases did not represent a point-source outbreak. Antibiotic therapy uniformly failed until an agent active against H. parainfluenzae was added. The constellation of clinical, microbiologic, and epidemiologic findings was similar, and permitted prospective diagnosis and therapy in three patients. Despite the absence of S. aureus bacteremia in four, all 10 patients had right-sided endocarditis with septic pulmonary emboli. Five patients had initial blood cultures that were positive for two facultative gram-positive cocci (S. aureus and commensal oral streptococcal species). Our findings suggest that polymicrobial endocarditis with H. parainfluenzae in intravenous drug abusers is a distinct clinical syndrome, and should be considered in all patients if the response to appropriate antibiotics is atypical or if pulmonary emboli continue with therapy.

  14. Molecular Detection of Campylobacter jejuni as a Cause of Culture-Negative Spondylodiscitis

    PubMed Central

    Schulze, Marco H.; Oesterlein, Anett; Abele-Horn, Marianne; Baron, Stefan; Durchholz, Daniel; Langen, Heinz-Jakob; Jany, Berthold; Schoen, Christoph

    2012-01-01

    Spondylodiscitis caused by Campylobacter species is a rare disease which is most often caused by Campylobacter fetus. We report a case of culture-negative spondylodiscitis and a psoas abscess due to Campylobacter jejuni in a 68-year-old woman, as revealed by 16S rRNA gene and Campylobacter-specific PCRs from biopsied tissue. PMID:22259199

  15. Multiplex Pathogen Identification for Polymicrobial Urinary Tract Infections Using Biosensor Technology: A Prospective Clinical Study

    PubMed Central

    Mach, Kathleen E.; Du, Christine B.; Phull, Hardeep; Haake, David A.; Shih, Mei-Chiung; Baron, Ellen Jo; Liao, Joseph C.

    2014-01-01

    Purpose Rapid diagnosis of urinary tract infection would have a significant beneficial impact on clinical management, particularly in patients with structural or functional urinary tract abnormalities who are highly susceptible to recurrent polymicrobial infections. We examined the analytical validity of an electrochemical biosensor array for rapid molecular diagnosis of urinary tract infection in a prospective clinical study in patients with neurogenic bladder. Materials and Methods The electrochemical biosensor array was functionalized with DNA probes against 16S rRNA of the most common uropathogens. Spinal cord injured patients at a Veterans Affairs hospital were recruited into the study. Urine samples were generally tested on the biosensor within 1 to 2 hours of collection. Biosensor results were compared with those obtained using standard clinical microbiology laboratory methods. Results We successfully developed a 1-hour biosensor assay for multiplex identification of pathogens. From July 2007 to December 2008 we recruited 116 patients, yielding a total of 109 urine samples suitable for analysis and comparison between biosensor assay and standard urine culture. Of the samples 74% were positive, of which 42% were polymicrobial. We identified 20 organisms, of which Escherichia coli, Pseudomonas aeruginosa and Enterococcus species were the most common. Biosensor assay specificity and positive predictive value were 100%. Pathogen detection sensitivity was 89%, yielding a 76% negative predictive value. Conclusions To our knowledge we report the first prospective clinical study to successfully identify pathogens within a point of care time frame using an electrochemical biosensor platform. Additional efforts to improve the limit of detection and probe design are needed to further enhance assay sensitivity. PMID:19837423

  16. Etiology of bacterial vaginosis and polymicrobial biofilm formation.

    PubMed

    Jung, Hyun-Sul; Ehlers, Marthie M; Lombaard, Hennie; Redelinghuys, Mathys J; Kock, Marleen M

    2017-03-30

    Microorganisms in nature rarely exist in a planktonic form, but in the form of biofilms. Biofilms have been identified as the cause of many chronic and persistent infections and have been implicated in the etiology of bacterial vaginosis (BV). Bacterial vaginosis is the most common form of vaginal infection in women of reproductive age. Similar to other biofilm infections, BV biofilms protect the BV-related bacteria against antibiotics and cause recurrent BV. In this review, an overview of BV-related bacteria, conceptual models and the stages involved in the polymicrobial BV biofilm formation will be discussed.

  17. A case of polymicrobial infective endocarditis involving Neisseria mucosa occurring in an intravenous drug abuser.

    PubMed

    Giles, M W; Andrew, J H; Tellus, M M

    1988-12-01

    The incidence of polymicrobial endocarditis has increased markedly in recent years, in association with the increasing level of abuse of intravenous drugs. Neisseria mucosa, an upper respiratory tract commensal, is a rare cause of infective endocarditis. We report the first case of polymicrobial infective endocarditis involving Neisseria mucosa occurring in an intravenous drug abuser.

  18. Detecting the presence of bacterial DNA by PCR can be useful in diagnosing culture-negative cases of infection, especially in patients with suspected infection and antibiotic therapy.

    PubMed

    Lleo, Maria M; Ghidini, Valentina; Tafi, Maria Carla; Castellani, Francesco; Trento, Ilaria; Boaretti, Marzia

    2014-05-01

    Failing in bacteria isolation in a significant number of infections might be due to the involvement of microorganisms nonrecoverable in culture media. The presence cannot be ruled out of nondividing cells or even bacterial products still capable of promoting a host immunological response. Antibiotic therapy, for example, might induce a block of bacterial division and the impossibility of recovering cells in culture media. In these cases, a molecular method targeting DNA should be used. In this study, 230 clinical samples with a culture-negative report obtained from 182 patients were examined with a protocol of PCR targeting the bacterial 16S rRNA gene to evaluate the usefulness of molecular methods in differencing culture-negative infections from other pathologies. Amplicons were obtained in 14% of the samples, although this percentage increased (27%) in a subgroup of patients with presumptive diagnosis of infection and ongoing antibiotic therapy. By multiplex PCR, it was shown that detected DNA belonged mostly to Enterobacteriaceae and enterococcal species. Multiple culture-negative, PCR-positive samples and isolation of the same bacterial species in culture in additional samples from the same patient support the clinical significance of the data obtained and highlight the complementary role and usefulness of applying molecular methods in diagnostic microbiology. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  19. Polymicrobial Infections In Brain Tissue From Alzheimer's Disease Patients.

    PubMed

    Pisa, Diana; Alonso, Ruth; Fernández-Fernández, Ana M; Rábano, Alberto; Carrasco, Luis

    2017-07-17

    Several studies have advanced the idea that the etiology of Alzheimer's disease (AD) could be microbial in origin. In the present study, we tested the possibility that polymicrobial infections exist in tissue from the entorhinal cortex/hippocampus region of patients with AD using immunohistochemistry (confocal laser scanning microscopy) and highly sensitive (nested) PCR. We found no evidence for expression of early (ICP0) or late (ICP5) proteins of herpes simplex virus type 1 (HSV-1) in brain sections. A polyclonal antibody against Borrelia detected structures that appeared not related to spirochetes, but rather to fungi. These structures were not found with a monoclonal antibody. Also, Borrelia DNA was undetectable by nested PCR in the ten patients analyzed. By contrast, two independent Chlamydophila antibodies revealed several structures that resembled fungal cells and hyphae, and prokaryotic cells, but most probably were unrelated to Chlamydophila spp. Finally, several structures that could belong to fungi or prokaryotes were detected using peptidoglycan and Clostridium antibodies, and PCR analysis revealed the presence of several bacteria in frozen brain tissue from AD patients. Thus, our results show that polymicrobial infections consisting of fungi and bacteria can be revealed in brain tissue from AD patients.

  20. Noisy neighbourhoods: quorum sensing in fungal-polymicrobial infections.

    PubMed

    Dixon, Emily F; Hall, Rebecca A

    2015-10-01

    Quorum sensing was once considered a way in which a species was able to sense its cell density and regulate gene expression accordingly. However, it is now becoming apparent that multiple microbes can sense particular quorum-sensing molecules, enabling them to sense and respond to other microbes in their neighbourhood. Such interactions are significant within the context of polymicrobial disease, in which the competition or cooperation of microbes can alter disease progression. Fungi comprise a small but important component of the human microbiome and are in constant contact with bacteria and viruses. The discovery of quorum-sensing pathways in fungi has led to the characterization of a number of interkingdom quorum-sensing interactions. Here, we review the recent developments in quorum sensing in medically important fungi, and the implications these interactions have on the host's innate immune response.

  1. Noisy neighbourhoods: quorum sensing in fungal–polymicrobial infections

    PubMed Central

    Dixon, Emily F.

    2015-01-01

    Summary Quorum sensing was once considered a way in which a species was able to sense its cell density and regulate gene expression accordingly. However, it is now becoming apparent that multiple microbes can sense particular quorum‐sensing molecules, enabling them to sense and respond to other microbes in their neighbourhood. Such interactions are significant within the context of polymicrobial disease, in which the competition or cooperation of microbes can alter disease progression. Fungi comprise a small but important component of the human microbiome and are in constant contact with bacteria and viruses. The discovery of quorum‐sensing pathways in fungi has led to the characterization of a number of interkingdom quorum‐sensing interactions. Here, we review the recent developments in quorum sensing in medically important fungi, and the implications these interactions have on the host's innate immune response. PMID:26243526

  2. Revealing the dynamics of polymicrobial infections: implications for antibiotic therapy

    PubMed Central

    Rogers, Geraint B.; Hoffman, Lucas R.; Whiteley, Marvin; Daniels, Thomas W.V.; Carroll, Mary P.; Bruce, Kenneth D.

    2011-01-01

    As a new generation of culture-independent analytical strategies emerge, the amount of data on polymicrobial infections will increase dramatically. For these data to inform clinical thinking, and in turn to maximise benefits for patients, an appropriate framework for their interpretation is required. Here, we use cystic fibrosis (CF) lower airway infections as a model system to examine how conceptual and technological advances can address two clinical questions that are central to improved management of CF respiratory disease. Firstly, can markers of the microbial community be identified that predict a change in infection dynamics and clinical outcomes? Secondly, can these new strategies directly characterize the impact of antimicrobial therapies, allowing treatment efficacy to be both assessed and optimized? PMID:20554204

  3. Culture-negative infective endocarditis of the aortic valve due to Aerococcus urinae: a rare aetiology.

    PubMed

    Alozie, Anthony; Yerebakan, Can; Westphal, Bernd; Steinhoff, Gustav; Podbielski, Andreas

    2012-04-01

    Bacteria of the species Aerococcus urinae are Gram-positive, catalase-negative cocci that are arranged in pairs, tetrads, or clusters resembling enterococci or staphylococci. They are rare causative agents of infective endocarditis. Repetitive urinary tract infections based upon underlying genitourinary tract abnormalities could involve these bacteria. Due to their similarity to other Gram-positive cocci misinterpretation may occur along the line of microbiologic differentiation, which could potentially lead to a fatal outcome. We herein report on the clinical course of a 68 year-old male patient who in the setting of an embolic stroke was initially diagnosed with a culture-negative acute infective endocarditis of the aortic valve.

  4. A Case of Progressive Tubulo-Interstitial Nephritis due to Culture-negative Renal Tuberculosis.

    PubMed

    El-Reshaid, K A; Madda, J P; Al-Saleh, M A

    2001-01-01

    This report describes a woman with progressive renal failure without proteinuria, urinary obstruction or overt systemic disease. The progressive renal disease without pelvicalyceal deformities in the left kidney was not consistent with the vesicoureteric reflux nephropathy. A needle biopsy of the left kidney showed interstitial caseating granulomata. The patient did not have clinical, radiological or urine culture evidence of renal tuberculosis. She improved after treatment with antituberculous therapy. This case report demonstrates the value of kidney biopsy in establishing the diagnosis of such common and treatable disease even if clinically silent and urine culture negative.

  5. Pseudomonas aeruginosa Can Be Detected in a Polymicrobial Competition Model Using Impedance Spectroscopy with a Novel Biosensor

    PubMed Central

    Ward, Andrew C.; Connolly, Patricia; Tucker, Nicholas P.

    2014-01-01

    Electrochemical Impedance Spectroscopy (EIS) is a powerful technique that can be used to elicit information about an electrode interface. In this article, we highlight six principal processes by which the presence of microorganisms can affect impedance and show how one of these - the production of electroactive metabolites - changes the impedance signature of culture media containing Pseudomonas aeruginosa. EIS, was used in conjunction with a low cost screen printed carbon sensor to detect the presence of P. aeruginosa when grown in isolation or as part of a polymicrobial infection with Staphylococcus aureus. By comparing the electrode to a starting measurement, we were able to identify an impedance signature characteristic of P. aeruginosa. Furthermore, we are able to show that one of the changes in the impedance signature is due to pyocyanin and associated phenazine compounds. The findings of this study indicate that it might be possible to develop a low cost sensor for the detection of P. aeruginosa in important point of care diagnostic applications. In particular, we suggest that a development of the device described here could be used in a polymicrobial clinical sample such as sputum from a CF patient to detect P. aeruginosa. PMID:24614411

  6. Pseudomonas aeruginosa can be detected in a polymicrobial competition model using impedance spectroscopy with a novel biosensor.

    PubMed

    Ward, Andrew C; Connolly, Patricia; Tucker, Nicholas P

    2014-01-01

    Electrochemical Impedance Spectroscopy (EIS) is a powerful technique that can be used to elicit information about an electrode interface. In this article, we highlight six principal processes by which the presence of microorganisms can affect impedance and show how one of these--the production of electroactive metabolites--changes the impedance signature of culture media containing Pseudomonas aeruginosa. EIS, was used in conjunction with a low cost screen printed carbon sensor to detect the presence of P. aeruginosa when grown in isolation or as part of a polymicrobial infection with Staphylococcus aureus. By comparing the electrode to a starting measurement, we were able to identify an impedance signature characteristic of P. aeruginosa. Furthermore, we are able to show that one of the changes in the impedance signature is due to pyocyanin and associated phenazine compounds. The findings of this study indicate that it might be possible to develop a low cost sensor for the detection of P. aeruginosa in important point of care diagnostic applications. In particular, we suggest that a development of the device described here could be used in a polymicrobial clinical sample such as sputum from a CF patient to detect P. aeruginosa.

  7. Viable Compositional Analysis of an Eleven Species Oral Polymicrobial Biofilm

    PubMed Central

    Sherry, Leighann; Lappin, Gillian; O'Donnell, Lindsay E.; Millhouse, Emma; Millington, Owain R.; Bradshaw, David J.; Axe, Alyson S.; Williams, Craig; Nile, Christopher J.; Ramage, Gordon

    2016-01-01

    Purpose: Polymicrobial biofilms are abundant in clinical disease, particularly within the oral cavity. Creating complex biofilm models that recapitulate the polymicrobiality of oral disease are important in the development of new chemotherapeutic agents. In order to do this accurately we require the ability to undertake compositional analysis, in addition to determine individual cell viability, which is difficult using conventional microbiology. The aim of this study was to develop a defined multispecies denture biofilm model in vitro, and to assess viable compositional analysis following defined oral hygiene regimens. Methods: An in vitro multispecies denture biofilm containing various oral commensal and pathogenic bacteria and yeast was created on poly (methyl methacrylate) (PMMA). Denture hygiene regimens tested against the biofilm model included brushing only, denture cleansing only and combinational brushing and denture cleansing. Biofilm composition and viability were assessed by culture (CFU) and molecular (qPCR) methodologies. Scanning electron microscopy and confocal laser scanning microscopy were also employed to visualize changes in denture biofilms following treatment. Results: Combinational treatment of brushing and denture cleansing had the greatest impact on multispecies denture biofilms, reducing the number of live cells by more than 2 logs, and altering the overall composition in favor of streptococci. This was even more evident during the sequential testing, whereby daily sequential treatment reduced the total and live number of bacteria and yeast more than those treated intermittently. Bacteria and yeast remaining following treatment tended to aggregate in the pores of the PMMA, proving more difficult to fully eradicate the biofilm. Conclusions: Overall, we are the first to develop a method to enable viable compositional analysis of an 11 species denture biofilm following chemotherapeutic challenge. We were able to demonstrate viable cell

  8. Antimicrobial effects of carbamide peroxide against a polymicrobial biofilm model.

    PubMed

    Hasegawa, Haruhiko; Tomiyama, Kiyoshi; Kumada, Hidefumi; Kawata, Akira; Higashi, Kazuyoshi; Takahashi, Osamu; Hamada, Nobushiro; Mukai, Yoshiharu

    2015-02-01

    To investigate the in vitro antimicrobial effects of carbamide peroxide (CP) and CP-based home bleaching agents against polymicrobial (PM) biofilms. Using a high-throughput active attachment model, PM biofilms were cultured on glass coverslips by diluting the stimulated saliva of one healthy adult. All experiments were performed anaerobically in McBain medium, which was refreshed twice daily. After biofilm formation for 24 or 72 hours, the biofilms were treated with 0.5%, 2.5%, 5%, or 10% CP, 20-fold dilutions of HiLite Shade Up (HS) or Opalescence Regular (OR), 0.2% chlorhexidine digluconate (CHX), 0.2% NaF, or deionized water (n = 10 each). Biofilms were dispersed and the number of colony forming units (CFU) was measured on tryptic soy agar blood plates. Coverslips containing 72-hour biofilms treated with 0.5% and 10% CP and deionized water were stained and scanned by confocal laser scanning microscopy (CLSM). Treatment of 24- and 72-hour biofilms with HS, OR and CH yielded significantly fewer colonies than treatment with water or 0.2% NaF. No growing colonies were observed after treatment with 10% CP. CLSM showed that the percentage of dead bacteria increased as the concentration of CP increased.

  9. [PCR rDNA 16S used for the etiological diagnosis of blood culture negative endocarditis].

    PubMed

    Baty, G; Lanotte, P; Hocqueloux, L; Prazuck, T; Bret, L; Romano, M; Mereghetti, L

    2010-06-01

    We report the case of a 55 year-old man presenting with a double aortic and mitral endocarditis for which resected valve culture was repeatedly negative. Specific PCR made on valves because of highly positive blood tests for Bartonella henselae remained negative. A molecular approach was made with 16S rDNA PCR, followed by sequencing. Bartonella quintana was identified as the etiology of endocarditis. B. quintana, "fastidious" bacteria, even if hard to identify in a laboratory, is often reported as a blood culture negative endocarditis (BCNE) agent. Molecular biology methods have strongly improved the diagnosis of BCNE. We propose a review of the literature focusing on the interest of broad-spectrum PCR on valve for the etiological diagnosis of BCNE.

  10. Evaluation of the use of DMSA in culture positive UTI and culture negative acute pyelonephritis.

    PubMed

    Nammalwar, B R; Vijayakumar, M; Sankar, Janani; Ramnath, B; Prahlad, N

    2005-07-01

    This prospective study was done to assess the frequency of acute pyelonephritis (APN) in febrile children with positive urine culture as documented by Tc99m DMSA scintigraphy (DMSA) and the frequency of vesicoureteric reflux (VUR) in these children. Secondly, to determine the frequency of APN, in febrile children with supportive evidence for UTI but with negative urine culture, as documented by DMSA and frequency of VUR in them. Thirdly to stress the utility of DMSA to diagnose APN in urine culture negative febrile children and to suggest DMSA as a clinical tool in evaluation of fever of unknown origin (FUO). This study included 42 children with positive urine culture and 26 children with negative urine culture who had supportive evidence of UTI as determined by the predetermined criteria and diagnosed to have APN by DMSA. All of them had ultrasonogram (USG), DMSA and voiding cystourethrogram (VCU). They were followed up for a minimum period of 6 months. Out of the 42 children with positive urine culture 92.9% had features of APN in the DMSA of whom 82.1% had vesicoureteric relux (VUR). The DMSA was abnormal in 26 children with negative urine culture, of whom 65.4% had VUR. Ultrasound suggestive of parenchymal change was observed in 47.6% in the culture positive group and 65.4% in the culture negative group. In conclusion, it is suggested, that DMSA is a useful investigation for the diagnosis of APN in febrile UTI. DMSA is indicated in febrile children with negative urine culture but with supportive evidence of UTI and in FUO. An abnormal DMSA is a strong indication for work up for VUR.

  11. Ertapenem Articulating Spacer for the Treatment of Polymicrobial Total Knee Arthroplasty Infection

    PubMed Central

    Marinkovic, Jugoslav

    2016-01-01

    Introduction. Periprosthetic joint infections (PJIs) are the primary cause of early failure of the total knee arthroplasty (TKA). Polymicrobial TKA infections are often associated with a higher risk of treatment failure. The aim of the study was to assess the efficacy of ertapenem loaded spacers in the treatment of polymicrobial PJI. Methods. There were 18 patients enrolled; nine patients with polymicrobial PJI treated with ertapenem loaded articulating spacers were compared to the group of 9 patients treated with vancomycin or ceftazidime loaded spacers. Results. Successful reimplantation with revision implants was possible in 66.67%. Ertapenem spacers were used in 6 cases in primary two-stage procedure and in 3 cases in secondary spacer exchange. Successful infection eradication was achieved in all cases; final reimplantation with revision knee arthroplasty implants was possible in 6 cases. Conclusion. Ertapenem can be successfully used as antimicrobial addition to the cement spacers in two-stage revision treatment of polymicrobial PJIs. However, this type of spacer may also be useful in the treatment of infections caused by monomicrobial extended spectrum beta-lactamases producing gram-negative bacilli. Further clinical studies are required to evaluate the efficacy and safety of ertapenem spacers in the treatment of polymicrobial and monomicrobial PJIs. PMID:27366173

  12. Association of polymicrobial growth from urine culture with adverse pregnancy outcomes.

    PubMed

    Naresh, Amber; Simhan, Hyagriv N

    2011-08-01

    We sought to determine if pyelonephritis and preterm delivery occur more frequently among pregnant women with polymicrobial growth from screening urine culture than among women with negative urine culture. A retrospective cohort study was performed. Three hundred eighty pregnant women with greater than 100,000 colony-forming units per milliliter of polymicrobial growth from urine culture performed at less than 20 weeks of pregnancy were compared with 375 women with negative urine culture. Admissions for pyelonephritis were identified from discharge records. Gestational age at delivery was determined from a research registry. Frequency of pyelonephritis and preterm delivery did not differ between the two groups. Frequencies of pyelonephritis were 0.3% and 0% in women with polymicrobial and negative urine culture, respectively ( P=0.32). Frequencies of preterm delivery were 16.8% and 16% ( P=0.76). Among those with repeat urine cultures, 4.6% in the polymicrobial group and 2.4% of those in the negative initial urine culture group had a positive culture later in the pregnancy ( P=0.21). There is no association between polymicrobial growth from screening urine culture and pyelonephritis or preterm delivery. © Thieme Medical Publishers.

  13. Polymicrobial Multi-functional Approach for Enhancement of Crop Productivity.

    PubMed

    Reddy, Chilekampalli A; Saravanan, Ramu S

    2013-01-01

    There is an increasing global need for enhancing the food production to meet the needs of the fast-growing human population. Traditional approach to increasing agricultural productivity through high inputs of chemical nitrogen and phosphate fertilizers and pesticides is not sustainable because of high costs and concerns about global warming, environmental pollution, and safety concerns. Therefore, the use of naturally occurring soil microbes for increasing productivity of food crops is an attractive eco-friendly, cost-effective, and sustainable alternative to the use of chemical fertilizers and pesticides. There is a vast body of published literature on microbial symbiotic and nonsymbiotic nitrogen fixation, multiple beneficial mechanisms used by plant growth-promoting rhizobacteria (PGPR), the nature and significance of mycorrhiza-plant symbiosis, and the growing technology on production of efficacious microbial inoculants. These areas are briefly reviewed here. The construction of an inoculant with a consortium of microbes with multiple beneficial functions such as N(2) fixation, biocontrol, phosphate solubilization, and other plant growth-promoting properties is a positive new development in this area in that a single inoculant can be used effectively for increasing the productivity of a broad spectrum of crops including legumes, cereals, vegetables, and grasses. Such a polymicrobial inoculant containing several microorganisms for each major function involved in promoting the plant growth and productivity gives it greater stability and wider applications for a range of major crops. Intensifying research in this area leading to further advances in our understanding of biochemical/molecular mechanisms involved in plant-microbe-soil interactions coupled with rapid advances in the genomics-proteomics of beneficial microbes should lead to the design and development of inoculants with greater efficacy for increasing the productivity of a wide range of crops.

  14. Peptoid Efficacy against Polymicrobial Biofilms Determined by Using Propidium Monoazide-Modified Quantitative PCR.

    PubMed

    Luo, Yu; Bolt, Hannah L; Eggimann, Gabriela A; McAuley, Danny F; McMullan, Ronan; Curran, Tanya; Zhou, Mei; Jahoda, Professor Colin A B; Cobb, Steven L; Lundy, Fionnuala T

    2017-01-03

    Biofilms containing Candida albicans are responsible for a wide variety of clinical infections. The protective effects of the biofilm matrix, the low metabolic activity of microorganisms within a biofilm and their high mutation rate, significantly enhance the resistance of biofilms to conventional antimicrobial treatments. Peptoids are peptide-mimics that share many features of host defence antimicrobial peptides but have increased resistance to proteases and therefore have better stability in vivo. The activity of a library of peptoids was tested against monospecies and polymicrobial bacterial/fungal biofilms. Selected peptoids showed significant bactericidal and fungicidal activity against the polymicrobial biofilms. This coupled with low cytotoxicity suggests that peptoids could offer a new option for the treatment of clinically relevant polymicrobial infections.

  15. What can we learn from the microbial ecological interactions associated with polymicrobial diseases?

    PubMed

    Antiabong, J F; Boardman, W; Ball, A S

    2014-03-15

    Periodontal diseases in humans and animals are model polymicrobial diseases which are associated with a shift in the microbial community structure and function; there is therefore a need to investigate these diseases from a microbial ecological perspective. This review highlights three important areas of microbial ecological investigation of polymicrobial diseases and the lessons that could be learnt: (1) identification of disease-associated microbes and the implications for choice of anti-infective treatment; (2) the implications associated with vaccine design and development and (3) application of the dynamics of microbial interaction in the discovery of novel anti-infective agents. This review emphasises the need to invigorate microbial ecological approaches to the study of periodontal diseases and other polymicrobial diseases for greater understanding of the ecological interactions between and within the biotic and abiotic factors of the environment.

  16. Case series of Bartonella quintana blood culture-negative endocarditis in Washington, DC.

    PubMed

    Ghidey, Fisseha Y; Igbinosa, Osamuyimen; Mills, Kristin; Lai, Leon; Woods, Christian; Ruiz, Maria E; Fishbein, Dawn; Sampath, Rahul; Lowery, Robert; Wortmann, Glenn

    2016-08-01

    Prior studies (predominantly from Europe) have demonstrated blood culture-negative endocarditis due to Bartonella. Our objective was to describe three cases of Bartonella quintana endocarditis identified within one year at a large hospital in Washington, DC, USA. We constructed a descriptive case series from a retrospective review of medical records from April to December 2013 at an 800-bed urban hospital. All three patients (ages: 52, 55 and 57 years) were undomiciled/homeless men with a history of alcoholism. Although they had negative blood cultures, echocardiography demonstrated aortic/mitral valve perforation and regurgitation in one patient, aortic/mitral valve vegetation with mitral regurgitation in the second patient, and aortic valve vegetation with regurgitation in the third patient. The patients had positive Bartonella quintana serum immunoglobulin G (IgG) with negative immunoglobulin M (IgM). PCR on DNA extracted from cardiac valves was positive for Bartonella, and DNA sequencing of PCR amplicons identified Bartonella quintana. Patients received treatment with doxycycline/rifampin or doxycycline/gentamicin. Clinicians should consider Bartonella endocarditis as a differential diagnosis in patients who fit elements of the Duke Criteria, as well as having a history of homelessness and alcoholism.

  17. Comparison of characteristics of culture-negative pyogenic spondylitis and tuberculous spondylitis: a retrospective study.

    PubMed

    Kim, Chung-Jong; Kim, Eun Jung; Song, Kyoung-Ho; Choe, Pyoeng Gyun; Park, Wan Beom; Bang, Ji Hwan; Kim, Eu Suk; Park, Sang Won; Kim, Hong-Bin; Oh, Myoung-Don; Kim, Nam Joong

    2016-10-12

    Differences between the characteristics of culture positive pyogenic spondylitis (CPPS) and tuberculous spondylitis (TS) are well known. However, differences between the characteristics of culture negative pyogenic spondylitis (CNPS) and TS have not been reported; these would be more helpful in clinical practice especially when initial microbiologic examination of blood and/or biopsy tissue did not reveal the causative bacteria in patients with infectious spondylitis. We performed a retrospective review of the medical records of patients with CNPS and TS. We compared the characteristics of 71 patients with CNPS with those of 94 patients with TS. Patients with TS had more previous histories of tuberculosis (9.9 vs 22.3 %, p = 0.034), simultaneous tuberculosis other than of the spine (0 vs 47.9 %, p < 0.001), and positive results in the interferon-gamma release assay (27.6 vs 79.2 %, p < 0.001). Fever (15.5 vs. 31.8 %, p = 0.018), psoas abscesses (15.5 vs 33.0 %, p = 0.011), and paravertebral abscesses (49.3 vs. 74.5 %, p = 0.011) were also more prevalent in TS than CNPS. Different from or contrary to the previous comparisons between CPPS and TS, fever, psoas abscesses, and paravertebral abscesses are more common in patients with TS than in those with CNPS.

  18. Breeder turkey hens seropositive and culture-negative for Mycoplasma synoviae.

    PubMed

    Avakian, A P; Ley, D H; Berkhoff, J E; Ficken, M D

    1992-01-01

    Four flocks of clinically normal turkey breeder hens were shown to have suspect and positive Mycoplasma synoviae (MS) hemagglutination-inhibition (HI), enzyme-linked immunosorbent assay, and, in some cases, serum plate agglutination serology in the absence of MS isolation. In all cases, HI serology for Mycoplasma gallisepticum (MG) and M. meleagridis was negative. Acholeplasma laidlawii was isolated from some hens in each of these MS-seropositive culture-negative flocks. Immunoblotting was used to help determine if this positive MS serology was a result of cross-reactive antibodies to A. laidlawii or to some other Mycoplasma species. When sera from two of the flocks were reacted with MS antigen in immunoblotting, a strong and characteristic MS immunoblot profile was seen. Immunoblotting gave no evidence of a strong antibody response to A. laidlawii, M. iowae, or MG. This suggests the presence (or earlier presence) of MS in these flocks that is difficult to isolate by routine methods. Furthermore, this work shows that immunoblotting can be an important tool in the diagnosis of poultry diseases.

  19. Case series of Bartonella quintana blood culture-negative endocarditis in Washington, DC

    PubMed Central

    Ghidey, Fisseha Y.; Mills, Kristin; Lai, Leon; Woods, Christian; Ruiz, Maria E.; Fishbein, Dawn; Sampath, Rahul; Lowery, Robert; Wortmann, Glenn

    2016-01-01

    Introduction: Prior studies (predominantly from Europe) have demonstrated blood culture-negative endocarditis due to Bartonella. Our objective was to describe three cases of Bartonella quintana endocarditis identified within one year at a large hospital in Washington, DC, USA. Case presentation: We constructed a descriptive case series from a retrospective review of medical records from April to December 2013 at an 800-bed urban hospital. All three patients (ages: 52, 55 and 57 years) were undomiciled/homeless men with a history of alcoholism. Although they had negative blood cultures, echocardiography demonstrated aortic/mitral valve perforation and regurgitation in one patient, aortic/mitral valve vegetation with mitral regurgitation in the second patient, and aortic valve vegetation with regurgitation in the third patient. The patients had positive Bartonella quintana serum immunoglobulin G (IgG) with negative immunoglobulin M (IgM). PCR on DNA extracted from cardiac valves was positive for Bartonella, and DNA sequencing of PCR amplicons identified Bartonella quintana. Patients received treatment with doxycycline/rifampin or doxycycline/gentamicin. Conclusion: Clinicians should consider Bartonella endocarditis as a differential diagnosis in patients who fit elements of the Duke Criteria, as well as having a history of homelessness and alcoholism. PMID:28348772

  20. Metabolic crosstalk regulates Porphyromonas gingivalis colonization and virulence during oral polymicrobial infection.

    PubMed

    Kuboniwa, Masae; Houser, John R; Hendrickson, Erik L; Wang, Qian; Alghamdi, Samar A; Sakanaka, Akito; Miller, Daniel P; Hutcherson, Justin A; Wang, Tiansong; Beck, David A C; Whiteley, Marvin; Amano, Atsuo; Wang, Huizhi; Marcotte, Edward M; Hackett, Murray; Lamont, Richard J

    2017-09-18

    Many human infections are polymicrobial in origin, and interactions among community inhabitants shape colonization patterns and pathogenic potential (1) . Periodontitis, which is the sixth most prevalent infectious disease worldwide (2) , ensues from the action of dysbiotic polymicrobial communities (3) . The keystone pathogen Porphyromonas gingivalis and the accessory pathogen Streptococcus gordonii interact to form communities in vitro and exhibit increased fitness in vivo (3,4) . The mechanistic basis of this polymicrobial synergy, however, has not been fully elucidated. Here we show that streptococcal 4-aminobenzoate/para-amino benzoic acid (pABA) is required for maximal accumulation of P. gingivalis in dual-species communities. Metabolomic and proteomic data showed that exogenous pABA is used for folate biosynthesis, and leads to decreased stress and elevated expression of fimbrial adhesins. Moreover, pABA increased the colonization and survival of P. gingivalis in a murine oral infection model. However, pABA also caused a reduction in virulence in vivo and suppressed extracellular polysaccharide production by P. gingivalis. Collectively, these data reveal a multidimensional aspect to P. gingivalis-S. gordonii interactions and establish pABA as a critical cue produced by a partner species that enhances the fitness of P. gingivalis while diminishing its virulence.Streptococcal para-amino benzoic acid enhances Porphyromonas gingivalis colonization while reducing virulence during polymicrobial oral infection.

  1. Effects of natural honey on polymicrobial culture of various human pathogens

    PubMed Central

    Al-Waili, Faiza S.; Akmal, Mohammed; Ali, Amjed; Salom, Khelod Y.; Al Ghamdi, Ahmad A.

    2012-01-01

    Introduction Honey has a wide range of antimicrobial activity. All previous studies have considered honey's effect on a single microbe. The present study investigated activity of honey towards a high dose of single or polymicrobial culture. Material and methods 10 µl specimens of Staphylococcus aureus (S. aureus), Streptococcus pyogenes (S. pyogenes), Escherichia coli (E. coli) and Candida albicans (C. albicans) were cultured in 10 ml of 10-100% (wt/v) honey diluted in broth. Six types of polymicrobial microbial cultures were prepared by culturing the isolates with each other onto broth (control) and broth containing various concentrations of honey (10-100% wt/v). Microbial growth was assessed on solid plate media after 24 h incubation. Results Honey (30-70%) prevents growth of 10 µl specimens of all the isolates. Greater reduction in growth of E. coli was observed when cultured with S. aureus. Culturing of S. aureus with S. pyogenes, C. albicans, or E. coli increased its sensitivity to honey. S. aureus and S. pyogenes increased sensitivity of C. albicans to honey while E. coli and C. albicans decreased sensitivity of S. pyogenes. Conclusions It might be concluded that honey prevents and inhibits growth of single and polymicrobial pathogenic cultures. Polymicrobial culture affects growth of the isolates and increases their sensitivity to honey. PMID:24904656

  2. Polymicrobial Chronic Infection Including Acinetobacter Baumannii in a Plated Segmental Defect in the Rat Femur

    DTIC Science & Technology

    2008-01-01

    Including Acinetobacter baumannii in a Plated Segmental Defect in the Rat Femur PRINCIPAL INVESTIGATOR: Dean T. Tsukayama, MD...FEB 2007 - 31 DEC 2007 4. TITLE AND SUBTITLE Polymicrobial Chronic Infection Including Acinetobacter baumannii 5a. CONTRACT NUMBER in a Plated...bone isolate of Acinetobacter baumannii exhibited very little osteolytic involvement when used alone in the model. Qualitative cultures indicated very

  3. Exploring Preterm Birth as a Polymicrobial Disease: An Overview of the Uterine Microbiome

    PubMed Central

    Payne, Matthew S.; Bayatibojakhi, Sara

    2014-01-01

    Infection is a leading cause of preterm birth (PTB). A focus of many studies over the past decade has been to characterize microorganisms present in the uterine cavity and document any association with negative pregnancy outcome. A range of techniques have been used to achieve this, including microbiological culture and targeted polymerase chain reaction assays, and more recently, microbiome-level analyses involving either conserved, phylogenetically informative genes such as the bacterial 16S rRNA gene or whole shotgun metagenomic sequencing. These studies have contributed vast amounts of data toward characterization of the uterine microbiome, specifically that present in the amniotic fluid, fetal membranes, and placenta. However, an overwhelming emphasis has been placed on the bacterial microbiome, with far less data produced on the viral and fungal/yeast microbiomes. With numerous studies now referring to PTB as a polymicrobial condition, there is the need to investigate the role of viruses and fungi/yeasts in more detail and in particular, look for associations between colonization with these microorganisms and bacteria in the same samples. Although the major pathway by which microorganisms are believed to colonize the uterine cavity is vertical ascension from the vagina, numerous studies are now emerging suggesting hematogenous transfer of oral microbiota to the uterine cavity. Evidence of this has been produced in mouse models and although DNA-based evidence in humans appears convincing in some aspects, use of methodologies that only detect viable cells as opposed to lysed cells and extracellular DNA are needed to clarify this. Such techniques as RNA analyses and viability polymerase chain reaction are likely to play key roles in the clinical translation of future microbiome-based data, particularly in confined environments such as the uterus, as detection of viable cells plays a key role in diagnosis and treatment of infection. PMID:25505898

  4. Efficacy of Ethanol against Candida albicans and Staphylococcus aureus Polymicrobial Biofilms

    PubMed Central

    Peters, Brian M.; Ward, Raven M.; Rane, Hallie S.; Lee, Samuel A.

    2013-01-01

    Candida albicans, an opportunistic fungus, and Staphylococcus aureus, a bacterial pathogen, are two clinically relevant biofilm-forming microbes responsible for a majority of catheter-related infections, with such infections often resulting in catheter loss and removal. Not only do these pathogens cause a substantial number of nosocomial infections independently, but also they are frequently found coexisting as polymicrobial biofilms on host and environmental surfaces. Antimicrobial lock therapy is a current strategy to sterilize infected catheters. However, the robustness of this technique against polymicrobial biofilms has remained largely untested. Due to its antimicrobial activity, safety, stability, and affordability, we tested the hypothesis that ethanol (EtOH) could serve as a potentially efficacious catheter lock solution against C. albicans and S. aureus biofilms. Therefore, we optimized the dose and time necessary to achieve killing of both monomicrobial and polymicrobial biofilms formed on polystyrene and silicone surfaces in a static microplate lock therapy model. Treatment with 30% EtOH for a minimum of 4 h was inhibitory for monomicrobial and polymicrobial biofilms, as evidenced by XTT {sodium 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide inner salt} metabolic activity assays and confocal microscopy. Experiments to determine the regrowth of microorganisms on silicone after EtOH treatment were also performed. Importantly, incubation with 30% EtOH for 4 h was sufficient to kill and inhibit the growth of C. albicans, while 50% EtOH was needed to completely inhibit the regrowth of S. aureus. In summary, we have systematically defined the dose and duration of EtOH treatment that are effective against and prevent regrowth of C. albicans and S. aureus monomicrobial and polymicrobial biofilms in an in vitro lock therapy model. PMID:23070170

  5. A comparison of monomicrobial versus polymicrobial Enterococcus faecalis bacteriuria in a French University Hospital.

    PubMed

    Fourcade, C; Canini, L; Lavigne, J-P; Sotto, A

    2015-08-01

    Enterococci are of considerable relevance in the hospital setting. Their most common location is the urinary tract, where they may be responsible for both colonization and infections. They are often associated with the presence of other microorganisms. The aim was to compare monomicrobial and polymicrobial Enterococcus faecalis bacteriuria. A retrospective study was performed on the demographic, clinical, and laboratory data of 299 patients who had presented with E. faecalis bacteriuria in 2012 at a University Hospital. The bacteriuria was polymicrobial in 46.1 % of cases and in 36.4 % of cases was responsible for a urinary tract infection. Infections appeared to be more prevalent in the polymicrobial than the monomicrobial group (42 % vs 32 %, p = 0.06). Half of the patients who presented with urinary tract colonization received antibiotic treatment (54/ out of 10). A multivariate analysis adjusted for age (adjusted odds ratio [AOR] = 1.02 per year, p = 0.006), gender (AOR = 2.2, p = 0.007), and clinical classification (colonization or infection, AOR = 1.6, p = 0.091), showed that diabetes mellitus (AOR = 2.0, p = 0.04), hospital length of stay exceeding 28 days (AOR = 2.0, p = 0.03), and presence of a urinary catheter (AOR = 2.4, p = 0.001) were all factors associated with polymicrobial E. faecalis bacteriuria. A reduction in the length of hospital stay and the use of urinary catheters would appear to be required to decrease the incidence of urinary tract colonization and infections by polymicrobial E. faecalis. Improper use of antibiotics to treat urinary tract colonization remains a major concern.

  6. Results after late polymicrobial, gram-negative, and methicillin-resistant infections in knee arthroplasty.

    PubMed

    Cordero-Ampuero, José; Esteban, Jaime; García-Rey, Eduardo

    2010-05-01

    Previous studies of knee arthroplasty infections caused by high-virulence organisms suggest poor outcomes. Polymicrobial and Gram-negative infections are less studied. This study compared the results of treatment of knee arthroplasty infections by single versus polymicrobial isolates, Gram-positive versus Gram-negative, and methicillin-resistant versus -sensitive Staphylococci. We prospectively followed 47 patients with late knee arthroplasty infections. The mean age was 72 years (range, 20-87 years). The treatment protocol included two-stage exchange and a combination of two oral antibiotics given for 6 months. Minimum followup was 1 year (average, 4.8 +/- 3 years; range, 1-12 years). Control of the infection was judged by absence of clinical, serologic, and radiologic signs of infection. The functional outcome was evaluated by Knee Society score at the last followup. Infection was controlled in all 15 patients with polymicrobial and in 28 of 32 (88%) with monomicrobial infections, in eight of nine patients with Gram-negative and in 35 of 38 (92%) with Gram-positive isolates. Control was also achieved in 22 of 25 patients (88%) infected by methicillin-resistant Staphylococci and in 14 of 14 by methicillin-sensitive Staphylococci. The Knee Society scores averaged 81-63 in patients with polymicrobial infections and were higher than in monomicrobial infections (75-52). The mean KSS was 85-59 in Gram-negative infections compared to 75-55 in Gram-positive infections. The mean KSS was similar in methicillin-resistant (78-54) and methicillin-sensitive Staphylococci (73-56) infections. Polymicrobial and Gram-negative infections can be controlled in late knee arthroplasty infections. On the other hand, infections by methicillin-resistant Staphylococci are less likely to be controlled by the regimens we used. Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

  7. Efficacy of ethanol against Candida albicans and Staphylococcus aureus polymicrobial biofilms.

    PubMed

    Peters, Brian M; Ward, Raven M; Rane, Hallie S; Lee, Samuel A; Noverr, Mairi C

    2013-01-01

    Candida albicans, an opportunistic fungus, and Staphylococcus aureus, a bacterial pathogen, are two clinically relevant biofilm-forming microbes responsible for a majority of catheter-related infections, with such infections often resulting in catheter loss and removal. Not only do these pathogens cause a substantial number of nosocomial infections independently, but also they are frequently found coexisting as polymicrobial biofilms on host and environmental surfaces. Antimicrobial lock therapy is a current strategy to sterilize infected catheters. However, the robustness of this technique against polymicrobial biofilms has remained largely untested. Due to its antimicrobial activity, safety, stability, and affordability, we tested the hypothesis that ethanol (EtOH) could serve as a potentially efficacious catheter lock solution against C. albicans and S. aureus biofilms. Therefore, we optimized the dose and time necessary to achieve killing of both monomicrobial and polymicrobial biofilms formed on polystyrene and silicone surfaces in a static microplate lock therapy model. Treatment with 30% EtOH for a minimum of 4 h was inhibitory for monomicrobial and polymicrobial biofilms, as evidenced by XTT {sodium 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide inner salt} metabolic activity assays and confocal microscopy. Experiments to determine the regrowth of microorganisms on silicone after EtOH treatment were also performed. Importantly, incubation with 30% EtOH for 4 h was sufficient to kill and inhibit the growth of C. albicans, while 50% EtOH was needed to completely inhibit the regrowth of S. aureus. In summary, we have systematically defined the dose and duration of EtOH treatment that are effective against and prevent regrowth of C. albicans and S. aureus monomicrobial and polymicrobial biofilms in an in vitro lock therapy model.

  8. Searching for new strategies against polymicrobial biofilm infections: guanylated polymethacrylates kill mixed fungal/bacterial biofilms.

    PubMed

    Qu, Yue; Locock, Katherine; Verma-Gaur, Jiyoti; Hay, Iain D; Meagher, Laurence; Traven, Ana

    2016-02-01

    Biofilm-related human infections have high mortality rates due to drug resistance. Cohabitation of diverse microbes in polymicrobial biofilms is common and these infections present additional challenges for treatment compared with monomicrobial biofilms. Here, we address this therapeutic gap by assessing the potential of a new class of antimicrobial agents, guanylated polymethacrylates, in the treatment of polymicrobial biofilms built by two prominent human pathogens, the fungus Candida albicans and the bacterium Staphylococcus aureus. We used imaging and quantitative methods to test the antibiofilm efficacy of guanylated polymethacrylates, a new class of drugs that structurally mimic antimicrobial peptides. We further compared guanylated polymethacrylates with first-line antistaphylococcal and anti-Candida agents used as combinatorial therapy against polymicrobial biofilms. Guanylated polymethacrylates were highly effective as a sole agent, killing both C. albicans and S. aureus when applied to established polymicrobial biofilms. Furthermore, they outperformed multiple combinations of current antimicrobial drugs, with one of the tested compounds killing 99.98% of S. aureus and 82.2% of C. albicans at a concentration of 128 mg/L. The extracellular biofilm matrix provided protection, increasing the MIC of the polymethacrylates by 2-4-fold when added to planktonic assays. Using the C. albicans bgl2ΔΔ mutant, we implicate matrix polysaccharide β-1,3 glucan in the mechanism of protection. Data for two structurally distinct polymers suggest that this mechanism could be minimized through chemical optimization of the polymer structure. Finally, we demonstrate that a potential application for these polymers is in antimicrobial lock therapy. Guanylated polymethacrylates are a promising lead for the development of an effective monotherapy against C. albicans/S. aureus polymicrobial biofilms. © The Author 2015. Published by Oxford University Press on behalf of the British

  9. The development and application of a molecular community profiling strategy to identify polymicrobial bacterial DNA in the whole blood of septic patients.

    PubMed

    Faria, M M P; Conly, J M; Surette, M G

    2015-10-16

    The application of molecular based diagnostics in sepsis has had limited success to date. Molecular community profiling methods have indicated that polymicrobial infections are more common than suggested by standard clinical culture. A molecular profiling approach was developed to investigate the propensity for polymicrobial infections in patients predicted to have bacterial sepsis. Disruption of blood cells with saponin and hypotonic shock enabled the recovery of microbial cells with no significant changes in microbial growth when compared to CFU/ml values immediately prior to the addition of saponin. DNA extraction included a cell-wall digestion step with both lysozyme and mutanolysin, which increased the recovery of terminal restriction fragments by 2.4 fold from diverse organisms. Efficiencies of recovery and limits of detection using Illumina sequencing of the 16S rRNA V3 region were determined for both viable cells and DNA using mock bacterial communities inoculated into whole blood. Bacteria from pre-defined communities could be recovered following lysis and removal of host cells with >97% recovery of total DNA present. Applying the molecular profiling methodology to three septic patients in the intensive care unit revealed microbial DNA from blood had consistent alignment with cultured organisms from the primary infection site providing evidence for a bloodstream infection in the absence of a clinical lab positive blood culture result in two of the three cases. In addition, the molecular profiling indicated greater diversity was present in the primary infection sample when compared to clinical diagnostic culture. A method for analyzing bacterial DNA from whole blood was developed in order to characterize the bacterial DNA profile of sepsis infections. Preliminary results indicated that sepsis infections were polymicrobial in nature with the bacterial DNA recovered suggesting a more complex etiology when compared to blood culture data.

  10. [Infective endocarditis in intensive cardiac care unit - clinical and biochemical differences of blood-culture negative infective endocarditis].

    PubMed

    Kaziród-Wolski, Karol; Sielski, Janusz; Ciuraszkiewicz, Katarzyna

    2017-01-23

    Diagnosis and treatment of infective endocarditis (IE) is still a challenge for physicians. Group of patients with the worst prognosis is treated in Intensive Cardiac Care Unit (ICCU). Etiologic agent can not be identified in a substantial number of patients. The aim of study is to find differences between patients with blood culture negative infective endocarditis (BCNIE) and blood culture positive infective endocarditis (BCPIE) treated in ICCU by comparing their clinical course and laboratory parameters. Retrospective analysis of 30 patients with IE hospitalized in ICCU Swietokrzyskie Cardiac Centre between 2010 and 2016. This group consist of 26 men (86,67%) and 4 women (13,3%). Mean age was 58 years ±13. Most of the cases were new disease, recurrence of the disease was observed in 2 cases (6,7%). 8 patients (26,7%) required artificial ventilation, 11 (36,7%) received inotropes and 6 (20%) vasopresors. In 14 (46,7%) cases blood cultures was negative (BCNIE), the rest of patients (16, 53,3%) was blood cultures - positive infective endocarditis (BCIE). Both of the groups were clinically similar. There were no statistically significant differences in incidence of cardiac implants, localization of bacterial vegetations, administered catecholamines, antibiotic therapy, artificial ventilation, surgical treatment, complication and in-hospital mortality. Incidence of cardiac complications in all of BCNIE cases and in 81,3% cases of BCPIE draws attention, but it is not statistically significant difference (p=0,08). There was statistically significant difference in mean BNP blood concentration (3005,17 ng/ml ±2045,2 vs 1013,42 ng/ml ±1087,6; p=0,01), but there were no statistically significant differences in rest of laboratory parameters. BCNIE group has got higher mean BNP blood concentration than BCPIE group. There were no statistically significant differences between these groups in others laboratory parameters, clinical course and administered antibiotic therapy

  11. The Role of the Vagus Nerve: Modulation of the Inflammatory Reaction in Murine Polymicrobial Sepsis

    PubMed Central

    Kessler, Wolfram; Diedrich, Stephan; Menges, Pia; Ebker, Tobias; Nielson, Michael; Partecke, Lars Ivo; Traeger, Tobias; Cziupka, Katharina; van der Linde, Julia; Puls, Ralf; Busemann, Alexandra; Heidecke, Claus-Dieter; Maier, Stefan

    2012-01-01

    The particular importance of the vagus nerve for the pathophysiology of peritonitis becomes more and more apparent. In this work we provide evidence for the vagal modulation of inflammation in the murine model of colon ascendens stent peritonitis (CASP). Vagotomy significantly increases mortality in polymicrobial sepsis. This effect is not accounted for by the dilatation of gastric volume following vagotomy. As the stimulation of cholinergic receptors by nicotine has no therapeutic effect, the lack of nicotine is also not the reason for the reduced survival rate. In fact, increased septic mortality is a consequence of the absent modulating influence of the vagus nerve on the immune system: we detected significantly elevated serum corticosterone levels in vagotomised mice 24 h following CASP and a decreased ex vivo TNF-alpha secretion of Kupffer cells upon stimulation with LPS. In conclusion, the vagus nerve has a modulating influence in polymicrobial sepsis by attenuating the immune dysregulation. PMID:22547905

  12. A novel natural compound from garlic (Allium sativum L.) with therapeutic effects against experimental polymicrobial sepsis.

    PubMed

    Lee, Sung Kyun; Park, Yoo Jung; Ko, Min Jung; Wang, Ziyu; Lee, Ha Young; Choi, Young Whan; Bae, Yoe-Sik

    2015-08-28

    Sepsis is a serious, life-threatening, infectious disease. In this study, we demonstrate that sucrose methyl 3-formyl-4-methylpentanoate (SMFM), a novel natural compound isolated from garlic (Allium sativum L.), markedly enhances survival rates by inhibiting lung inflammation in a cecal ligation and puncture (CLP) experimental polymicrobial sepsis model. SMFM strongly reduced bacterial colony units from peritoneal fluid in CLP mice by stimulating the generation of reactive oxygen species. Lymphocyte apoptosis in spleens from CLP mice was also markedly decreased by SMFM administration. SMFM also significantly inhibited the production of proinflammatory cytokines, such as TNF-α, interleukin-1β (IL-1β) and IL-6, in CLP mice. Lipopolysaccharide-stimulated production of TNF-α and IL-6 were also strongly inhibited by SMFM in mouse bone marrow-derived macrophages. Taken together, our results indicate that SMFM has therapeutic effects against polymicrobial sepsis that are mediated by enhanced microbial killing and blockage of cytokine storm.

  13. Detection and Quantification of Mycobacterium tuberculosis in the Sputum of Culture-Negative HIV-infected Pulmonary Tuberculosis Suspects: A Proof-of-Concept Study

    PubMed Central

    Madico, Guillermo; Mpeirwe, Moses; White, Laura; Vinhas, Solange; Orr, Beverley; Orikiriza, Patrick; Miller, Nancy S.; Gaeddert, Mary; Mwanga-Amumpaire, Juliet; Palaci, Moises; Kreiswirth, Barry; Straight, Joe; Dietze, Reynaldo; Boum, Yap; Jones-López, Edward C.

    2016-01-01

    Rationale Rapid diagnosis of pulmonary tuberculosis (TB) is critical for timely initiation of treatment and interruption of transmission. Yet, despite recent advances, many patients remain undiagnosed. Culture, usually considered the most sensitive diagnostic method, is sub-optimal for paucibacillary disease. Methods We evaluated the Totally Optimized PCR (TOP) TB assay, a new molecular test that we hypothesize is more sensitive than culture. After pre-clinical studies, we estimated TOP’s per-patient sensitivity and specificity in a convenience sample of 261 HIV-infected pulmonary TB suspects enrolled into a TB diagnostic study in Mbarara, Uganda against MGIT culture, Xpert MTB/RIF and a composite reference standard. We validated results with a confirmatory PCR used for sequencing M. tuberculosis. Measurements and Results Using culture as reference, TOP had 100% sensitivity but 35% specificity. Against a composite reference standard, the sensitivity of culture (27%) and Xpert MTB/RIF (27%) was lower than TOP (99%), with similar specificity (100%, 98% and 87%, respectively). In unadjusted analyses, culture-negative/TOP-positive patients were more likely to be older (P<0·001), female (P<0·001), have salivary sputum (P = 0·05), sputum smear-negative (P<0.001) and less advanced disease on chest radiograph (P = 0.05). M. tuberculosis genotypes identified in sputum by DNA sequencing exhibit differential growth in culture. Conclusions These findings suggest that the TOP TB assay is accurately detecting M. tuberculosis DNA in the sputum of culture-negative tuberculosis suspects. Our results require prospective validation with clinical outcomes. If the operating characteristics of the TOP assay are confirmed in future studies, it will be justified as a “TB rule out” test. PMID:27391604

  14. The synthetic antimicrobial peptide 19-2.5 attenuates septic cardiomyopathy and prevents down-regulation of SERCA2 in polymicrobial sepsis

    PubMed Central

    Martin, Lukas; Horst, Klemens; Chiazza, Fausto; Oggero, Silvia; Collino, Massimo; Brandenburg, Klaus; Hildebrand, Frank; Marx, Gernot; Thiemermann, Christoph; Schuerholz, Tobias

    2016-01-01

    An impairment of cardiac function is a key feature of the cardiovascular failure associated with sepsis. Although there is some evidence that suppression of sarcoplasmic reticulum Ca2+-ATP-ase (SERCA2) contributes to septic cardiomyopathy, it is not known whether prevention of the down-regulation of SERCA2 improves outcome in sepsis. Thus, we investigated whether the administration of the synthetic antimicrobial peptide Pep2.5 may attenuate the cardiac dysfunction in murine polymicrobial sepsis through regulating SERCA2 expression. We show here for the first time that the infusion of Pep2.5 reduces the impaired systolic and diastolic contractility and improves the survival time in polymicrobial sepsis. Preservation of cardiac function in sepsis by Pep2.5 is associated with prevention of the activation of NF-κB and activation of the Akt/eNOS survival pathways. Most notably, Pep2.5 prevented the down-regulation of SERCA2 expression in a) murine heart samples obtained from mice with sepsis and b) in cardiomyocytes exposed to serum from septic shock patients. Thus, we speculate that Pep2.5 may be able to prevent down-regulation of cardiac SERCA2 expression in patients with sepsis, which, in turn, may improve cardiac function and outcome in these patients. PMID:27853260

  15. Sheltering effect and indirect pathogenesis of carbapenem-resistant Acinetobacter baumannii in polymicrobial infection.

    PubMed

    Liao, Yu-Ting; Kuo, Shu-Chen; Lee, Yi-Tzu; Chen, Chien-Pei; Lin, Shu-Wen; Shen, Li-Jiuan; Fung, Chang-Phone; Cho, Wen-Long; Chen, Te-Li

    2014-07-01

    The role of carbapenem-resistant Acinetobacter baumannii (CRAb) in polymicrobial infection remains elusive. Having observed the ability of CRAb to shelter other susceptible bacteria from carbapenem killing, we sought to determine the factors contributing to this sheltering effect by transforming different recombinant plasmids into recipient A. baumannii cells. The sheltering effects of CRAb were reproduced in recipient A. baumannii cells that highly expressed carbapenem-hydrolyzing class D β-lactamases (CHDLs) through their associated strong promoter. With the use of Western blot analysis and a bioassay, the highly expressed CHDLs were found to be extracellularly released and led to hydrolysis of carbapenem. The level of extracellular CHDLs increased after challenge with a higher concentration of CHDL substrates, such as carbapenem and ticarcillin. This increased CHDL may, in part, be attributed to cell lysis, as indicated by the presence of extracellular gyrase. In the planktonic condition, the sheltering effect for the cocultured susceptible bacteria might represent an indirect and passive effect of the CRAb self-defense mechanism, because coculture with the susceptible pathogen did not augment the amount of the extracellular CHDLs. Polymicrobial infection caused by CRAb and a susceptible counterpart exerted higher pathogenicity than monomicrobial infection caused by either pathogen alone in mice receiving carbapenem therapy. This study demonstrated that CHDL-producing CRAb appears to provide a sheltering effect for carbapenem-susceptible pathogens via the extracellular release of CHDLs and, by this mechanism, can enhance the pathogenesis of polymicrobial infection in the presence of carbapenem therapy.

  16. Interactions of Methicillin Resistant Staphylococcus aureus USA300 and Pseudomonas aeruginosa in Polymicrobial Wound Infection

    PubMed Central

    Pastar, Irena; Nusbaum, Aron G.; Gil, Joel; Patel, Shailee B.; Chen, Juan; Valdes, Jose; Stojadinovic, Olivera; Plano, Lisa R.; Tomic-Canic, Marjana; Davis, Stephen C.

    2013-01-01

    Understanding the pathology resulting from Staphylococcus aureus and Pseudomonas aeruginosa polymicrobial wound infections is of great importance due to their ubiquitous nature, increasing prevalence, growing resistance to antimicrobial agents, and ability to delay healing. Methicillin-resistant S. aureus USA300 is the leading cause of community-associated bacterial infections resulting in increased morbidity and mortality. We utilized a well-established porcine partial thickness wound healing model to study the synergistic effects of USA300 and P. aeruginosa on wound healing. Wound re-epithelialization was significantly delayed by mixed-species biofilms through suppression of keratinocyte growth factor 1. Pseudomonas showed an inhibitory effect on USA300 growth in vitro while both species co-existed in cutaneous wounds in vivo. Polymicrobial wound infection in the presence of P. aeruginosa resulted in induced expression of USA300 virulence factors Panton-Valentine leukocidin and α-hemolysin. These results provide evidence for the interaction of bacterial species within mixed-species biofilms in vivo and for the first time, the contribution of virulence factors to the severity of polymicrobial wound infections. PMID:23451098

  17. Comparative genome analysis and identification of competitive and cooperative interactions in a polymicrobial disease.

    PubMed

    Endo, Akiko; Watanabe, Takayasu; Ogata, Nachiko; Nozawa, Takashi; Aikawa, Chihiro; Arakawa, Shinichi; Maruyama, Fumito; Izumi, Yuichi; Nakagawa, Ichiro

    2015-03-01

    Polymicrobial diseases are caused by combinations of multiple bacteria, which can lead to not only mild but also life-threatening illnesses. Periodontitis represents a polymicrobial disease; Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia, called 'the red complex', have been recognized as the causative agents of periodontitis. Although molecular interactions among the three species could be responsible for progression of periodontitis, the relevant genetic mechanisms are unknown. In this study, we uncovered novel interactions in comparative genome analysis among the red complex species. Clustered regularly interspaced short palindromic repeats (CRISPRs) of T. forsythia might attack the restriction modification system of P. gingivalis, and possibly work as a defense system against DNA invasion from P. gingivalis. On the other hand, gene deficiencies were mutually compensated in metabolic pathways when the genes of all the three species were taken into account, suggesting that there are cooperative relationships among the three species. This notion was supported by the observation that each of the three species had its own virulence factors, which might facilitate persistence and manifestations of virulence of the three species. Here, we propose new mechanisms of bacterial symbiosis in periodontitis; these mechanisms consist of competitive and cooperative interactions. Our results might shed light on the pathogenesis of periodontitis and of other polymicrobial diseases.

  18. Insights into Dynamic Polymicrobial Synergy Revealed by Time-Coursed RNA-Seq

    PubMed Central

    Hendrickson, Erik L.; Beck, David A. C.; Miller, Daniel P.; Wang, Qian; Whiteley, Marvin; Lamont, Richard J.; Hackett, Murray

    2017-01-01

    Many bacterial infections involve polymicrobial communities in which constituent organisms are synergistically pathogenic. Periodontitis, a commonly occurring chronic inflammatory disorder, is induced by multispecies bacterial communities. The periodontal keystone pathogen Porphyromonas gingivalis and the accessory pathogen Streptococcus gordonii exhibit polymicrobial synergy in animal models of disease. Mechanisms of co-adhesion and community formation by P. gingivalis and S. gordonii are well-established; however, little is known regarding the basis for increased pathogenicity. In this study we used time-coursed RNA-Seq to comprehensively and quantitatively examine the dynamic transcriptional landscape of P. gingivalis in a model consortium with S. gordonii. Genes encoding a number of potential virulence determinants had higher relative mRNA levels in the context of dual species model communities than P. gingivalis alone, including adhesins, the Type IX secretion apparatus, and tetratricopeptide repeat (TPR) motif proteins. In contrast, genes encoding conjugation systems and many of the stress responses showed lower levels of expression in P. gingivalis. A notable exception to reduced abundance of stress response transcripts was the genes encoding components of the oxidative stress-related OxyR regulon, indicating an adaptation of P. gingivalis to detoxify peroxide produced by the streptococcus. Collectively, the results are consistent with evolutionary adaptation of P. gingivalis to a polymicrobial oral environment, one outcome of which is increased pathogenic potential. PMID:28293219

  19. Interaction networks, ecological stability, and collective antibiotic tolerance in polymicrobial infections.

    PubMed

    de Vos, Marjon G J; Zagorski, Marcin; McNally, Alan; Bollenbach, Tobias

    2017-09-18

    Polymicrobial infections constitute small ecosystems that accommodate several bacterial species. Commonly, these bacteria are investigated in isolation. However, it is unknown to what extent the isolates interact and whether their interactions alter bacterial growth and ecosystem resilience in the presence and absence of antibiotics. We quantified the complete ecological interaction network for 72 bacterial isolates collected from 23 individuals diagnosed with polymicrobial urinary tract infections and found that most interactions cluster based on evolutionary relatedness. Statistical network analysis revealed that competitive and cooperative reciprocal interactions are enriched in the global network, while cooperative interactions are depleted in the individual host community networks. A population dynamics model parameterized by our measurements suggests that interactions restrict community stability, explaining the observed species diversity of these communities. We further show that the clinical isolates frequently protect each other from clinically relevant antibiotics. Together, these results highlight that ecological interactions are crucial for the growth and survival of bacteria in polymicrobial infection communities and affect their assembly and resilience.

  20. Impact of polymicrobial biofilms in catheter-associated urinary tract infections.

    PubMed

    Azevedo, Andreia S; Almeida, Carina; Melo, Luís F; Azevedo, Nuno F

    2016-12-30

    Recent reports have demonstrated that most biofilms involved in catheter-associated urinary tract infections are polymicrobial communities, with pathogenic microorganisms (e.g. Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae) and uncommon microorganisms (e.g. Delftia tsuruhatensis, Achromobacter xylosoxidans) frequently co-inhabiting the same urinary catheter. However, little is known about the interactions that occur between different microorganisms and how they impact biofilm formation and infection outcome. This lack of knowledge affects CAUTIs management as uncommon bacteria action can, for instance, influence the rate at which pathogens adhere and grow, as well as affect the overall biofilm resistance to antibiotics. Another relevant aspect is the understanding of factors that drive a single pathogenic bacterium to become prevalent in a polymicrobial community and subsequently cause infection. In this review, a general overview about the IMDs-associated biofilm infections is provided, with an emphasis on the pathophysiology and the microbiome composition of CAUTIs. Based on the available literature, it is clear that more research about the microbiome interaction, mechanisms of biofilm formation and of antimicrobial tolerance of the polymicrobial consortium are required to better understand and treat these infections.

  1. Development and antimicrobial susceptibility studies of in vitro monomicrobial and polymicrobial biofilm models with Aspergillus fumigatus and Pseudomonas aeruginosa

    PubMed Central

    2014-01-01

    Background Mixed microbial infections of the respiratory tracts with P. aeruginosa and A. fumigatus capable of producing biofilms are commonly found in cystic fibrosis patients. The primary objective of this study was to develop an in vitro model for P. aeruginosa and A. fumigatus polymicrobial biofilm to study the efficacy of various antimicrobial drugs alone and in combinations against biofilm-embedded cells. Simultaneous static cocultures of P. aeruginosa and sporelings were used for the development of in vitro P. aeruginosa-A. fumigatus polymicrobial biofilm in SD broth in 24-well cell culture plates at 35°C, and the biofilm formation was monitored microscopically and spectrophotometrically. Using P. aeruginosa-A. fumigatus sporelings cocultures we examined the effects of various antimicrobial drugs alone and in combination against polymicrobial biofilm by CFU and tetrazolium reduction assays. Results In simultaneous static cocultures P. aeruginosa cells killed A. fumigatus conidia, whereas the bacterial cells showed no substantial fungicidal effect on sporelings grown for 12 h or longer at 35°C. Monospecies cultures of P. aeruginosa produced loosely adhered monomicrobial biofilm and addition of 10% bovine serum to the growth medium inhibited the formation of monomicrobial biofilm by P. aeruginosa whereas it produced tightly adhered polymicrobial biofilm in the presence of A. fumigatus mycelial growth. A. fumigatus produced firmly adherent monomicrobial and polymicrobial biofilms. A comparison of CFU and MTT assays showed that the latter is unsuitable for studying the effectiveness of antimicrobial treatment against polymicrobial biofilm. Tobramycin alone and in combination with posaconazole was highly effective against monomicrobial and polymicrobial biofilms of P. aeruginosa whereas cefepime alone and in combination with posaconazole showed excellent activity against monomicrobial biofilm of P. aeruginosa but was less effective against polymicrobial

  2. Results after Late Polymicrobial, Gram-negative, and Methicillin-resistant Infections in Knee Arthroplasty

    PubMed Central

    Esteban, Jaime; García-Rey, Eduardo

    2010-01-01

    Background Previous studies of knee arthroplasty infections caused by high-virulence organisms suggest poor outcomes. Polymicrobial and Gram-negative infections are less studied. Questions/purposes This study compared the results of treatment of knee arthroplasty infections by single versus polymicrobial isolates, Gram-positive versus Gram-negative, and methicillin-resistant versus -sensitive Staphylococci. Methods We prospectively followed 47 patients with late knee arthroplasty infections. The mean age was 72 years (range, 20–87 years). The treatment protocol included two-stage exchange and a combination of two oral antibiotics given for 6 months. Minimum followup was 1 year (average, 4.8 ± 3 years; range, 1–12 years). Control of the infection was judged by absence of clinical, serologic, and radiologic signs of infection. The functional outcome was evaluated by Knee Society score at the last followup. Results Infection was controlled in all 15 patients with polymicrobial and in 28 of 32 (88%) with monomicrobial infections, in eight of nine patients with Gram-negative and in 35 of 38 (92%) with Gram-positive isolates. Control was also achieved in 22 of 25 patients (88%) infected by methicillin-resistant Staphylococci and in 14 of 14 by methicillin-sensitive Staphylococci. The Knee Society scores averaged 81-63 in patients with polymicrobial infections and were higher than in monomicrobial infections (75-52). The mean KSS was 85-59 in Gram-negative infections compared to 75-55 in Gram-positive infections. The mean KSS was similar in methicillin-resistant (78-54) and methicillin-sensitive Staphylococci (73-56) infections. Conclusions Polymicrobial and Gram-negative infections can be controlled in late knee arthroplasty infections. On the other hand, infections by methicillin-resistant Staphylococci are less likely to be controlled by the regimens we used. Level of Evidence Level II, prognostic study. See Guidelines for Authors for a complete

  3. Procalcitonin as a rapid diagnostic biomarker to differentiate between culture-negative bacterial sepsis and systemic inflammatory response syndrome: a prospective, observational, cohort study.

    PubMed

    Anand, Dimple; Das, Sabari; Bhargava, Seema; Srivastava, Lalit Mohan; Garg, Ashish; Tyagi, Niraj; Taneja, Saurabh; Ray, Sumit

    2015-02-01

    Differentiation between culture-negative sepsis and noninfectious systemic inflammatory response syndrome (SIRS) remains a diagnostic challenge for clinicians, both conditions having similar clinical presentations. Therefore, a swift accurate diagnostic tool, which helps differentiate these 2 conditions would immensely aid appropriate therapeutic continuum. This prospective study was conducted to evaluate the potential diagnostic role of biomarkers, procalcitonin (PCT) and interleukin 6 (IL-6), in culture-negative sepsis patients. Enrolled patients (208) included 46 noninfectious SIRS, 90 culture-negative sepsis, and 72 culture-positive sepsis. Culture, PCT, and IL-6 estimations were performed on day 1 of intensive care unit admission. Procalcitonin and IL-6 levels were significantly higher (P < .001) in both culture-negative and culture-positive groups as compared with SIRS group. Procalcitonin was a better predictor of sepsis in both culture-negative (area under curves 0.892 vs 0.636) and culture-positive (area under curves 0.959 vs 0.784) groups as compared with IL-6. In culture-negative group, the best cutoff point for PCT was at 1.43 ng/mL (92% sensitivity; 83% negative predictive value), best cutoff point for IL-6 was at 219.85 pg/mL (47% sensitivity and 42% negative predictive value). Procalcitonin can accurately differentiate culture-negative sepsis from noninfectious SIRS and thereby contribute to early diagnosis and effective management of these conditions. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Polymicrobial Ventilator-Associated Pneumonia: Fighting In Vitro Candida albicans-Pseudomonas aeruginosa Biofilms with Antifungal-Antibacterial Combination Therapy.

    PubMed

    Rodrigues, Maria E; Lopes, Susana P; Pereira, Cláudia R; Azevedo, Nuno F; Lourenço, Anália; Henriques, Mariana; Pereira, Maria O

    2017-01-01

    The polymicrobial nature of ventilator-associated pneumonia (VAP) is now evident, with mixed bacterial-fungal biofilms colonizing the VAP endotracheal tube (ETT) surface. The microbial interplay within this infection may contribute for enhanced pathogenesis and exert impact towards antimicrobial therapy. Consequently, the high mortality/morbidity rates associated to VAP and the worldwide increase in antibiotic resistance has promoted the search for novel therapeutic strategies to fight VAP polymicrobial infections. Under this scope, this work aimed to assess the activity of mono- vs combinational antimicrobial therapy using one antibiotic (Polymyxin B; PolyB) and one antifungal (Amphotericin B; AmB) agent against polymicrobial biofilms of Pseudomonas aeruginosa and Candida albicans. The action of isolated antimicrobials was firstly evaluated in single- and polymicrobial cultures, with AmB being more effective against C. albicans and PolyB against P. aeruginosa. Mixed planktonic cultures required equal or higher antimicrobial concentrations. In biofilms, only PolyB at relatively high concentrations could reduce P. aeruginosa in both monospecies and polymicrobial populations, with C. albicans displaying only punctual disturbances. PolyB and AmB exhibited a synergistic effect against P. aeruginosa and C. albicans mixed planktonic cultures, but only high doses (256 mg L-1) of PolyB were able to eradicate polymicrobial biofilms, with P. aeruginosa showing loss of cultivability (but not viability) at 2 h post-treatment, whilst C. albicans only started to be inhibited after 14 h. In conclusion, combination therapy involving an antibiotic and an antifungal agent holds an attractive therapeutic option to treat severe bacterial-fungal polymicrobial infections. Nevertheless, optimization of antimicrobial doses and further clinical pharmacokinetics/pharmacodynamics and toxicodynamics studies underpinning the optimal use of these drugs are urgently required to improve therapy

  5. Polymicrobial Ventilator-Associated Pneumonia: Fighting In Vitro Candida albicans-Pseudomonas aeruginosa Biofilms with Antifungal-Antibacterial Combination Therapy

    PubMed Central

    Pereira, Cláudia R.; Azevedo, Nuno F.; Lourenço, Anália; Henriques, Mariana; Pereira, Maria O.

    2017-01-01

    The polymicrobial nature of ventilator-associated pneumonia (VAP) is now evident, with mixed bacterial-fungal biofilms colonizing the VAP endotracheal tube (ETT) surface. The microbial interplay within this infection may contribute for enhanced pathogenesis and exert impact towards antimicrobial therapy. Consequently, the high mortality/morbidity rates associated to VAP and the worldwide increase in antibiotic resistance has promoted the search for novel therapeutic strategies to fight VAP polymicrobial infections. Under this scope, this work aimed to assess the activity of mono- vs combinational antimicrobial therapy using one antibiotic (Polymyxin B; PolyB) and one antifungal (Amphotericin B; AmB) agent against polymicrobial biofilms of Pseudomonas aeruginosa and Candida albicans. The action of isolated antimicrobials was firstly evaluated in single- and polymicrobial cultures, with AmB being more effective against C. albicans and PolyB against P. aeruginosa. Mixed planktonic cultures required equal or higher antimicrobial concentrations. In biofilms, only PolyB at relatively high concentrations could reduce P. aeruginosa in both monospecies and polymicrobial populations, with C. albicans displaying only punctual disturbances. PolyB and AmB exhibited a synergistic effect against P. aeruginosa and C. albicans mixed planktonic cultures, but only high doses (256 mg L-1) of PolyB were able to eradicate polymicrobial biofilms, with P. aeruginosa showing loss of cultivability (but not viability) at 2 h post-treatment, whilst C. albicans only started to be inhibited after 14 h. In conclusion, combination therapy involving an antibiotic and an antifungal agent holds an attractive therapeutic option to treat severe bacterial-fungal polymicrobial infections. Nevertheless, optimization of antimicrobial doses and further clinical pharmacokinetics/pharmacodynamics and toxicodynamics studies underpinning the optimal use of these drugs are urgently required to improve therapy

  6. [Therapy of the neurosurgical postoperative culture negative meningitis by using external lumbar drainage combined with empirical antibiotics treatment].

    PubMed

    Hong, Jian; Wu, Jianjuan; Chen, Budong; Yao, Xin; Yang, Yushan

    2016-05-01

    To evaluate the curative effect of external lumbar drainage combined with empirical antibiotics treatment on the postoperative culture negative meningitis. The clinical data of eighty post-operative meningitis patients with cerebrospinal fluid culture negative were retrospectively analyzed according to inclusive and exclusive criteria from January 2013 to December 2014 in Department of Neurosurgery, Tianjin Huanhu Hospital. All patients were composed of 45 male cases and 35 female cases, aging from 9 to 72 years. All patients were divided into two groups according to receiving the different treatment: one group only receiving a intravenously empirical antibiotics treatment (n=40), another group receiving a combined therapy of external lumbar drainage and intravenously empirical antibiotics treatment (n=40). The volume of drainage of cerebrospinal fluid (CSF) were set up from 200 to 300 ml per day. There was no difference in the dosage and interval of the same antibiotics between two groups. The antibiotics usage and therapeutic effect of two groups of patients were observed and analyzed by t-test, Wilcoxon rank test or χ(2) test. The rate of CSF bacterial culture negative was 62.9% (88/140) in the same period. In group of empirical antibiotics treatment, the time of antibiotics treatment was (12.6±3.1) days, the rate of combined with other antibiotics treatment was 40.0% (16/40), the rate of mortality was 15.0% (6/40). However, in group of external lumbar drainage combined with empirical antibiotics treatment, the 3 data were (5.3±1.2) days, 10.0% (4/40), 7.5% (3/40), respectively. The time of antibiotics of the group of empirical antibiotics was longer (t=3.605, P=0.017), while the rate of combined antibiotics and the rate of mortality were lower (χ(2)=3.971, P=0.035; χ(2)=4.136, P=0.027, respectively). The average drainage time was (5.8±1.5) days, 32 patients gained a complete healing only by their first placement, 5 cases need replacement because of

  7. Nos3 protects against systemic inflammation and myocardial dysfunction in murine polymicrobial sepsis.

    PubMed

    Bougaki, Masahiko; Searles, Robert J; Kida, Kotaro; Yu, JiaDe; Buys, Emmanuel S; Ichinose, Fumito

    2010-09-01

    NO has been implicated in the pathogenesis of septic shock. However, the role of NO synthase 3 (NOS3) during sepsis remains incompletely understood. Here, we examined the impact of NOS3 deficiency on systemic inflammation and myocardial dysfunction during peritonitis-induced polymicrobial sepsis. Severe polymicrobial sepsis was induced by colon ascendens stent peritonitis (CASP) in wild-type (WT) and NOS3-deficient (NOS3KO) mice. NOS3KO mice exhibited shorter survival time than did WT mice after CASP. NOS3 deficiency worsened systemic inflammation assessed by the expression of inflammatory cytokines in the lung, liver, and heart. Colon ascendens stent peritonitis markedly increased the number of leukocyte infiltrating the liver and heart in NOS3KO but not in WT mice. The exaggerated systemic inflammation in septic NOS3KO mice was associated with more marked myocardial dysfunction than in WT mice 22 h after CASP. The detrimental effects of NOS3 deficiency on myocardial function after CASP seem to be caused by impaired Ca handling of cardiomyocytes. The impaired Ca handling of cardiomyocytes isolated from NOS3KO mice subjected to CASP was associated with depressed mitochondrial ATP production, a determinant of the Ca cycling capacity of sarcoplasmic reticulum Ca-ATPase. The NOS3 deficiency-induced impairment of the ability of mitochondria to produce ATP after CASP was at least in part attributable to reduction in mitochondrial respiratory chain complex I activity. These observations suggest that NOS3 protects against systemic inflammation and myocardial dysfunction after peritonitis-induced polymicrobial sepsis in mice.

  8. NOS3 protects against systemic inflammation and myocardial dysfunction in murine polymicrobial sepsis

    PubMed Central

    Bougaki, Masahiko; Searles, Robert J.; Kida, Kotaro; De Yu, Jia; Buys, Emmanuel S.; Ichinose, Fumito

    2013-01-01

    Nitric oxide (NO) has been implicated in the pathogenesis of septic shock. However, the role of NO synthase 3 (NOS3) during sepsis remains incompletely understood. Here, we examined impact of NOS3 deficiency on systemic inflammation and myocardial dysfunction during peritonitis-induced polymicrobial sepsis. Severe polymicrobial sepsis was induced by colon ascendens stent peritonitis (CASP) in wild-type (WT) and NOS3-deficient (NOS3KO) mice. NOS3KO mice exhibited shorter survival time than did WT mice after CASP. NOS3 deficiency worsened systemic inflammation assessed by the expression of inflammatory cytokines in the lung, liver, and heart. CASP markedly increased the number of leukocyte infiltrating the liver and heart in NOS3KO but not in WT mice. The exaggerated systemic inflammation in septic NOS3KO mice was associated with more marked myocardial dysfunction than in WT mice 22h after CASP. The detrimental effects of NOS3-deficiency on myocardial function after CASP appear to be caused by impaired Ca2+ handling of cardiomyocytes. The impaired Ca2+ handling of cardiomyocytes isolated from NOS3KO mice subjected to CASP was associated with depressed mitochondrial ATP production, a determinant of the Ca2+ cycling capacity of sarcoplasmic reticulum (SR) Ca2+-ATPase. The NOS3-deficiency-induced impairment of the ability of mitochondria to produce ATP after CASP was at least in part attributable to reduction in mitochondrial respiratory chain complex I activity. These observations suggest that NOS3 protects against systemic inflammation and myocardial dysfunction after peritonitis-induced polymicrobial sepsis in mice. PMID:19997049

  9. Synergy in Polymicrobial Infections in a Mouse Model of Type 2 Diabetes†

    PubMed Central

    Mastropaolo, Matthew D.; Evans, Nicholas P.; Byrnes, Meghan K.; Stevens, Ann M.; Robertson, John L.; Melville, Stephen B.

    2005-01-01

    Human diabetics frequently suffer delayed wound healing, increased susceptibility to localized and systemic infections, and limb amputations as a consequence of the disease. Lower-limb infections in diabetic patients are most often polymicrobial, involving mixtures of aerobic, facultative anaerobic, and anaerobic bacteria. The purpose of this study is to determine if these organisms contribute to synergy in polymicrobial infections by using diabetic mice as an in vivo model. The model was the obese diabetic mouse strain BKS.Cg-m +/+ Leprdb/J, a model of human type 2 diabetes. Young (5- to 6-week-old) prediabetic mice and aged (23- to 24-week-old) diabetic mice were compared. The mice were injected subcutaneously with mixed cultures containing Escherichia coli, Bacteroides fragilis, and Clostridium perfringens. Progression of the infection (usually abscess formation) was monitored by examining mice for bacterial populations and numbers of white blood cells at 1, 8, and 22 days postinfection. Synergy in the mixed infections was defined as a statistically significant increase in the number of bacteria at the site of injection when coinfected with a second bacterium, compared to when the bacterium was inoculated alone. E. coli provided strong synergy to B. fragilis but not to C. perfringens. C. perfringens and B. fragilis provided moderate synergy to each other but only in young mice. B. fragilis was anergistic (antagonistic) to E. coli in coinfections in young mice at 22 days postinfection. When age-matched nondiabetic mice (C57BLKS/J) were used as controls, the diabetic mice exhibited 5 to 35 times the number of CFU as did the nondiabetic mice, indicating that diabetes was a significant factor in the severity of the polymicrobial infections. PMID:16113326

  10. Draft Genome Sequences of Four Bacterial Strains Isolated from a Polymicrobial Culture of Naked (N-Type) Emiliania huxleyi CCMP1516

    PubMed Central

    Orata, Fabini D.; Rosana, Albert Remus R.; Xu, Yue; Simkus, Danielle N.; Bramucci, Anna R.; Boucher, Yan

    2016-01-01

    Strains of Sulfitobacter spp., Erythrobacter sp., and Marinobacter sp. were isolated from a polymicrobial culture of the naked (N-type) haptophyte Emiliania huxleyi strain CCMP1516. The genomes encode genes for the production of phytohormones, vitamins, and the consumption of their hosts’ metabolic by-products, suggesting symbiotic interactions within this polymicrobial culture. PMID:27417846

  11. Draft Genome Sequences of Seven Bacterial Strains Isolated from a Polymicrobial Culture of Coccolith-Bearing (C-Type) Emiliania huxleyi M217

    PubMed Central

    Rosana, Albert Remus R.; Orata, Fabini D.; Xu, Yue; Simkus, Danielle N.; Bramucci, Anna R.; Boucher, Yan

    2016-01-01

    Strains of Rhodobacteraceae, Sphingomonadales, Alteromonadales, and Bacteroidetes were isolated from a polymicrobial culture of the coccolith-forming (C-type) haptophyte Emiliania huxleyi strain M217. The genomes encode genes for the production of algal growth factors and the consumption of their hosts’ metabolic by-products, suggesting that the polymicrobial culture harbors many symbiotic interactions. PMID:27417845

  12. Success rates of first-line antibiotics for culture-negative sub-acute and chronic septic arthritis.

    PubMed

    Chuckpaiwong, Bavornrit; Phoompoung, Saravut

    2014-09-01

    A combination of surgical and medical treatment is normally required for patients with septic arthritis. Antibiotics selected for use on these patients are normally based on tissue culture results. However, in sub-acute and chronic septic arthritis cases, the results of the culture are usually negative as a result of prior treatment. The present study will investigate the incidence of culture-negative septic arthritis and the outcomes based on the use of first-line drug antibiotics for the treatment of sub-acute and chronic septic arthritis. For the present study, the authors retrospectively reviewed medical records of surgically treated septic arthritis cases over the past 10 years at Siriraj Hospital. The patient culture results, the antibiotics used, and the results of treatment were all recorded and analyzed. One hundredfifty-three septic arthritis patients were reviewed. Sixty-two patients were classified as having been diagnosed with either sub-acute or chronic septic arthritis. Thirty-six of 62 patients (58.1%) had a negative culture result. In the culture-positive patients, 42.3% had Streptococcus, 26.9% had Staphylococcus aureus, 11.5% had other gram positive bacteria, 15.4% had gram-negative bacteria, and 3.8% had tuberculus infection. In the culture-negative sub-acute and chronic group (36 of 62), 23 patients received Cefazolin, nine patients received Cloxacillin, and four patients received Clindamycin. Successful results were 69.9%, 66.7% and 75%, respectively. The present study reflects that the incidence ofculture-negative, sub-acute and chronic septic arthritis is approximately 58.1%. The first-line class of antibiotics remains the appropriate antibiotic choice for these patients because they are still effective for treatment of septic arthritis in up to 70% of all cases.

  13. Modulatory Effects of Astragalus Polysaccharides on T-Cell Polarization in Mice with Polymicrobial Sepsis

    PubMed Central

    Hou, Yu-Chen; Wu, Jin-Ming; Wang, Ming-Yang; Wu, Ming-Hsun; Chen, Kuen-Yuan; Yeh, Sung-Ling; Lin, Ming-Tsan

    2015-01-01

    Background. This study evaluated the impact of different doses of Astragalus polysaccharides (APS) on the functional status and phenotype of T cells during polymicrobial sepsis. Methods. On day 1 after cecal ligation and puncture, mice were treated with either saline, 100 (A100), 200 (A200), or 400 mg APS/kg body weight (BW) (A400) by an intraperitoneal injection daily for 4 days. All mice were sacrificed 5 days after the operation. Results. APS treatment reversed the sepsis-induced decrement in the T helper (Th) cell population, and the percentage of activated Th cells also increased in the spleen and Peyer's patches. APS administration downregulated the percentages of circulating Th2 cells and regulatory T cells (Treg), and the percentage of Th17 cells in blood was upregulated in the A400 group. Weight loss and kidney injury were attenuated in the A100 and A200 groups but not in the A400 group at the end of the study. Conclusions. Treatments with 100 and 200 mg APS/kg BW reduced Treg populations and elicited a more-balanced Th1/Th2 response that consequently attenuated immunosuppression in polymicrobial sepsis. High-dose APS administration led to excessive responses of Th17 cells which may have adverse effects in sepsis-induced organ injury. PMID:26693207

  14. Combining ANOVA-PCA with POCHEMON to analyse micro-organism development in a polymicrobial environment.

    PubMed

    Geurts, Brigitte P; Neerincx, Anne H; Bertrand, Samuel; Leemans, Manja A A P; Postma, Geert J; Wolfender, Jean-Luc; Cristescu, Simona M; Buydens, Lutgarde M C; Jansen, Jeroen J

    2017-04-22

    Revealing the biochemistry associated to micro-organismal interspecies interactions is highly relevant for many purposes. Each pathogen has a characteristic metabolic fingerprint that allows identification based on their unique multivariate biochemistry. When pathogen species come into mutual contact, their co-culture will display a chemistry that may be attributed both to mixing of the characteristic chemistries of the mono-cultures and to competition between the pathogens. Therefore, investigating pathogen development in a polymicrobial environment requires dedicated chemometric methods to untangle and focus upon these sources of variation. The multivariate data analysis method Projected Orthogonalised Chemical Encounter Monitoring (POCHEMON) is dedicated to highlight metabolites characteristic for the interaction of two micro-organisms in co-culture. However, this approach is currently limited to a single time-point, while development of polymicrobial interactions may be highly dynamic. A well-known multivariate implementation of Analysis of Variance (ANOVA) uses Principal Component Analysis (ANOVA-PCA). This allows the overall dynamics to be separated from the pathogen-specific chemistry to analyse the contributions of both aspects separately. For this reason, we propose to integrate ANOVA-PCA with the POCHEMON approach to disentangle the pathogen dynamics and the specific biochemistry in interspecies interactions. Two complementary case studies show great potential for both liquid and gas chromatography - mass spectrometry to reveal novel information on chemistry specific to interspecies interaction during pathogen development.

  15. Enterococcus faecalis promotes innate immune suppression and polymicrobial catheter-associated urinary tract infection.

    PubMed

    Tien, Brenda Yin Qi; Goh, Hwee Mian Sharon; Chong, Kelvin Kian Long; Bhaduri-Tagore, Soumili; Holec, Sarah; Dress, Regine; Ginhoux, Florent; Ingersoll, Molly A; Williams, Rohan B H; Kline, Kimberly A

    2017-09-11

    Enterococcus faecalis, a member of the human gastrointestinal microbiota, is an opportunistic pathogen associated with hospital-acquired wound, bloodstream, and urinary tract infections. E. faecalis can subvert or evade immune-mediated clearance, although the mechanisms are poorly understood. In this study, we examined E. faecalis-mediated subversion of macrophage activation. We observed that E. faecalis actively prevents NF-κB signaling in mouse RAW264.7 macrophages in the presence of Toll-like receptor agonists and during polymicrobial infection with Escherichia coliE. faecalis and E. coli co-infection in a mouse model of catheter-associated urinary tract infection (CAUTI) resulted in a suppressed macrophage transcriptional response in the bladder compared to E. coli infection alone. Finally, we demonstrated that co-inoculation of E. faecalis with a commensal strain of E. coli into catheterized bladders significantly augmented E. coli CAUTI. Taken together, these results support that E. faecalis suppression of NF-κB-driven responses in macrophages promotes polymicrobial CAUTI pathogenesis especially when co-infected with less virulent or commensal E. coli strains. Copyright © 2017 American Society for Microbiology.

  16. From metabolism to ecology: cross-feeding interactions shape the balance between polymicrobial conflict and mutualism.

    PubMed

    Estrela, Sylvie; Trisos, Christopher H; Brown, Sam P

    2012-11-01

    Polymicrobial interactions are widespread in nature and play a major role in maintaining human health and ecosystems. Whenever one organism uses metabolites produced by another organism as energy or nutrient sources, it is called cross-feeding. The ecological outcomes of cross-feeding interactions are poorly understood and potentially diverse: mutualism, competition, exploitation, or commensalism. A major reason for this uncertainty is the lack of theoretical approaches linking microbial metabolism to microbial ecology. To address this issue, we explore the dynamics of a one-way interspecific cross-feeding interaction in which food can be traded for a service (detoxification). Our results show that diverse ecological interactions (competition, mutualism, exploitation) can emerge from this simple cross-feeding interaction and can be predicted by the metabolic, demographic, and environmental parameters that govern the balance of the costs and benefits of association. In particular, our model predicts stronger mutualism for intermediate by-product toxicity because the resource-service exchange is constrained to the service being neither too vital (high toxicity impairs resource provision) nor dispensable (low toxicity reduces need for service). These results support the idea that bridging microbial ecology and metabolism is a critical step toward a better understanding of the factors governing the emergence and dynamics of polymicrobial interactions.

  17. Polymicrobial Pituitary Abscess Predominately Involving Escherichia coli in the Setting of an Apoplectic Pituitary Prolactinoma

    PubMed Central

    Beatty, Norman; Medina-Garcia, Luis; Al Mohajer, Mayar; Zangeneh, Tirdad T.

    2016-01-01

    Pituitary abscess is a rare intracranial infection that can be life-threatening if not appropriately diagnosed and treated upon presentation. The most common presenting symptoms include headache, anterior pituitary hypofunction, and visual field disturbances. Brain imaging with either computed tomography or magnetic resonance imaging usually reveals intra- or suprasellar lesion(s). Diagnosis is typically confirmed intra- or postoperatively when pathological analysis is done. Clinicians should immediately start empiric antibiotics and request a neurosurgical consult when pituitary abscess is suspected. Escherichia coli (E. coli) causing intracranial infections are not well understood and are uncommon in adults. We present an interesting case of an immunocompetent male with a history of hypogonadism presenting with worsening headache and acute right eye vision loss. He was found to have a polymicrobial pituitary abscess predominantly involving E.   coli in addition to Actinomyces odontolyticus and Prevotella melaninogenica in the setting of an apoplectic pituitary prolactinoma. The definitive etiology of this infection was not determined but an odontogenic process was suspected. A chronic third molar eruption and impaction in close proximity to the pituitary gland likely led to contiguous spread of opportunistic oral microorganisms allowing for a polymicrobial pituitary abscess formation. PMID:27006841

  18. Cyanide Toxicity to Burkholderia cenocepacia Is Modulated by Polymicrobial Communities and Environmental Factors

    PubMed Central

    Bernier, Steve P.; Workentine, Matthew L.; Li, Xiang; Magarvey, Nathan A.; O'Toole, George A.; Surette, Michael G.

    2016-01-01

    Microbes within polymicrobial communities can establish positive and negative interactions that have the potential to influence the overall behavior of the community. Pseudomonas aeruginosa and species of the Burkholderia cepacia complex (Bcc) can co-exist in the lower airways, however several studies have shown that P. aeruginosa can effectively kill the Bcc in vitro, for which hydrogen cyanide (HCN) was recently proposed to play a critical role. Here we show that modification of the environment (i.e., culture medium), long-term genetic adaptation of P. aeruginosa to the cystic fibrosis (CF) lung, or the addition of another bacterial species to the community can alter the sensitivity of Burkholderia cenocepacia to P. aeruginosa toxins. We specifically demonstrate that undefined rich media leads to higher susceptibility of B. cenocepacia to P. aeruginosa toxins like cyanide as compared to a synthetic medium (SCFM), that mimics the CF lung nutritional content. Overall, our study shows that the polymicrobial environment can have profound effects on negative interactions mediated by P. aeruginosa against B. cenocepacia. In fact, evolved P. aeruginosa or the presence of other species such as Staphylococcus aureus can directly abolish the direct competition mediated by cyanide and consequently maintaining a higher level of species diversity within the community. PMID:27242743

  19. Polymicrobial biofilm formation by Candida albicans, Actinomyces naeslundii, and Streptococcus mutans is Candida albicans strain and medium dependent.

    PubMed

    Arzmi, Mohd Hafiz; Alnuaimi, Ali D; Dashper, Stuart; Cirillo, Nicola; Reynolds, Eric C; McCullough, Michael

    2016-11-01

    Oral biofilms comprise of extracellular polysaccharides and polymicrobial microorganisms. The objective of this study was to determine the effect of polymicrobial interactions of Candida albicans, Actinomyces naeslundii, and Streptococcus mutans on biofilm formation with the hypotheses that biofilm biomass and metabolic activity are both C. albicans strain and growth medium dependent. To study monospecific biofilms, C. albicans, A. naeslundii, and S. mutans were inoculated into artificial saliva medium (ASM) and RPMI-1640 in separate vials, whereas to study polymicrobial biofilm formation, the inoculum containing microorganisms was prepared in the same vial prior inoculation into a 96-well plate followed by 72 hours incubation. Finally, biofilm biomass and metabolic activity were measured using crystal violet and XTT assays, respectively. Our results showed variability of monospecies and polymicrobial biofilm biomass between C. albicans strains and growth medium. Based on cut-offs, out of 32, seven RPMI-grown biofilms had high biofilm biomass (HBB), whereas, in ASM-grown biofilms, 14 out of 32 were HBB. Of the 32 biofilms grown in RPMI-1640, 21 were high metabolic activity (HMA), whereas in ASM, there was no biofilm had HMA. Significant differences were observed between ASM and RPMI-grown biofilms with respect to metabolic activity (P <01). In conclusion, biofilm biomass and metabolic activity were both C. albicans strain and growth medium dependent. © The Author 2016. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Importance of Toll-like Receptor 2 in Mitochondrial Dysfunction during Polymicrobial Sepsis

    PubMed Central

    Gong, Yu; Zou, Lin; Feng, Yan; Li, Dan; Cai, Jiayan; Chen, Dunjin; Chao, Wei

    2014-01-01

    BACKGROUND Toll-like receptor 2 (TLR2) contributes to sepsis pathogenesis such as deleterious systemic inflammation, cardiac dysfunction, and high mortality in animal studies. Mitochondrial dysfunction is a key molecular event that is associated with organ injury in sepsis. The role of TLR2 in sepsis-induced mitochondrial dysfunction remains unclear. METHODS Intracellular hydrogen peroxide (H2O2) and mitochondrial superoxide (O2−), mitochondrial membrane potential (ΔΨm) and intracellular adenosine triphosphate (ATP) were measured in peritoneal leukocytes. A mouse model of polymicrobial sepsis was generated by cecum ligation and puncture (CLP). Wild-type and TLR2-deficient (TLR2−/−) mice were subjected to sham or CLP. Mitochondrial functions including reactive oxygen species (ROS), ΔΨm, intracellular ATP, and complex III activity were measured. RESULTS TLR2/1 activation by Pam3Cys enhanced intracellular H2O2 and mitochondrial O2- production in leukocytes, but had no effect on mitochondrial ΔΨm and ATP production. The effect was specific for TLR2/1 as TLR3 or TLR9 ligands did not induce ROS production. Polymicrobial sepsis induced mitochondrial dysfunction in leukocytes, as demonstrated by increased H2O2 and mitochondrial O2− production (CLP vs. sham; H2O2: 3,173 ± 498, n = 5 vs. 557 ± 38, n = 4; O2−: 707 ± 66, n = 35 vs. 485 ± 35, n = 17, mean fluorescence intensity, mean ± SEM), attenuated complex III activity (13 ± 2, n = 16 vs. 30 ± 3, n = 7, milli-optical densities per minute, mOD/min), loss of mitochondrial ΔΨm, and depletion of intracellular ATP (33 ± 6, n = 11 vs. 296 ± 29, n = 4, nmol/mg protein). In comparison, there was significant improvement in mitochondrial function in septic TLR2−/− mice as evidenced by attenuated mitochondrial ROS production, better- maintained mitochondrial ΔΨm and higher cellular ATP production. CONCLUSIONS TLR2 signaling plays a critical role in mediating mitochondrial dysfunction in peritoneal

  1. Fish Oil-Based Fat Emulsion Reduces Acute Kidney Injury and Inflammatory Response in Antibiotic-Treated Polymicrobial Septic Mice.

    PubMed

    Shih, Juey-Ming; Shih, Yao-Ming; Pai, Man-Hui; Hou, Yu-Chen; Yeh, Chiu-Li; Yeh, Sung-Ling

    2016-03-15

    Acute kidney injury (AKI) is a common complication in sepsis. This study compared the effects of a fish oil-based with a mixed oil fat emulsion on remote renal injury in an antibiotic-treated septic murine model. Mice were randomly assigned to a normal control (NC) group and three septic groups. Sepsis was induced by cecal ligation and puncture (CLP). The antibiotic was injected intraperitoneally (IP) after CLP and then daily till the time of sacrifice. Three hours after antibiotic treatment, one of the septic groups was injected IP with a fish oil-based emulsion (FO), while the other two groups were given either a mixed oil emulsion (MO) or saline (SC). The septic groups were further divided into two separate time groups, with blood and kidneys samples collected at 24 h or 72 h post-CLP. The results showed that sepsis leads to the activation of neutrophils, T helper (Th)1/Th-2/Th-17 and Treg cells (p < 0.05). Plasma NGAL and mRNA expressions of renal MyD88 and TLR4 were also enhanced (p < 0.05). Compared to the SC group, the group given the fish oil-based emulsion had decreased plasma NGAL by 22% and Treg by 33%. Furthermore, renal gene expressions of MyD88 and TLR4 reduced by 46% and 62%, respectively, whereas heat shock protein 70 and peroxisome proliferator-activated receptor-γ increased by 158% and 69%, respectively (p < 0.05), at Day 3 after CLP. These results suggest that administration of a fish oil-based emulsion has favorable effects, maintaining blood T cell percentage, downregulating Treg expression, attenuating systemic and local inflammation and offering renal protection under conditions of antibiotic-treated polymicrobial sepsis.

  2. Aerococcus christensenii native aortic valve subacute bacterial endocarditis (SBE) presenting as culture negative endocarditis (CNE) mimicking marantic endocarditis.

    PubMed

    Jose, Anita; Cunha, Burke A; Klein, Natalie C; Schoch, Paul E

    2014-01-01

    This is a case report of an adult who presented with apparent culture negative endocarditis (CNE) thought to be marantic endocarditis due to a B-cell lymphoproliferative disorder. This was a most perplexing case and was eventually diagnosed as subacute bacterial endocarditis (SBE) due to a rare slow growing organism. Against the diagnosis of SBE was the lack of fever, hepatomegaly, peripheral manifestations and microscopic hematuria. Also, against a diagnosis of SBE was another explanation for the patient's abnormal findings, e.g., elevated ferritin levels, elevated α1/α2 globulins on SPEP, an elevated alkaline phosphatase, flow cytometry showing B-lymphocytes expressing CD5, and a bone lesion in the right iliac. Findings compatible with both SBE and marantic endocarditis due to a B-cell lymphoproliferative disorder included an elevated ESR, and splenomegaly. Blood cultures eventually became positive during hospitalization. We report a case of native aortic valve (AV) subacute bacterial endocarditis (SBE) due to Aerococcus christensenii mimicking marantic endocarditis due to a B-cell lymphoproliferative disorder. To the best of our knowledge, this is the first reported case of native AV SBE due to A. christensenii presenting as marantic endocarditis.

  3. Gonorrhoea Diagnostic and Treatment Uncertainties: Risk Factors for Culture Negative Confirmation after Positive Nucleic Acid Amplification Tests.

    PubMed

    Vyth, Rebecka; Leval, Amy; Eriksson, Björn; Ericson, Eva-Lena; Marions, Lena; Hergens, Maria-Pia

    2016-01-01

    Gonorrhoea incidence has increased substantially in Stockholm during the past years. These increases have coincided with changes in testing practice from solely culture-based to nucleic acid amplification tests (NAAT). Gonorrhoea NAAT is integrated with Chlamydia trachomatis testing and due to opportunistic screening for chlamydia, testing prevalence for gonorrhoea has increased substantially in the Stockholm population. The aim of this study was to examine epidemiological risk-factors for discordant case which are NAAT positive but culture negative. These discordant cases are especially problematic as they give rise to diagnostic and treatment uncertainties with risk for subsequent sequelae. All gonorrhoea cases from Stockholm county during 2011-2012 with at least one positive N. gonorrhoea NAAT test and follow-up cultures were included (N = 874). Data were analysed using multivariate and stratified logistic regression models. Results showed that women were 4-times more likely (OR 4.9; 95% CI 2.4-6.7) than men to have discordant cultures. Individuals tested for gonorrhoea without symptoms were 2.3 times more likely (95% CI 1.5-3.5) than those with symptoms to be discordant. NAAT method and having one week or more between NAAT and culture testing were also indicative of an increased likelihood for discordance. Using NAAT should be based on proper clinical or epidemiological indications and, when positive, followed-up with a culture-based test within one week if possible. Routine gonorrhoea testing is not recommended in low prevalence populations.

  4. Mean platelet volume as a novel predictor of systemic inflammatory response in cirrhotic patients with culture-negative neutrocytic ascites

    PubMed Central

    Gálvez-Martínez, Marisol; Servín-Caamaño, Alfredo I; Pérez-Torres, Eduardo; Salas-Gordillo, Francisco; Rivera-Gutiérrez, Xaira; Higuera-de la Tijera, Fátima

    2015-01-01

    AIM: To identify a mean platelet volume (MPV) cutoff value which should be able to predict the presence of bacterial infection. METHODS: An observational, analytic, retrospective study. We evaluated medical records of cirrhotic patients who were hospitalized from January 2012 to January 2014 at the Gastroenterology Department of “Hospital General de México Dr. Eduardo Liceaga”, we included 51 cirrhotic patients with ascites fluid infection (AFI), and 50 non-infected cirrhotic patients as control group. Receiver operator characteristic curves were used to identify the best cutoff value of several parameters from hematic cytometry, including MPV, to predict the presence of ascites fluid infection. RESULTS: Of the 51 cases with AFI, 48 patients (94.1%) had culture-negative neutrocytic ascites (CNNA), 2 (3.9%) had bacterial ascites, and one (2%) had spontaneous bacterial peritonitis. Infected patients had greater count of leucocytes and polymorphonuclear cells, greater levels of MPV and cardiac frequency (P < 0.0001), and lower mean arterial pressure compared with non-infected patients (P = 0.009). Leucocytes, polymorphonuclear count, MPV and cardiac frequency resulted to be good or very good predictive variables of presence of AFI in cirrhotic patients (area under the receiving operating characteristic > 0.80). A cutoff MPV value of 8.3 fl was the best to discriminate between cirrhotic patients with AFI and those without infection. CONCLUSION: Our results support that MPV can be an useful predictor of systemic inflammatory response syndrome in cirrhotic patients with AFI, particularly CNNA. PMID:25954482

  5. Mean platelet volume as a novel predictor of systemic inflammatory response in cirrhotic patients with culture-negative neutrocytic ascites.

    PubMed

    Gálvez-Martínez, Marisol; Servín-Caamaño, Alfredo I; Pérez-Torres, Eduardo; Salas-Gordillo, Francisco; Rivera-Gutiérrez, Xaira; Higuera-de la Tijera, Fátima

    2015-05-08

    To identify a mean platelet volume (MPV) cutoff value which should be able to predict the presence of bacterial infection. An observational, analytic, retrospective study. We evaluated medical records of cirrhotic patients who were hospitalized from January 2012 to January 2014 at the Gastroenterology Department of "Hospital General de México Dr. Eduardo Liceaga", we included 51 cirrhotic patients with ascites fluid infection (AFI), and 50 non-infected cirrhotic patients as control group. Receiver operator characteristic curves were used to identify the best cutoff value of several parameters from hematic cytometry, including MPV, to predict the presence of ascites fluid infection. Of the 51 cases with AFI, 48 patients (94.1%) had culture-negative neutrocytic ascites (CNNA), 2 (3.9%) had bacterial ascites, and one (2%) had spontaneous bacterial peritonitis. Infected patients had greater count of leucocytes and polymorphonuclear cells, greater levels of MPV and cardiac frequency (P < 0.0001), and lower mean arterial pressure compared with non-infected patients (P = 0.009). Leucocytes, polymorphonuclear count, MPV and cardiac frequency resulted to be good or very good predictive variables of presence of AFI in cirrhotic patients (area under the receiving operating characteristic > 0.80). A cutoff MPV value of 8.3 fl was the best to discriminate between cirrhotic patients with AFI and those without infection. Our results support that MPV can be an useful predictor of systemic inflammatory response syndrome in cirrhotic patients with AFI, particularly CNNA.

  6. Adrenergic modulation of cytokine release in bone marrow progenitor-derived macrophage following polymicrobial sepsis.

    PubMed

    Muthu, Kuzhali; Deng, Jiangping; Gamelli, Richard; Shankar, Ravi; Jones, Stephen B

    2005-01-01

    Catecholamines may impact on the pathophysiology of sepsis by attenuating proinflammatory cytokine and augmenting antiinflammatory cytokine production by macrophages. We tested this premise in bone marrow monocyte progenitor-derived macrophages. Polymicrobial sepsis was induced in mice through cecal ligation and puncture. ER-MP 12 monocyte progenitors were isolated and differentiated into macrophages in vitro 72 hr later. Lipopolysaccharide (LPS)-stimulated cytokine production was measured with and without epinephrine, IL-10 and anti-IL-10 antibody. Epinephrine significantly increased IL-10 production, but attenuated TNF-alpha release exclusively through beta2 adrenergic receptors, and is independent of IL-10 production. Together, these results suggest that epinephrine can promote a potent antiinflammatory response in sepsis.

  7. Treatment of Polymicrobial Osteomyelitis with Ceftolozane-Tazobactam: Case Report and Sensitivity Testing of Isolates

    PubMed Central

    Jolliff, Jeffrey C.; Joson, Jeremiah; Heidari, Arash; Johnson, Royce

    2016-01-01

    Stenotrophomonas maltophilia is an inherently multidrug resistant (MDR) opportunistic pathogen with many mechanisms of resistance. SENTRY studies reveal decreasing sensitivities of S. maltophilia to trimethoprim-sulfamethoxazole and fluoroquinolones. Ceftolozane-tazobactam (Zerbaxa, Merck & Co., Inc.) a novel intravenous combination agent of a third-generation cephalosporin and β-lactamase inhibitor was demonstrated to have in vitro activity against many Gram-positive, Gram-negative, and MDR organisms. Data for ceftolozane-tazobactam's use outside of Food and Drug Administration (FDA) approved indications has been limited thus far to two case reports which demonstrated its efficacy in pan-resistant Pseudomonas aeruginosa pneumonia. Herein, we describe the first published case of treatment of MDR S. maltophilia in polymicrobial osteomyelitis with long-term (>14 days) ceftolozane-tazobactam and metronidazole. Ceftolozane-tazobactam may offer a possible alternative for clinicians faced with limited options in the treatment of resistant pathogens including MDR S. maltophilia. PMID:27437155

  8. Chemical chaperone TUDCA prevents apoptosis and improves survival during polymicrobial sepsis in mice

    PubMed Central

    Doerflinger, Marcel; Glab, Jason; Nedeva, Christina; Jose, Irvin; Lin, Ann; O’Reilly, Lorraine; Allison, Cody; Pellegrini, Marc; Hotchkiss, Richard S.; Puthalakath, Hamsa

    2016-01-01

    Sepsis-induced lymphopenia is a major cause of morbidities in intensive care units and in populations with chronic conditions such as renal failure, diabetes, HIV and alcohol abuse. Currently, other than supportive care and antibiotics, there are no treatments for this condition. We developed an in vitro assay to understand the role of the ER-stress-mediated apoptosis process in lymphocyte death during polymicrobial sepsis, which was reproducible in in vivo mouse models. Modulating ER stress using chemical chaperones significantly reduced the induction of the pro-apoptotic protein Bim both in vitro and in mice. Furthermore, in a ‘two-hit’ pneumonia model in mice, we have been able to demonstrate that administration of the chemical chaperone TUDCA helped to maintain lymphocyte homeostasis by significantly reducing lymphocyte apoptosis and this correlated with four-fold improvement in survival. Our results demonstrate a novel therapeutic opportunity for treating sepsis-induced lymphopenia in humans. PMID:27694827

  9. Contact Lens-related Polymicrobial Keratitis from Pantoea agglomerans and Escherichia vulneris.

    PubMed

    Venincasa, Vincent D; Callegan, Michelle; Astley, Roger A; Siatkowski, R Michael

    2016-04-01

    To report a case of polymicrobial keratitis caused by Panotea agglomerans, Escherichia vulneris and coagulase-negative Staphylococcus in a patient who cleaned their extended wear contact lenses with only tap water for 2 weeks. Case report. An adult presented with a painful red eye after wearing the same contact lenses for two weeks. The patient admitted to taking the contacts out in the evening and cleaning them with tap water before reapplying them in the morning. Exam revealed a 2.5 mm paracentral corneal ulcer in the left eye. Culture results from corneal scrapings were positive for Panotea agglomerans, Escherichia vulneris and coagulase-negative Staphylococcus. This is the first report of Panotea agglomerans and Escherichia vulneris keratitis in association with contact lens wear. Both strains of Panotea agglomerans and Escherichia vulneris were pansensitive to all tested antibiotics.

  10. Gram-Positive Uropathogens, Polymicrobial Urinary Tract Infection, and the Emerging Microbiota of the Urinary Tract.

    PubMed

    Kline, Kimberly A; Lewis, Amanda L

    2016-04-01

    Gram-positive bacteria are a common cause of urinary-tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for UTI. Here we review the epidemiology, virulence mechanisms, and host response to the most frequently isolated Gram-positive uropathogens: Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae. We also review several emerging, rare, misclassified, and otherwise underreported Gram-positive pathogens of the urinary tract including Aerococcus, Corynebacterium, Actinobaculum, and Gardnerella. The literature strongly suggests that urologic diseases involving Gram-positive bacteria may be easily overlooked due to limited culture-based assays typically utilized for urine in hospital microbiology laboratories. Some UTIs are polymicrobial in nature, often involving one or more Gram-positive bacteria. We herein review the risk factors and recent evidence for mechanisms of bacterial synergy in experimental models of polymicrobial UTI. Recent experimental data has demonstrated that, despite being cleared quickly from the bladder, some Gram-positive bacteria can impact pathogenic outcomes of co-infecting organisms. When taken together, the available evidence argues that Gram-positive bacteria are important uropathogens in their own right, but that some can be easily overlooked because they are missed by routine diagnostic methods. Finally, a growing body of evidence demonstrates that a surprising variety of fastidious Gram-positive bacteria may either reside in or be regularly exposed to the urinary tract and further suggests that their presence is widespread among women, as well as men. Experimental studies in this area are needed; however, there is a growing appreciation that the composition of bacteria found in the bladder could be a potentially important determinant in urologic disease, including susceptibility to UTI.

  11. Impact of Mucorales and Other Invasive Molds on Clinical Outcomes of Polymicrobial Traumatic Wound Infections.

    PubMed

    Warkentien, Tyler E; Shaikh, Faraz; Weintrob, Amy C; Rodriguez, Carlos J; Murray, Clinton K; Lloyd, Bradley A; Ganesan, Anuradha; Aggarwal, Deepak; Carson, M Leigh; Tribble, David R

    2015-07-01

    Combat trauma wounds with invasive fungal infections (IFIs) are often polymicrobial with fungal and bacterial growth, but the impact of the wound microbiology on clinical outcomes is uncertain. Our objectives were to compare the microbiological features between IFI and non-IFI wounds and evaluate whether clinical outcomes differed among IFI wounds based upon mold type. Data from U.S. military personnel injured in Afghanistan with IFI wounds were examined. Controls were matched by the pattern/severity of injury, including blood transfusion requirements. Wound closure timing was compared between IFI and non-IFI control wounds (with/without bacterial infections). IFI wound closure was also assessed according to mold species isolation. Eighty-two IFI wounds and 136 non-IFI wounds (63 with skin and soft tissue infections [SSTIs] and 73 without) were examined. The time to wound closure was longer for the IFI wounds (median, 16 days) than for the non-IFI controls with/without SSTIs (medians, 12 and 9 days, respectively; P < 0.001). The growth of multidrug-resistant Gram-negative rods was reported among 35% and 41% of the IFI and non-IFI wounds with SSTIs, respectively. Among the IFI wounds, times to wound closure were significantly longer for wounds with Mucorales growth than for wounds with non-Mucorales growth (median, 17 days versus 13 days; P < 0.01). When wounds with Mucorales and Aspergillus spp. growth were compared, there was no significant difference in wound closure timing. Trauma wounds with SSTIs were often polymicrobial, yet the presence of invasive molds (predominant types: order Mucorales, Aspergillus spp., and Fusarium spp.) significantly prolonged the time to wound closure. Overall, the times to wound closure were longest for the IFI wounds with Mucorales growth. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  12. Gram-Positive Uropathogens, Polymicrobial Urinary Tract Infection, and the Emerging Microbiota of the Urinary Tract

    PubMed Central

    Kline, Kimberly A.; Lewis, Amanda L.

    2015-01-01

    Gram-positive bacteria are a common cause of urinary tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for UTI. Here we review the epidemiology, virulence mechanisms, and host response to the most frequently isolated Gram-positive uropathogens: Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae. We also review several emerging, rare, misclassified, and otherwise underreported Gram-positive pathogens of the urinary tract including Aerococcus, Corynebacterium, Actinobaculum, and Gardnerella. The literature strongly suggests that urologic diseases involving Gram-positive bacteria may be easily overlooked due to limited culture-based assays typically utilized for urine in hospital microbiology laboratories. Some UTIs are polymicrobial in nature, often involving one or more Gram-positive bacteria. We herein review the risk factors and recent evidence for mechanisms of bacterial synergy in experimental models of polymicrobial UTI. Recent experimental data has demonstrated that, despite being cleared quickly from the bladder, some Gram-positive bacteria can impact pathogenic outcomes of co-infecting organisms. When taken together, the available evidence argues that Gram-positive bacteria are important uropathogens in their own right, but that some can be easily overlooked because they are missed by routine diagnostic methods. Finally, a growing body of evidence demonstrates that a surprising variety of fastidious Gram-positive bacteria may either reside in or be regularly exposed to the urinary tract and further suggests that their presence is widespread among women, as well as men. Experimental studies in this area are needed; however, there is a growing appreciation that the composition of bacteria found in the bladder could be a potentially important determinant in urologic disease, including susceptibility to UTI. PMID:27227294

  13. The Pathogenic Potential of Proteus mirabilis Is Enhanced by Other Uropathogens during Polymicrobial Urinary Tract Infection.

    PubMed

    Armbruster, Chelsie E; Smith, Sara N; Johnson, Alexandra O; DeOrnellas, Valerie; Eaton, Kathryn A; Yep, Alejandra; Mody, Lona; Wu, Weisheng; Mobley, Harry L T

    2017-02-01

    Urinary catheter use is prevalent in health care settings, and polymicrobial colonization by urease-positive organisms, such as Proteus mirabilis and Providencia stuartii, commonly occurs with long-term catheterization. We previously demonstrated that coinfection with P. mirabilis and P. stuartii increased overall urease activity in vitro and disease severity in a model of urinary tract infection (UTI). In this study, we expanded these findings to a murine model of catheter-associated UTI (CAUTI), delineated the contribution of enhanced urease activity to coinfection pathogenesis, and screened for enhanced urease activity with other common CAUTI pathogens. In the UTI model, mice coinfected with the two species exhibited higher urine pH values, urolithiasis, bacteremia, and more pronounced tissue damage and inflammation compared to the findings for mice infected with a single species, despite having a similar bacterial burden within the urinary tract. The presence of P. stuartii, regardless of urease production by this organism, was sufficient to enhance P. mirabilis urease activity and increase disease severity, and enhanced urease activity was the predominant factor driving tissue damage and the dissemination of both organisms to the bloodstream during coinfection. These findings were largely recapitulated in the CAUTI model. Other uropathogens also enhanced P. mirabilis urease activity in vitro, including recent clinical isolates of Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, and Pseudomonas aeruginosa We therefore conclude that the underlying mechanism of enhanced urease activity may represent a widespread target for limiting the detrimental consequences of polymicrobial catheter colonization, particularly by P. mirabilis and other urease-positive bacteria.

  14. Impact of Mucorales and Other Invasive Molds on Clinical Outcomes of Polymicrobial Traumatic Wound Infections

    PubMed Central

    Shaikh, Faraz; Weintrob, Amy C.; Rodriguez, Carlos J.; Murray, Clinton K.; Lloyd, Bradley A.; Ganesan, Anuradha; Aggarwal, Deepak; Carson, M. Leigh; Tribble, David R.

    2015-01-01

    Combat trauma wounds with invasive fungal infections (IFIs) are often polymicrobial with fungal and bacterial growth, but the impact of the wound microbiology on clinical outcomes is uncertain. Our objectives were to compare the microbiological features between IFI and non-IFI wounds and evaluate whether clinical outcomes differed among IFI wounds based upon mold type. Data from U.S. military personnel injured in Afghanistan with IFI wounds were examined. Controls were matched by the pattern/severity of injury, including blood transfusion requirements. Wound closure timing was compared between IFI and non-IFI control wounds (with/without bacterial infections). IFI wound closure was also assessed according to mold species isolation. Eighty-two IFI wounds and 136 non-IFI wounds (63 with skin and soft tissue infections [SSTIs] and 73 without) were examined. The time to wound closure was longer for the IFI wounds (median, 16 days) than for the non-IFI controls with/without SSTIs (medians, 12 and 9 days, respectively; P < 0.001). The growth of multidrug-resistant Gram-negative rods was reported among 35% and 41% of the IFI and non-IFI wounds with SSTIs, respectively. Among the IFI wounds, times to wound closure were significantly longer for wounds with Mucorales growth than for wounds with non-Mucorales growth (median, 17 days versus 13 days; P < 0.01). When wounds with Mucorales and Aspergillus spp. growth were compared, there was no significant difference in wound closure timing. Trauma wounds with SSTIs were often polymicrobial, yet the presence of invasive molds (predominant types: order Mucorales, Aspergillus spp., and Fusarium spp.) significantly prolonged the time to wound closure. Overall, the times to wound closure were longest for the IFI wounds with Mucorales growth. PMID:25972413

  15. Individual growth detection of bacterial species in an in vitro oral polymicrobial biofilm model.

    PubMed

    Tabenski, L; Maisch, T; Santarelli, F; Hiller, K-A; Schmalz, G

    2014-11-01

    Most in vitro studies on the antibacterial effects of antiseptics have used planktonic bacteria in monocultures. However, this study design does not reflect the in vivo situation in oral cavities harboring different bacterial species that live in symbiotic relationships in biofilms. The aim of this study was to establish a simple in vitro polymicrobial model consisting of only three bacterial strains of different phases of oral biofilm formation to simulate in vivo oral conditions. Therefore, we studied the biofilm formation of Actinomyces naeslundii (An), Fusobacterium nucleatum (Fn), and Enterococcus faecalis (Ef) on 96-well tissue culture plates under static anaerobic conditions using artificial saliva according to the method established by Pratten et al. that was supplemented with 1 g l(-1) sucrose. Growth was separately determined for each bacterial strain after incubation periods of up to 72 h by means of quantitative real-time polymerase chain reaction and live/dead staining. Presence of an extracellular polymeric substance (EPS) was visualized by Concanavalin A staining. Increasing incubation times of up to 72 h showed adhesion and propagation of the bacterial strains with artificial saliva formulation. An and Ef had significantly higher growth rates than Fn. Live/dead staining showed a median of 49.9 % (range 46.0-53.0 %) of living bacteria after 72 h of incubation, and 3D fluorescence microscopy showed a three-dimensional structure containing EPS. An in vitro oral polymicrobial biofilm model was established to better simulate oral conditions and had the advantage of providing the well-controlled experimental conditions of in vitro testing.

  16. Microbial Protection and Virulence in Periodontal Tissue as a Function of Polymicrobial Communities: Symbiosis and Dysbiosis

    PubMed Central

    Roberts, Frank A.

    2014-01-01

    This review discusses polymicrobial interactions with the host in both health and disease. As our ability improves to identify specific bacterial clonal types both with respect to abundance and location in the oral biofilm we will learn more concerning their contribution to both oral health and disease. Recent studies examining host-bacterial interactions have revealed that commensal bacteria not only protect the host simply by niche occupation, but that bacterial interactions with host tissue can promote the development of proper tissue structure and function. These data indicate that our host-associated polymicrobial communities, such as those found in the oral cavity, co-evolved with us and have become an integral part of who we are. Understanding the microbial community factors that underpin associations with host tissue that contribute to periodontal health may also reveal how dysbiotic periodontopathic oral communities disrupt normal periodontal tissue functions in disease. A disruption of the oral microbial community creates dysbiosis, either by overgrowth of specific or nonspecific microorganisms or changes in the local host response where the community can now support a disease state. Dysbiosis provides the link between systemic changes (e.g., diabetes), exogenous risk factors (e.g., smoking), and the dysbiotic community and can drive the periodontal tissue destruction. Many other risk factors associated with periodontal disease such as stress, aging, and genetics also likely affect the microbial community, and more research is needed utilizing sophisticated bacterial taxonomic techniques to better elucidate these effects on the microbiome and to develop strategies to target the dysbiotic mechanisms and improve periodontal health. PMID:26252399

  17. Microbial protection and virulence in periodontal tissue as a function of polymicrobial communities: symbiosis and dysbiosis.

    PubMed

    Roberts, Frank A; Darveau, Richard P

    2015-10-01

    This review discusses polymicrobial interactions with the host in both health and disease. As our ability to identify specific bacterial clonal types, with respect to their abundance and location in the oral biofilm, improves, we will learn more concerning their contribution to both oral health and disease. Recent studies examining host- bacteria interactions have revealed that commensal bacteria not only protect the host simply by niche occupation, but that bacterial interactions with host tissue can promote the development of proper tissue structure and function. These data indicate that our host-associated polymicrobial communities, such as those found in the oral cavity, co-evolved with us and have become an integral part of who we are. Understanding the microbial community factors that underpin the associations with host tissue that contribute to periodontal health may also reveal how dysbiotic periodontopathic oral communities disrupt normal periodontal tissue functions in disease. A disruption of the oral microbial community creates dysbiosis, either by overgrowth of specific or nonspecific microorganisms or by changes in the local host response where the community can now support a disease state. Dysbiosis provides the link between systemic changes (e.g. diabetes) and exogenous risk factors (e.g. smoking), and the dysbiotic community, and can drive the destruction of periodontal tissue. Many other risk factors associated with periodontal disease, such as stress, aging and genetics, are also likely to affect the microbial community, and more research is needed, utilizing sophisticated bacterial taxonomic techniques, to elucidate these effects on the microbiome and to develop strategies to target the dysbiotic mechanisms and improve periodontal health.

  18. Neonatal endotoxin exposure changes neuroendocrine, cardiovascular function and mortality during polymicrobial sepsis in adult rats.

    PubMed

    Saia, Rafael Simone; Oliveira-Pelegrin, Gabriela Ravanelli; da Silva, Maria Emília Nadaletto Bonifácio; Aguila, Fábio Alves; Antunes-Rodrigues, José; Rocha, Maria José Alves; Cárnio, Evelin Capellari

    2011-08-08

    Our aim was to investigate whether neonatal LPS challenge may improve hormonal, cardiovascular response and mortality, this being a beneficial adaptation when adult rats are submitted to polymicrobial sepsis by cecal ligation and puncture (CLP). Fourteen days after birth, pups received an intraperitoneal injection of lipopolysaccharide (LPS; 100μg/kg) or saline. After 8-12 weeks, they were submitted to CLP, decapitated 4, 6 or 24h after surgery and blood was collected for vasopressin (AVP), corticosterone and nitrate measurement, while AVP contents were measured in neurohypophysis, supra-optic (SON) and paraventricular (PVN) nuclei. Moreover, rats had their mean arterial pressure (MAP) and heart rate (HR) evaluated, and mortality and bacteremia were determined at 24h. Septic animals with neonatal LPS exposure had higher plasma AVP and corticosterone levels, and higher c-Fos expression in SON and PVN at 24h after surgery when compared to saline treated rats. The LPS pretreated group showed increased AVP content in SON and PVN at 6h, while we did not observe any change in neurohypophyseal AVP content. The nitrate levels were significantly reduced in plasma at 6 and 24h after surgery, and in both hypothalamic nuclei only at 6h. Septic animals with neonatal LPS exposure showed increase in MAP during the initial phase of sepsis, but HR was not different from the neonatal saline group. Furthermore, neonatally LPS exposed rats showed a significant decrease in mortality rate as well as in bacteremia. These data suggest that neonatal LPS challenge is able to promote beneficial effects on neuroendocrine and cardiovascular responses to polymicrobial sepsis in adulthood. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Preferential Use of Central Metabolism In Vivo Reveals a Nutritional Basis for Polymicrobial Infection

    PubMed Central

    Alteri, Christopher J.; Himpsl, Stephanie D.; Mobley, Harry L. T.

    2015-01-01

    The human genitourinary tract is a common anatomical niche for polymicrobial infection and a leading site for the development of bacteremia and sepsis. Most uncomplicated, community-acquired urinary tract infections (UTI) are caused by Escherichia coli, while another bacterium, Proteus mirabilis, is more often associated with complicated UTI. Here, we report that uropathogenic E. coli and P. mirabilis have divergent requirements for specific central pathways in vivo despite colonizing and occupying the same host environment. Using mutants of specific central metabolism enzymes, we determined glycolysis mutants lacking pgi, tpiA, pfkA, or pykA all have fitness defects in vivo for P. mirabilis but do not affect colonization of E. coli during UTI. Similarly, the oxidative pentose phosphate pathway is required only for P. mirabilis in vivo. In contrast, gluconeogenesis is required only for E. coli fitness in vivo. The remarkable difference in central pathway utilization between E. coli and P. mirabilis during experimental UTI was also observed for TCA cycle mutants in sdhB, fumC, and frdA. The distinct in vivo requirements between these pathogens suggest E. coli and P. mirabilis are not direct competitors within host urinary tract nutritional niche. In support of this, we found that co-infection with E. coli and P. mirabilis wild-type strains enhanced bacterial colonization and persistence of both pathogens during UTI. Our results reveal that complementary utilization of central carbon metabolism facilitates polymicrobial disease and suggests microbial activity in vivo alters the host urinary tract nutritional niche. PMID:25568946

  20. The Pathogenic Potential of Proteus mirabilis Is Enhanced by Other Uropathogens during Polymicrobial Urinary Tract Infection

    PubMed Central

    Smith, Sara N.; Johnson, Alexandra O.; DeOrnellas, Valerie; Eaton, Kathryn A.; Yep, Alejandra; Mody, Lona; Wu, Weisheng

    2016-01-01

    ABSTRACT Urinary catheter use is prevalent in health care settings, and polymicrobial colonization by urease-positive organisms, such as Proteus mirabilis and Providencia stuartii, commonly occurs with long-term catheterization. We previously demonstrated that coinfection with P. mirabilis and P. stuartii increased overall urease activity in vitro and disease severity in a model of urinary tract infection (UTI). In this study, we expanded these findings to a murine model of catheter-associated UTI (CAUTI), delineated the contribution of enhanced urease activity to coinfection pathogenesis, and screened for enhanced urease activity with other common CAUTI pathogens. In the UTI model, mice coinfected with the two species exhibited higher urine pH values, urolithiasis, bacteremia, and more pronounced tissue damage and inflammation compared to the findings for mice infected with a single species, despite having a similar bacterial burden within the urinary tract. The presence of P. stuartii, regardless of urease production by this organism, was sufficient to enhance P. mirabilis urease activity and increase disease severity, and enhanced urease activity was the predominant factor driving tissue damage and the dissemination of both organisms to the bloodstream during coinfection. These findings were largely recapitulated in the CAUTI model. Other uropathogens also enhanced P. mirabilis urease activity in vitro, including recent clinical isolates of Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, and Pseudomonas aeruginosa. We therefore conclude that the underlying mechanism of enhanced urease activity may represent a widespread target for limiting the detrimental consequences of polymicrobial catheter colonization, particularly by P. mirabilis and other urease-positive bacteria. PMID:27895127

  1. Endocarditis Caused by Culture-Negative Organisms Visible by Brown and Brenn Staining: Utility of PCR and DNA Sequencing for Diagnosis

    PubMed Central

    Wilck, Marissa B.; Wu, Yanyun; Howe, John G.; Crouch, Jill Y.; Edberg, Stephen C.

    2001-01-01

    Two cases of culture-negative endocarditis with cocci seen in valve vegetations are presented. The organisms were identified by molecular analysis using broad-range PCR primers complementary to the 16S rRNA gene, sequencing, and database search using BLAST software. The results and utility of this method are discussed. PMID:11326041

  2. Icodextrin does not impact infectious and culture-negative peritonitis rates in peritoneal dialysis patients: a 2-year multicentre, comparative, prospective cohort study

    PubMed Central

    Vychytil, Andreas; Remón, César; Michel, Catherine; Williams, Paul; Rodríguez-Carmona, Ana; Marrón, Belén; Vonesh, Ed; van der Heyden, Synke; Filho, Jose C. Divino

    2008-01-01

    Background. Icodextrin is a glucose polymer derived by hydrolysis of cornstarch. The different biocompatibility profile of icodextrin-containing peritoneal dialysis (PD) solutions may have a positive influence on peritoneal host defence. Furthermore, cases of sterile peritonitis potentially associated with icodextrin have been reported. Methods. The primary objective of this multicentre, longitudinal, observational, non-interventional, prospective cohort study, which included 722 PD patients, was to evaluate the incidence of overall peritonitis in patients treated with icodextrin-containing PD solutions (Extraneal™) used during one long-dwell exchange/day compared with those treated with non-icodextrin-containing PD solutions. The secondary objective was to determine if culture-negative peritonitis rates differed between patients treated with icodextrin from two independent manufacturers. All peritonitis episodes were assessed by a Steering Committee in a blind manner. Results. There was no significant difference between icodextrin-treated and control patients in the adjusted overall, culture-positive or culture-negative peritonitis rates. When stratified by the icodextrin supplier, there was no significant difference in the adjusted rate of culture-negative peritonitis episodes between groups. Conclusion. Subjects receiving icodextrin as part of their PD regimen experienced neither a higher rate of culture-negative peritonitis nor a lower rate of infectious peritonitis compared with non-icodextrin users. There was no significant influence of the icodextrin raw material supplier on peritonitis rates. PMID:18556747

  3. Icodextrin does not impact infectious and culture-negative peritonitis rates in peritoneal dialysis patients: a 2-year multicentre, comparative, prospective cohort study.

    PubMed

    Vychytil, Andreas; Remón, César; Michel, Catherine; Williams, Paul; Rodríguez-Carmona, Ana; Marrón, Belén; Vonesh, Ed; van der Heyden, Synke; Divino Filho, Jose C

    2008-11-01

    Icodextrin is a glucose polymer derived by hydrolysis of cornstarch. The different biocompatibility profile of icodextrin-containing peritoneal dialysis (PD) solutions may have a positive influence on peritoneal host defence. Furthermore, cases of sterile peritonitis potentially associated with icodextrin have been reported. The primary objective of this multicentre, longitudinal, observational, non-interventional, prospective cohort study, which included 722 PD patients, was to evaluate the incidence of overall peritonitis in patients treated with icodextrin-containing PD solutions (Extraneal) used during one long-dwell exchange/day compared with those treated with non-icodextrin-containing PD solutions. The secondary objective was to determine if culture-negative peritonitis rates differed between patients treated with icodextrin from two independent manufacturers. All peritonitis episodes were assessed by a Steering Committee in a blind manner. There was no significant difference between icodextrin-treated and control patients in the adjusted overall, culture-positive or culture-negative peritonitis rates. When stratified by the icodextrin supplier, there was no significant difference in the adjusted rate of culture-negative peritonitis episodes between groups. Subjects receiving icodextrin as part of their PD regimen experienced neither a higher rate of culture-negative peritonitis nor a lower rate of infectious peritonitis compared with non-icodextrin users. There was no significant influence of the icodextrin raw material supplier on peritonitis rates.

  4. Identification of risk factors for the development of clostridium difficile-associated diarrhea following treatment of polymicrobial surgical infections.

    PubMed

    Metzger, Rosemarie; Swenson, Brian R; Bonatti, Hugo; Hedrick, Traci L; Hranjec, Tjasa; Popovsky, Kimberley A; Pruett, Timothy L; Sawyer, Robert G

    2010-04-01

    To identify risk factors for Clostridium difficile-associated diarrhea (CDAD) in surgical patients following treatment of polymicrobial infections. Infections among surgical patients are frequently anaerobic or mixed aerobic-anaerobic infections and are therefore subject to polymicrobial antibiotic coverage, including metronidazole. While multiple antibiotics are known to contribute to the development of CDAD, the role of preventive antibiotics is unproven. An 11-year dataset of consecutive infections treated in surgical patients at a single hospital was reviewed. All intra-abdominal, surgical site, or skin/skin structure infections were identified. Each infection was evaluated for antibiotic coverage and subsequent CDAD. Antibiotic usage was assessed using chi analysis. A multiple logistic regression was used to identify independent predictors of CDAD. A total of 4178 intra-abdominal, surgical site, or skin/skin structure infections were identified. Of these infections, 98 were followed by CDAD. Only carbapenem use affected the incidence of CDAD: 3.5% of infections treated with a carbapenem were followed by CDAD, whereas only 2.1% of infections treated without carbapenems were followed by CDAD (P = 0.04). Metronidazole had no association with future CDAD. Only age and Acute Physiology and Chronic Health Evaluation II (APACHE II) score were independently associated with CDAD by multiple logistic regression analysis. Older patients with a high severity of illness are at greatest risk for developing CDAD following treatment of polymicrobial infections. No specific antibiotic class, including fluoroquinolones, is associated with an increased incidence of CDAD in this population. Although use of metronidazole in the treatment of polymicrobial infections is appropriate for anaerobic coverage, it does not reduce the risk of future CDAD.

  5. Identification of Risk Factors for the Development of Clostridium difficile-Associated Diarrhea Following Treatment of Polymicrobial Surgical Infections

    PubMed Central

    Metzger, Rosemarie; Swenson, Brian R.; Bonatti, Hugo; Hedrick, Traci L.; Hranjec, Tjasa; Popovsky, Kimberley A.; Pruett, Timothy L.; Sawyer, Robert G.

    2011-01-01

    Objective To identify risk factors for Clostridium difficile-associated diarrhea (CDAD) in surgical patients following treatment of polymicrobial infections. Summary Background Data Infections among surgical patients are frequently anaerobic or mixed aerobic-anaerobic infections and are therefore subject to polymicrobial antibiotic coverage, including metronidazole. While multiple antibiotics are known to contribute to the development of CDAD, the role of preventive antibiotics is unproven. Methods An 11-year dataset of consecutive infections treated in surgical patients at a single hospital was reviewed. All intra-abdominal, surgical site, or skin/skin structure infections were identified. Each infection was evaluated for antibiotic coverage and subsequent CDAD. Antibiotic usage was assessed using χ2 analysis. A multiple logistic regression was used to identify independent predictors of CDAD. Results A total of 4178 intra-abdominal, surgical site, or skin/skin structure infections were identified. Of these infections, 98 were followed by CDAD. Only carbapenem use affected the incidence of CDAD: 3.5% of infections treated with a carbapenem were followed by CDAD, whereas only 2.1% of infections treated without carbapenems were followed by CDAD (P = 0.04). Metronidazole had no association with future CDAD. Only age and Acute Physiology and Chronic Health Evaluation II (APACHE II) score were independently associated with CDAD by multiple logistic regression analysis. Conclusions Older patients with a high severity of illness are at greatest risk for developing CDAD following treatment of polymicrobial infections. No specific antibiotic class, including fluoroquinolones, is associated with an increased incidence of CDAD in this population. Although use of metronidazole in the treatment of polymicrobial infections is appropriate for anaerobic coverage, it does not reduce the risk of future CDAD. PMID:20101175

  6. Nonencapsulated Streptococcus pneumoniae causes otitis media during single-species infection and during polymicrobial infection with nontypeable Haemophilus influenzae.

    PubMed

    Murrah, Kyle A; Pang, Bing; Richardson, Stephen; Perez, Antonia; Reimche, Jennifer; King, Lauren; Wren, John; Swords, W Edward

    2015-07-01

    Streptococcus pneumoniae strains lacking capsular polysaccharide have been increasingly reported in carriage and disease contexts. Since most cases of otitis media involve more than one bacterial species, we aimed to determine the capacity of a nonencapsulated S. pneumoniae clinical isolate to induce disease in the context of a single-species infection and as a polymicrobial infection with nontypeable Haemophilus influenzae. Using the chinchilla model of otitis media, we found that nonencapsulated S. pneumoniae colonizes the nasopharynx following intranasal inoculation, but does not readily ascend into the middle ear. However, when we inoculated nonencapsulated S. pneumoniae directly into the middle ear, the bacteria persisted for two weeks post-inoculation and induced symptoms consistent with chronic otitis media. During coinfection with nontypeable H. influenzae, both species persisted for one week and induced polymicrobial otitis media. We also observed that nontypeable H. influenzae conferred passive protection from killing by amoxicillin upon S. pneumoniae from within polymicrobial biofilms in vitro. Therefore, based on these results, we conclude that nonencapsulated pneumococci are a potential causative agent of chronic/recurrent otitis media, and can also cause mutualistic infection with other opportunists, which could complicate treatment outcomes.

  7. Nonencapsulated Streptococcus pneumoniae causes otitis media during single-species infection and during polymicrobial infection with nontypeable Haemophilus influenzae

    PubMed Central

    Murrah, Kyle A.; Pang, Bing; Richardson, Stephen; Perez, Antonia; Reimche, Jennifer; King, Lauren; Wren, John; Swords, W. Edward

    2014-01-01

    Streptococcus pneumoniae strains lacking capsular polysaccharide have been increasingly reported in carriage and disease contexts. Since most cases of otitis media involve more than one bacterial species, we aimed to determine the capacity of a nonencapsulated S. pneumoniae clinical isolate to induce disease in the context of a single-species infection and as a polymicrobial infection with nontypeable Haemophilus influenzae. Using the chinchilla model of otitis media, we found that nonencapsulated S. pneumoniae colonizes the nasopharynx following intranasal inoculation, but does not readily ascend into the middle ear. However, when we inoculated nonencapsulated S. pneumoniae directly into the middle ear, the bacteria persisted for two weeks post-inoculation and induced symptoms consistent with chronic otitis media. During coinfection with nontypeable H. influenzae, both species persisted for one week and induced polymicrobial otitis media. We also observed that nontypeable H. influenzae conferred passive protection from killing by amoxicillin upon S. pneumoniae from within polymicrobial biofilms in vitro. Therefore, based on these results, we conclude that nonencapsulated pneumococci are a potential causative agent of chronic/recurrent otitis media, and can also cause mutualistic infection with other opportunists, which could complicate treatment outcomes. PMID:26014114

  8. PPAR-γ/IL-10 axis inhibits MyD88 expression and ameliorates murine polymicrobial sepsis.

    PubMed

    Ferreira, Ana Elisa; Sisti, Flavia; Sônego, Fabiane; Wang, Suojuan; Filgueiras, Luciano Ribeiro; Brandt, Stephanie; Serezani, Ana Paula Moreira; Du, Hong; Cunha, Fernando Q; Alves-Filho, Jose Carlos; Serezani, Carlos Henrique

    2014-03-01

    Polymicrobial sepsis induces organ failure and is accompanied by overwhelming inflammatory response and impairment of microbial killing. Peroxisome proliferator-activated receptor (PPAR)-γ is a nuclear receptor with pleiotropic effects on lipid metabolism, inflammation, and cell proliferation. The insulin-sensitizing drugs thiazolidinediones (TZDs) are specific PPAR-γ agonists. TZDs exert anti-inflammatory actions in different disease models, including polymicrobial sepsis. The TZD pioglitazone, which has been approved by the U.S. Food and Drug Administration, improves sepsis outcome; however, the molecular programs that mediate its effect have not been determined. In a murine model of sepsis, we now show that pioglitazone treatment improves microbial clearance and enhances neutrophil recruitment to the site of infection. We also observed reduced proinflammatory cytokine production and high IL-10 levels in pioglitazone-treated mice. These effects were associated with a decrease in STAT-1-dependent expression of MyD88 in vivo and in vitro. IL-10R blockage abolished PPAR-γ-mediated inhibition of MyD88 expression. These data demonstrate that the primary mechanism by which pioglitazone protects against polymicrobial sepsis is through the impairment of MyD88 responses. This appears to represent a novel regulatory program. In this regard, pioglitazone provides advantages as a therapeutic tool, because it improves different aspects of host defense during sepsis, ultimately enhancing survival.

  9. Antimicrobial-bonded graft patency in the setting of a polymicrobial infection in swine (Sus scrofa).

    PubMed

    Clemens, Michael S; Stull, Mamie C; Hata, Kai W; Heafner, Thomas A; Watson, J Devin B; Arthurs, Zachary M; Propper, Brandon W

    2017-10-01

    Polytetrafluoroethylene (PTFE) and Dacron are commonly used as arterial conduits in vascular trauma or infection when vein interposition graft may not be available. This study used a previously validated large animal model of polymicrobial infection to assess the patency and infectious resistance of a novel, antibiotic-impregnated graft material compared with PTFE and Dacron. Forty-eight animals were placed into five groups for a 21-day survival period. A 6-mm PTFE, Dacron, or antimicrobial-bonded graft was used to replace the iliac artery and then inoculated with 1 × 10(7) colonies/mL of genetically labeled Pseudomonas aeruginosa and Staphylococcus aureus. Native vessels with and without contamination served as control groups. The primary end points were graft patency (determined by duplex ultrasound and necropsy) and graft infection (culture with molecular analysis). Secondary end points included physiologic measurements, blood cultures, laboratory data, and histopathology. At 21 days, 50% of PTFE, 62.5% of Dacron, and 100% of the antimicrobial-bonded grafts remained patent (P = .04). PTFE and Dacron had an equivalent number of overall infections, 87.5% and 75%, respectively (P = 1.0). There was no significant difference of infectious organisms between standard materials. The infection rate of the antimicrobial-bonded graft (25%) was significantly less than that of both PTFE and Dacron (P < .01), and all of these infections were secondary to P. aeruginosa. Clinical data did not vary significantly between groups. There were no mortalities in the protocol secondary to graft blowout or sepsis. The antimicrobial-bonded graft material outperformed standard PTFE and Dacron in the setting of polymicrobial infection with regard to graft patency and infection. The novel prosthetic material appears to be resistant to infection with S. aureus and to limit the growth of P. aeruginosa. Additional studies are recommended to explore the role of this antibiotic

  10. Melatonin receptors mediate improvements of survival in a model of polymicrobial sepsis.

    PubMed

    Fink, Tobias; Glas, Michael; Wolf, Alexander; Kleber, Astrid; Reus, Erik; Wolff, Martin; Kiefer, Daniel; Wolf, Beate; Rensing, Hauke; Volk, Thomas; Mathes, Alexander M

    2014-01-01

    Melatonin has been demonstrated to improve survival after experimental sepsis via antioxidant effects. Yet, recent evidence suggests that this protective capacity may also rely on melatonin receptor activation. Therefore, the present study was designed to investigate whether selective melatonin receptor-agonist ramelteon may influence survival and immune response in a model of polymicrobial sepsis in rats, wild-type and melatonin receptor MT1/MT2 double knockout mice. Prospective, randomized, controlled study. University research laboratory. Male Sprague-Dawley rats (200-250 g) and male C3H/HeN wild-type and MT1/MT2 receptor knockout mice (20-22 g). Animals underwent cecal ligation and incision and remained anesthetized for evaluation of survival for 12 hours (rats: n = 15 per group) or 15 hours (mice: n = 10 per group). Analysis of immune response by means of enzyme-linked immunosorbent assay was performed before and 5 hours after cecal ligation and incision (rats only; n = 5 per group). After induction of sepsis, animals were treated IV with vehicle, different doses of melatonin (rats: 0.01/0.1/1.0/10 mg/kg; mice: 1.0 mg/kg), ramelteon, melatonin receptor-antagonist luzindole, ramelteon + luzindole, or melatonin + luzindole (each 1.0 mg/kg). Sham controls underwent laparotomy but not cecal ligation and incision. Compared with vehicle, administration of ramelteon or melatonin significantly improved median survival time in rats (sepsis/melatonin [0.1 mg/kg], 554 min, [1.0 mg/kg] 570 min, [10 mg/kg] 579 min; sepsis/ramelteon, 468 min; each p < 0.001 vs sepsis/vehicle, 303 min) and wild-type mice (sepsis/melatonin, 781 min; sepsis/ramelteon, 701 min; both p < 0.001 vs sepsis/vehicle, 435 min). This effect was completely antagonized by coadministration of luzindole in all groups. Melatonin, ramelteon, or luzindole had no significant effect on survival time in knockout mice. Significantly elevated concentrations of tumor necrosis factor

  11. Polymicrobial nature of chronic diabetic foot ulcer biofilm infections determined using bacterial tag encoded FLX amplicon pyrosequencing (bTEFAP).

    PubMed

    Dowd, Scot E; Wolcott, Randall D; Sun, Yan; McKeehan, Trevor; Smith, Ethan; Rhoads, Daniel

    2008-10-03

    Diabetic extremity ulcers are associated with chronic infections. Such ulcer infections are too often followed by amputation because there is little or no understanding of the ecology of such infections or how to control or eliminate this type of chronic infection. A primary impediment to the healing of chronic wounds is biofilm phenotype infections. Diabetic foot ulcers are the most common, disabling, and costly complications of diabetes. Here we seek to derive a better understanding of the polymicrobial nature of chronic diabetic extremity ulcer infections. Using a new bacterial tag encoded FLX amplicon pyrosequencing (bTEFAP) approach we have evaluated the bacterial diversity of 40 chronic diabetic foot ulcers from different patients. The most prevalent bacterial genus associated with diabetic chronic wounds was Corynebacterium spp. Findings also show that obligate anaerobes including Bacteroides, Peptoniphilus, Fingoldia, Anaerococcus, and Peptostreptococcus spp. are ubiquitous in diabetic ulcers, comprising a significant portion of the wound biofilm communities. Other major components of the bacterial communities included commonly cultured genera such as Streptococcus, Serratia, Staphylococcus and Enterococcus spp. In this article, we highlight the patterns of population diversity observed in the samples and introduce preliminary evidence to support the concept of functional equivalent pathogroups (FEP). Here we introduce FEP as consortia of genotypically distinct bacteria that symbiotically produce a pathogenic community. According to this hypothesis, individual members of these communities when they occur alone may not cause disease but when they coaggregate or consort together into a FEP the synergistic effect provides the functional equivalence of well-known pathogens, such as Staphylococcus aureus, giving the biofilm community the factors necessary to maintain chronic biofilm infections. Further work is definitely warranted and needed in order to prove

  12. Blockade of the JNK Signalling as a Rational Therapeutic Approach to Modulate the Early and Late Steps of the Inflammatory Cascade in Polymicrobial Sepsis

    PubMed Central

    Interdonato, Monica; Mecchio, Anna; De Luca, Filippo; Minutoli, Letteria; Squadrito, Francesco

    2015-01-01

    Cecal ligation and puncture (CLP) is an experimental polymicrobial sepsis induced systemic inflammation that leads to acute organ failure. Aim of our study was to evaluate the effects of SP600125, a specific c-Jun NH2-terminal kinase (JNK) inhibitor, to modulate the early and late steps of the inflammatory cascade in a murine model of CLP-induced sepsis. CB57BL/6J mice were subjected to CLP or sham operation. Animals were randomized to receive either SP600125 (15 mg/kg) or its vehicle intraperitoneally 1 hour after surgery and repeat treatment every 24 hours. To evaluate survival, a group of animals was monitored every 24 hours for 120 hours. Two other animals were sacrificed 4 or 18 hours after surgical procedures; lung and liver samples were collected for biomolecular and histopathologic analysis. The expression of p-JNK, p-ERK, TNF-α, HMGB-1, NF-κB, Ras, Rho, Caspase 3, Bcl-2, and Bax was evaluated in lung and liver samples; SP600125 improved survival, reduced CLP induced activation of JNK, NF-κB, TNF-α, and HMGB-1, inhibited proapoptotic pathway, preserved Bcl-2 expression, and reduced histologic damage in both lung and liver of septic mice. SP600125 protects against CLP induced sepsis by blocking JNK signalling; therefore, it can be considered a therapeutic approach in human sepsis. PMID:25873765

  13. Aerococcus christensenii as Part of Severe Polymicrobial Chorioamnionitis in a Pregnant Woman

    PubMed Central

    Carlstein, Catrine; Marie Søes, Lillian; Jørgen Christensen, Jens

    2016-01-01

    Chorioamnionitis is a potentially life threatening infection of the fetal membranes, commonly caused by ascending bacteria from the vagina and cervix. In our case, a healthy nullipara with a term pregnancy presented clinical signs of infection after induced labour with an intracervical balloon. Thick green and foul smelling amniotic fluid was observed and culture showed massive growth of Aerococcus christensenii, a facultative anaerob species found in the human vagina, previously only rarely alleged to cause invasive infection. Additional testing with 16S rRNA gene analysis also identified the presence of Gemella asaccharolytica, Snethia sanguinegens, Parvimonas micra and Streptobacillus moniliformis. The patient was treated with cefuroxime and metronidazole and recovered quickly. The newborn showed no signs of infection. This case points at the possible role of these pathogens in female genital tract infections. The case also underlines the importance of the combination of culture and culture independent diagnostic approaches to reveal possible polymicrobial natures of selected infections, in this case chorioamnionitis. PMID:27014376

  14. Host-to-host variation of ecological interactions in polymicrobial infections

    PubMed Central

    Mukherjee, Sayak; Weimer, Kristin E.; Seok, Sang-Cheol; Ray, Will C.; Jayaprakash, C.; Vieland, Veronica J.; Swords, W. Edward

    2014-01-01

    Host-to-host variability with respect to interactions between microorganisms and multicellular hosts are commonly observed in infection and in homeostasis. However, the majority of mechanistic models used to analyze host-microorganism relationships, as well as most of the ecological theories proposed to explain coevolution of hosts and microbes, are based on averages across a host population. By assuming that observed variations are random and independent, these models overlook the role of differences between hosts. Here, we analyze mechanisms underlying host-to-host variations of bacterial infection kinetics, using the well characterized experimental infection model of polymicrobial otitis media (OM) in chinchillas, in combination with population dynamic models and a Maximum Entropy (MaxEnt) based inference scheme. We find that the nature of the interactions between bacterial species critically regulates host-to-host variations in these interactions. Surprisingly, seemingly unrelated phenomena, such as the efficiency of individual bacterial species in utilizing nutrients for growth, and the microbe-specific host immune response, can become interdependent in a host population. The latter finding suggests a potential mechanism that could lead to selection of specific strains of bacterial species during the coevolution of the host immune response and the bacterial species. PMID:25473880

  15. PAD4-deficiency does not affect bacteremia in polymicrobial sepsis and ameliorates endotoxemic shock

    PubMed Central

    Martinod, Kimberly; Fuchs, Tobias A.; Zitomersky, Naamah L.; Wong, Siu Ling; Demers, Melanie; Gallant, Maureen; Wang, Yanming

    2015-01-01

    Neutrophil extracellular traps (NETs), consisting of nuclear DNA with histones and microbicidal proteins, are expelled from activated neutrophils during sepsis. NETs were shown to trap microbes, but they also fuel cardiovascular, thrombotic, and autoimmune disease. The role of NETs in sepsis, particularly the balance between their antimicrobial and cytotoxic actions, remains unclear. Neutrophils from peptidylarginine deiminase 4-(PAD4−/−) deficient mice, which lack the enzyme allowing for chromatin decondensation and NET formation, were evaluated. We found that neutrophil functions involved in bacterial killing, other than NETosis, remained intact. Therefore, we hypothesized that prevention of NET formation might not have devastating consequences in sepsis. To test this, we subjected the PAD4−/− mice to mild and severe polymicrobial sepsis produced by cecal ligation and puncture. Surprisingly, under septic conditions, PAD4−/− mice did not fare worse than wild-type mice and had comparable survival. In the presence of antibiotics, PAD4-deficiency resulted in slightly accelerated mortality but bacteremia was unaffected. PAD4−/− mice were partially protected from lipopolysaccharide-induced shock, suggesting that PAD4/NETs may contribute to the toxic inflammatory and procoagulant host response to endotoxin. We propose that preventing NET formation by PAD4 inhibition in inflammatory or thrombotic diseases is not likely to increase host vulnerability to bacterial infections. PMID:25624317

  16. Characterization of the systemic loss of dendritic cells in murine lymph nodes during polymicrobial sepsis.

    PubMed

    Efron, Philip A; Martins, Antonio; Minnich, Douglas; Tinsley, Kevin; Ungaro, Ricardo; Bahjat, Frances R; Hotchkiss, Richard; Clare-Salzler, Michael; Moldawer, Lyle L

    2004-09-01

    Dendritic cells (DCs) play a key role in critical illness and are depleted in spleens from septic patients and mice. To date, few studies have characterized the systemic effect of sepsis on DC populations in lymphoid tissues. We analyzed the phenotype of DCs and Th cells present in the local (mesenteric) and distant (inguinal and popliteal) lymph nodes of mice with induced polymicrobial sepsis (cecal ligation and puncture). Flow cytometry and immunohistochemical staining demonstrated that there was a significant local (mesenteric nodes) and partial systemic (inguinal, but not popliteal nodes) loss of DCs from lymph nodes in septic mice, and that this process was associated with increased apoptosis. This sepsis-induced loss of DCs occurred after CD3(+)CD4(+) T cell activation and loss in the lymph nodes, and the loss of DCs was not preceded by any sustained increase in their maturation status. In addition, there was no preferential loss of either mature/activated (MHCII(high)/CD86(high)) or immature (MHCII(low)/CD86(low)) DCs during sepsis. However, there was a preferential loss of CD8(+) DCs in the local and distant lymph nodes. The loss of DCs in lymphoid tissue, particularly CD8(+) lymphoid-derived DCs, may contribute to the alterations in acquired immune status that frequently accompany sepsis.

  17. Aerococcus christensenii as Part of Severe Polymicrobial Chorioamnionitis in a Pregnant Woman.

    PubMed

    Carlstein, Catrine; Marie Søes, Lillian; Jørgen Christensen, Jens

    2016-01-01

    Chorioamnionitis is a potentially life threatening infection of the fetal membranes, commonly caused by ascending bacteria from the vagina and cervix. In our case, a healthy nullipara with a term pregnancy presented clinical signs of infection after induced labour with an intracervical balloon. Thick green and foul smelling amniotic fluid was observed and culture showed massive growth of Aerococcus christensenii, a facultative anaerob species found in the human vagina, previously only rarely alleged to cause invasive infection. Additional testing with 16S rRNA gene analysis also identified the presence of Gemella asaccharolytica, Snethia sanguinegens, P arvimonas micra and S treptobacillus moniliformis. The patient was treated with cefuroxime and metronidazole and recovered quickly. The newborn showed no signs of infection. This case points at the possible role of these pathogens in female genital tract infections. The case also underlines the importance of the combination of culture and culture independent diagnostic approaches to reveal possible polymicrobial natures of selected infections, in this case chorioamnionitis.

  18. Mincle activation enhances neutrophil migration and resistance to polymicrobial septic peritonitis

    PubMed Central

    Lee, Wook-Bin; Yan, Ji-Jing; Kang, Ji-Seon; Zhang, Quanri; Choi, Won Young; Kim, Lark Kyun; Kim, Young-Joon

    2017-01-01

    Sepsis is a systemic inflammatory response to bacterial infection. The therapeutic options for treating sepsis are limited. Impaired neutrophil recruitment into the infection site is directly associated with severe sepsis, but the precise mechanism is unclear. Here, we show that Mincle plays a key role in neutrophil migration and resistance during polymicrobial sepsis. Mincle-deficient mice exhibited lower survival rates in experimental sepsis from cecal ligation and puncture and Escherichia coli–induced peritonitis. Mincle deficiency led to higher serum inflammatory cytokine levels and reduced bacterial clearance and neutrophil recruitment. Transcriptome analyses revealed that trehalose dimycolate, a Mincle ligand, reduced the expression of G protein–coupled receptor kinase 2 (GRK2) in neutrophils. Indeed, GRK2 expression was upregulated, but surface expression of the chemokine receptor CXCR2 was downregulated in blood neutrophils from Mincle-deficient mice with septic injury. Moreover, CXCL2-mediated adhesion, chemotactic responses, and F-actin polymerization were reduced in Mincle-deficient neutrophils. Finally, we found that fewer Mincle-deficient neutrophils infiltrated from the blood circulation into the peritoneal fluid in bacterial septic peritonitis compared with wild-type cells. Thus, our results indicate that Mincle plays an important role in neutrophil infiltration and suggest that Mincle signaling may provide a therapeutic target for treating sepsis. PMID:28112221

  19. CXCL1 contributes to host defense in polymicrobial sepsis via modulating T cell and neutrophil functions.

    PubMed

    Jin, Liliang; Batra, Sanjay; Douda, David Nobuhiro; Palaniyar, Nades; Jeyaseelan, Samithamby

    2014-10-01

    Severe bacterial sepsis leads to a proinflammatory condition that can manifest as septic shock, multiple organ failure, and death. Neutrophils are critical for the rapid elimination of bacteria; however, the role of neutrophil chemoattractant CXCL1 in bacterial clearance during sepsis remains elusive. To test the hypothesis that CXCL1 is critical to host defense during sepsis, we used CXCL1-deficient mice and bone marrow chimeras to demonstrate the importance of this molecule in sepsis. We demonstrate that CXCL1 plays a pivotal role in mediating host defense to polymicrobial sepsis after cecal ligation and puncture in gene-deficient mice. CXCL1 appears to be essential for restricting bacterial outgrowth and death in mice. CXCL1 derived from both hematopoietic and resident cells contributed to bacterial clearance. Moreover, CXCL1 is essential for neutrophil migration, expression of proinflammatory mediators, activation of NF-κB and MAPKs, and upregulation of adhesion molecule ICAM-1. rIL-17 rescued impaired host defenses in cxcl1(-/-) mice. CXCL1 is important for IL-17A production via Th17 differentiation. CXCL1 is essential for NADPH oxidase-mediated reactive oxygen species production and neutrophil extracellular trap formation. This study reveals a novel role for CXCL1 in neutrophil recruitment via modulating T cell function and neutrophil-related bactericidal functions. These studies suggest that modulation of CXCL1 levels in tissues and blood could reduce bacterial burden in sepsis.

  20. PAD4-deficiency does not affect bacteremia in polymicrobial sepsis and ameliorates endotoxemic shock.

    PubMed

    Martinod, Kimberly; Fuchs, Tobias A; Zitomersky, Naamah L; Wong, Siu Ling; Demers, Melanie; Gallant, Maureen; Wang, Yanming; Wagner, Denisa D

    2015-03-19

    Neutrophil extracellular traps (NETs), consisting of nuclear DNA with histones and microbicidal proteins, are expelled from activated neutrophils during sepsis. NETs were shown to trap microbes, but they also fuel cardiovascular, thrombotic, and autoimmune disease. The role of NETs in sepsis, particularly the balance between their antimicrobial and cytotoxic actions, remains unclear. Neutrophils from peptidylarginine deiminase 4-(PAD4(-/-)) deficient mice, which lack the enzyme allowing for chromatin decondensation and NET formation, were evaluated. We found that neutrophil functions involved in bacterial killing, other than NETosis, remained intact. Therefore, we hypothesized that prevention of NET formation might not have devastating consequences in sepsis. To test this, we subjected the PAD4(-/-) mice to mild and severe polymicrobial sepsis produced by cecal ligation and puncture. Surprisingly, under septic conditions, PAD4(-/-) mice did not fare worse than wild-type mice and had comparable survival. In the presence of antibiotics, PAD4-deficiency resulted in slightly accelerated mortality but bacteremia was unaffected. PAD4(-/-) mice were partially protected from lipopolysaccharide-induced shock, suggesting that PAD4/NETs may contribute to the toxic inflammatory and procoagulant host response to endotoxin. We propose that preventing NET formation by PAD4 inhibition in inflammatory or thrombotic diseases is not likely to increase host vulnerability to bacterial infections.

  1. Polymicrobial sepsis alters Ag-dependent and -independent memory CD8 T cell functions1

    PubMed Central

    Duong, Sean; Condotta, Stephanie A.; Rai, Deepa; Martin, Matthew D.; Griffith, Thomas S.; Badovinac, Vladimir P.

    2014-01-01

    Mortality from sepsis frequently results from secondary infections, and the extent to which sepsis affects pathogen-specific memory CD8 T cell responses remains unknown. Using the cecal-ligation and puncture (CLP) model of polymicrobial sepsis, we observed rapid apoptosis of pre-existing memory CD8 T cells after sepsis induction that led to a loss in CD8 T cell-mediated protection. Ag-sensitivity (functional avidity) and Ag-driven secondary expansion of memory CD8 T cells were decreased after sepsis, further contributing to the observed loss in CD8 T cell-mediated immunity. Moreover, Ag-independent bystander activation of memory CD8 T cells in response to heterologous infection was also significantly impaired early after sepsis induction. The reduced sensitivity of pre-existing memory CD8 T cells to sense inflammation and respond to heterologous infection by IFN-γ production was observed in inbred and outbred hosts and controlled by extrinsic (but not cell intrinsic) factors suggesting that sepsis-induced changes in the environment regulates innate functions of memory CD8 T cells. Taken together, the data in this study revealed a previously unappreciated role of sepsis in shaping the quantity and functionality of infection- or vaccine-induced memory CD8 T cells and will help further define the decline in T cell-mediated immunity during the sepsis-induced phase of immunosuppression. PMID:24646738

  2. Polymicrobial infection alter inflammatory microRNA in rat salivary glands during periodontal disease.

    PubMed

    Nayar, Gautam; Gauna, Adrienne; Chukkapalli, Sasanka; Velsko, Irina; Kesavalu, Lakshmyya; Cha, Seunghee

    2016-04-01

    Periodontal disease initiated by subgingival pathogens is linked with diminished secretion of saliva, and implies pathogenic bacteria dissemination to or affects secondary sites such as the salivary glands. MicroRNAs activated in response to bacteria may modulate immune responses against pathogens. Therefore, Sprague-Dawley rats were infected by oral lavage consisting of polymicrobial inocula, namely Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, or sham-infected for 12 weeks (n = 6). We quantified inflammatory miRNA expression levels of miRNA-132, miR-146a, and miR-155 at secondary sites to the primary infection of the gingiva, including submandibular salivary glands, lacrimal glands, and pancreas. The presence of bacteria was detected in situ at secondary sites. Infected rat gingiva showed increased relative expression of miR-155. In contrast, miRNA-155 expression was decreased in submandibular salivary glands, along with positive identification of P. gingivalis in 2/6 and T. denticola in 1/6 rat salivary glands. Furthermore, miRNA-132 and miRNA-146a were significantly decreased in the pancreas of infected rats. This study is the first to show primary periodontal infections can alter miRNA profiles in secondary sites such as the salivary gland and pancreas. Whether these alterations contribute to pathologies of salivary glands in Sjögren's syndrome or of pancreas in diabetes warrants further investigation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Resistance to disinfection of a polymicrobial association contaminating the surface of elastomeric dental impressions.

    PubMed

    Giammanco, Giovanni M; Melilli, Dario; Rallo, Antonio; Pecorella, Sonia; Mammina, Caterina; Pizzo, Giuseppe

    2009-04-01

    The aim of this study was to evaluate the ability to resist disinfection of a polymicrobial association contaminating the surface of dental impressions obtained with two different elastomers: a polyether (Impregum) and an addition-polymerized silicone (Elite). Impressions were contaminated with a mixture of three biofilm-forming microorganisms (Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans) and disinfected immediately after contamination, or after microbial layers were allowed to develop during a six-hour storage. Two commercial disinfectants were tested: MD 520 containing 0.5% glutaraldehyde and Sterigum Powder without glutaraldehyde. Residual contamination was recovered by mechanical rinsing immediately after disinfection and after a six-hour storage of disinfected impressions, and assessed by colony counting. Both disinfectants tested were shown to be effective in reducing the microbial presence on the impression materials, achieving at least a 102 reduction of microbial counts compared to water rinsing. However, Sterigum was generally less effective on the Elite elastomer and could not grant disinfection on six-hour aged P. aeruginosa and C. albicans microbial layers. The results of this study suggest that the materials used for the impressions influence the efficacy of disinfection. Disinfectants should be tested according to conditions encountered in everyday clinical practice and the need for immediate disinfection of impressions should be clearly indicated by manufacturers.

  4. Host-to-host variation of ecological interactions in polymicrobial infections

    NASA Astrophysics Data System (ADS)

    Mukherjee, Sayak; Weimer, Kristin E.; Seok, Sang-Cheol; Ray, Will C.; Jayaprakash, C.; Vieland, Veronica J.; Swords, W. Edward; Das, Jayajit

    2015-02-01

    Host-to-host variability with respect to interactions between microorganisms and multicellular hosts are commonly observed in infection and in homeostasis. However, the majority of mechanistic models used to analyze host-microorganism relationships, as well as most of the ecological theories proposed to explain coevolution of hosts and microbes, are based on averages across a host population. By assuming that observed variations are random and independent, these models overlook the role of differences between hosts. Here, we analyze mechanisms underlying host-to-host variations of bacterial infection kinetics, using the well characterized experimental infection model of polymicrobial otitis media (OM) in chinchillas, in combination with population dynamic models and a maximum entropy (MaxEnt) based inference scheme. We find that the nature of the interactions between bacterial species critically regulates host-to-host variations in these interactions. Surprisingly, seemingly unrelated phenomena, such as the efficiency of individual bacterial species in utilizing nutrients for growth, and the microbe-specific host immune response, can become interdependent in a host population. The latter finding suggests a potential mechanism that could lead to selection of specific strains of bacterial species during the coevolution of the host immune response and the bacterial species.

  5. Tolerability and efficacy of long-term treatment with daptomycin, ceftazidime and colistin in a patient with a polymicrobial, multidrug-resistant prosthetic joint reinfection: a case report

    PubMed Central

    2014-01-01

    Introduction Prosthetic joint infections are severe complications of joint implants. Further complications arise when polymicrobial and/or multidrug-resistant microorganisms are involved. Currently, there are limited data on the management of these infections and on the tolerability of long-term treatment with daptomycin, ceftazidime and colistin. Case presentation A 55-year-old Caucasian woman who had a right hip prosthesis removed 1 year prior because of infection was admitted for prosthesis reimplantation. On admission at our hospital, anamnesis regarding etiology and management of prosthesis infection was not available. On clinical, laboratory findings and imaging studies infection was not suspected. A hip prosthesis was reimplanted. At surgery, histopathological and microbiological investigations were not taken. Three weeks after reimplantation, surgical site infection due to Enterobacter cloacae was diagnosed and oral ciprofloxacin was prescribed. Four days later, a periprosthesis fluid collection was evidenced and a percutaneous needle aspirate grew Staphylococcus epidermidis and S. haemolyticus. Enterobacter genome was also detected from the same sample. Teicoplanin and meropenem were added to ciprofloxacin without clinical improvement. Moreover, acetabular cup dislocation was documented. She underwent prosthesis explantation, debridement, and positioning of an antimicrobial mixed spacer. From the intraoperatory cultures S. epidermidis and Acinetobacter baumannii were grown. Daptomycin, ceftazidime, colistin and rifampin were administered. Four days later, rifampin was stopped due to a suspected liver toxicity. While undergoing therapy she presented recurrent episodes of wound dehiscence and on the 22nd week of treatment a further surgical debridement was performed, upon which the spacer was removed. At this time, intraoperative cultures resulted negative. Three months later, after a total of 8 months, antimicrobials were interrupted. Subsequently, a

  6. Interferon-gamma assay in combination with tuberculin skin test are insufficient for the diagnosis of culture-negative pulmonary tuberculosis.

    PubMed

    Wlodarczyk, Marcin; Rudnicka, Wieslawa; Janiszewska-Drobinska, Beata; Kielnierowski, Grzegorz; Kowalewicz-Kulbat, Magdalena; Fol, Marek; Druszczynska, Magdalena

    2014-01-01

    Early diagnosis of infectious cases and treatment of tuberculosis (TB) are important strategies for reducing the incidence of this disease. Unfortunately, traditional TB diagnostic methods are time-consuming and often unreliable. This study compared the accuracy and reliability of the tuberculin skin test (TST) and interferon (IFN)-γ-based assay (IGRA) for the diagnosis of active pulmonary TB Polish cases that could or could not be confirmed by M. tuberculosis (M.tb) culture. In total, 126 adult patients with clinically active TB or non-mycobacterial, community-acquired lung diseases (NMLD) hospitalised at the Regional Specialised Hospital of Tuberculosis, Lung Diseases and Rehabilitation in Tuszyn, Poland were enrolled in the present study. Sensitivity, specificity, positive predicted value (PPV), negative predicted value (NPV), and analytic accuracy (Acc) of TST and IGRA testing for the diagnosis of culture-positive and culture-negative TB patients were calculated. The quantities of IFN-γ produced in the response to M.tb specific antigens (TB Ag - Nil) in the cultures of blood from patients with active TB and NMLD patients were also analysed. The IGRA sensitivity in culture-positive and culture-negative TB patients was similar, measuring 65.1% and 55.6%, respectively. The sensitivity of TST did not differ from the parameters designated for IGRA, measuring 55.8% in culture-positive and 64.9% in culture-negative TB. The sensitivity of TST and IGRA was age-dependent and decreased significantly with the age of the patients. No differences in the frequency or intensity of M.tb-stimulated IFN-γ production, as assessed by IGRA testing between culture-positive and culture-negative TB were noticed. Significantly lower concentrations of IFN-γ were observed in patients with advanced TB forms compared with those with mild or moderate TB pathologies. Our results do not show that a combination of IGRA and TST might be a step forward in the diagnosis of culture-negative TB

  7. Bioluminescence based biosensors for quantitative detection of enterococcal peptide-pheromone activity reveal inter-strain telesensing in vivo during polymicrobial systemic infection.

    PubMed

    La Rosa, Sabina Leanti; Solheim, Margrete; Diep, Dzung B; Nes, Ingolf F; Brede, Dag Anders

    2015-02-09

    Enterococcus faecalis is a significant threat in the nosocomial setting due to the emergence of isolates that are multi-antibiotic resistant, refractory to the available therapies and equipped with a variety of pathogenicity determinants. This bacterium uses quorum-sensing systems to regulate its physiological processes, including the expression of virulence traits, to adapt and proliferate within a host. Here, we describe the construction and application of two bioluminescence-based reporter systems for the direct detection of the quorum-sensing regulated expression of (i) the gelatinase biosynthesis-activating pheromone (GBAP) and (ii) the cytolysin small subunit (CylL(S)) in natural samples. The two E. faecalis reporters conditionally expressed bioluminescence in the presence of GBAP and CylL(S) both in the supernatants of liquid cultures and in an agar-overlay assay in as little as three hours, with a high level of sensitivity. Biosensors employed to investigate the interaction between the fsr and cyl systems revealed that fsr impeded CylL(S) activity by 75%. Furthermore, we identified a clinical E. faecalis isolate that acted as a biological cheater, producing cytolysin only upon sensing CylL(S)-producers in its environment. This isolate enhanced its virulence during polymicrobial systemic infection of Galleria mellonella.

  8. Bioluminescence based biosensors for quantitative detection of enterococcal peptide–pheromone activity reveal inter-strain telesensing in vivo during polymicrobial systemic infection

    PubMed Central

    La Rosa, Sabina Leanti; Solheim, Margrete; Diep, Dzung B.; Nes, Ingolf F.; Brede, Dag Anders

    2015-01-01

    Enterococcus faecalis is a significant threat in the nosocomial setting due to the emergence of isolates that are multi-antibiotic resistant, refractory to the available therapies and equipped with a variety of pathogenicity determinants. This bacterium uses quorum-sensing systems to regulate its physiological processes, including the expression of virulence traits, to adapt and proliferate within a host. Here, we describe the construction and application of two bioluminescence-based reporter systems for the direct detection of the quorum-sensing regulated expression of (i) the gelatinase biosynthesis-activating pheromone (GBAP) and (ii) the cytolysin small subunit (CylLS) in natural samples. The two E. faecalis reporters conditionally expressed bioluminescence in the presence of GBAP and CylLS both in the supernatants of liquid cultures and in an agar-overlay assay in as little as three hours, with a high level of sensitivity. Biosensors employed to investigate the interaction between the fsr and cyl systems revealed that fsr impeded CylLS activity by 75%. Furthermore, we identified a clinical E. faecalis isolate that acted as a biological cheater, producing cytolysin only upon sensing CylLS-producers in its environment. This isolate enhanced its virulence during polymicrobial systemic infection of Galleria mellonella. PMID:25661457

  9. Zinc deficiency increases organ damage and mortality in a murine model of polymicrobial sepsis

    PubMed Central

    Knoell, Daren L.; Julian, Mark W.; Bao, Shengying; Besecker, Beth; Macre, Jennifer E.; Leikauf, George D.; DiSilvestro, Robert A.; Crouser, Elliott D.

    2010-01-01

    Objective Zinc deficiency is common among populations at high risk for sepsis mortality, including elderly, alcoholic, and hospitalized patients. Zinc deficiency causes exaggerated inflammatory responses to endotoxin but has not been evaluated during bacterial sepsis. We hypothesized that subacute zinc deficiency would amplify immune responses and oxidant stress during bacterial sepsis [i.e., cecal ligation and puncture (CLP)] resulting in increased mortality and that acute nutritional repletion of zinc would be beneficial. Design Prospective, randomized, controlled animal study. Setting University medical center research laboratory. Subjects Adult male C57BL/6 mice. Interventions Ten-week-old, male, C57BL/6 mice were randomized into three dietary groups: 1) control diet, 2) zinc-deficient diet for 3 weeks, and 3) zinc-deficient diet for 3 weeks followed by oral zinc supplementation for 3 days (n = 35 per diet). Mice were then assigned to receive either CLP or sham operation (n = 15 each per diet). CLP and sham-operated treatment groups were further assigned to a 7-day survival study (n = 10 per treatment per diet) or were evaluated at 24 hours (n = 5 per treatment per diet) for signs of vital organ damage. Measurements and Main Results Sepsis mortality was significantly increased with zinc deficiency (90% vs. 30% on control diet). Zinc-deficient animals subject to CLP had higher plasma cytokines, more severe organ injury, including increased oxidative tissue damage and cell death, particularly in the lungs and spleen. None of the sham-operated animals died or developed signs of organ damage. Zinc supplementation normalized the inflammatory response, greatly diminished tissue damage, and significantly reduced mortality. Conclusions Subacute zinc deficiency significantly increases systemic inflammation, organ damage, and mortality in a murine polymicrobial sepsis model. Short-term zinc repletion provides significant, but incomplete protection despite normalization

  10. Diversity in a Polymicrobial Community Revealed by Analysis of Viromes, Endolysins and CRISPR Spacers.

    PubMed

    Davison, Michelle; Treangen, Todd J; Koren, Sergey; Pop, Mihai; Bhaya, Devaki

    2016-01-01

    The polymicrobial biofilm communities in Mushroom and Octopus Spring in Yellowstone National Park (YNP) are well characterized, yet little is known about the phage populations. Dominant species, Synechococcus sp. JA-2-3B'a(2-13), Synechococcus sp. JA-3-3Ab, Chloroflexus sp. Y-400-fl, and Roseiflexus sp. RS-1, contain multiple CRISPR-Cas arrays, suggesting complex interactions with phage predators. To analyze phage populations from Octopus Spring biofilms, we sequenced a viral enriched fraction. To assemble and analyze phage metagenomic data, we developed a custom module, VIRITAS, implemented within the MetAMOS framework. This module bins contigs into groups based on tetranucleotide frequencies and CRISPR spacer-protospacer matching and ORF calling. Using this pipeline we were able to assemble phage sequences into contigs and bin them into three clusters that corroborated with their potential host range. The virome contained 52,348 predicted ORFs; some were clearly phage-like; 9319 ORFs had a recognizable Pfam domain while the rest were hypothetical. Of the recognized domains with CRISPR spacer matches, was the phage endolysin used by lytic phage to disrupt cells. Analysis of the endolysins present in the thermophilic cyanophage contigs revealed a subset of characterized endolysins as well as a Glyco_hydro_108 (PF05838) domain not previously associated with sequenced cyanophages. A search for CRISPR spacer matches to all identified phage endolysins demonstrated that a majority of endolysin domains were targets. This strategy provides a general way to link host and phage as endolysins are known to be widely distributed in bacteriophage. Endolysins can also provide information about host cell wall composition and have the additional potential to be used as targets for novel therapeutics.

  11. Model of Polymicrobial Peritonitis That Induces the Proinflammatory and Immunosuppressive Phases of Sepsis ▿

    PubMed Central

    Barrera, Gabriela; Landoni, Verónica; Martire-Greco, Daiana; Chiarella, Paula; Meiss, Roberto; Gómez, Sonia A.; Alves-Rosa, Fernanda; Rearte, Barbara; Isturiz, Martín; Palermo, Marina S.; Fernández, Gabriela C.

    2011-01-01

    Severe sepsis is associated with early release of inflammatory mediators that contribute to the morbidity and mortality observed during the first stages of this syndrome. Although sepsis is a deadly, acute disease, high mortality rates have been observed in patients displaying evidence of sepsis-induced immune deactivation. Although the contribution of experimental models to the knowledge of pathophysiological and therapeutic aspects of human sepsis is undeniable, most of the current studies using animal models have focused on the acute, proinflammatory phase. We developed a murine model that reproduces the early acute phases but also the long-term consequences of human sepsis. We induced polymicrobial acute peritonitis (AP) by establishing a surgical connection between the cecum and the peritoneum, allowing the exit of intestinal bacteria. Using this model, we observed an acute phase with high mortality, leukopenia, increased interleukin-6 levels, bacteremia, and neutrophil activation. A peak of leukocytosis on day 9 or 10 revealed the persistence of the infection within the lung and liver, with inflammatory hepatic damage being shown by histological examination. Long-term (20 days) derangements in both innate and adaptive immune responses were found, as demonstrated by impaired systemic tumor necrosis factor alpha production in response to an inflammatory stimulus; a decreased primary humoral immune response and T cell proliferation, associated with an increased number of myeloid suppressor cells (Gr-1+ CD11b+) in the spleen; and a low clearance capacity. This model provides a good approach to attempt novel therapeutic interventions directed to augmenting host immunity during late sepsis. PMID:21173307

  12. The burden of comorbidity is associated with symptomatic polymicrobial urinary tract infection among institutionalized elderly.

    PubMed

    Laudisio, Alice; Marinosci, Felice; Fontana, Davide; Gemma, Antonella; Zizzo, Alessandro; Coppola, Anna; Rodano, Leonardo; Antonelli Incalzi, Raffaele

    2015-12-01

    Urinary tract infections (UTIs), often sustained by polymicrobial flora (p-UTIs), are a common finding among nursing home patients, and associated with adverse outcomes and increased healthcare costs. P-UTIs have been extensively studied with regard to microbiological aspects. However, little is known about the characteristics of the host. The aim of this study is to verify to which extent comorbidity characterizes elderly nursing home patients with p-UTIs. We enrolled 299 patients with culture-positive UTI consecutively admitted to the nursing home of the "Fondazione San Raffaele Cittadella della Carità", Taranto, Italy. P-UTI was diagnosed when two uropathogens were simultaneously isolated. The burden of comorbidity was quantified using the Charlson comorbidity score index. Logistic regression analysis was used to assess the adjusted association of the variables of interest with the presence of p-UTI. P-UTIs were detected in 118/299 (39%) patients. According to logistic regression, the presence of p-UTIs was independently associated with the Charlson index (OR 1.70; 95% CI 1.06-2.72; P = .026). This association remained also after excluding participants without urinary catheter (OR 1.88; 95% CI 1.13-3.11; P = .015). The presence of P-UTIs is associated with the burden of comorbidity, but not with individual diseases. Older nursing home patients with comorbidity should be screened for the presence of p-UTIs; further studies are needed to evaluate the impact of early detection and treatment of p-UTIs on the development of comorbidity.

  13. High-Level Vancomycin-Resistant Staphylococcus aureus Isolates Associated with a Polymicrobial Biofilm▿

    PubMed Central

    Weigel, Linda M.; Donlan, Rodney M.; Shin, Dong Hyeon; Jensen, Bette; Clark, Nancye C.; McDougal, Linda K.; Zhu, Wenming; Musser, Kimberlee A.; Thompson, Jill; Kohlerschmidt, Donna; Dumas, Nellie; Limberger, Ronald J.; Patel, Jean B.

    2007-01-01

    Glycopeptides such as vancomycin are the treatment of choice for infections due to methicillin-resistant Staphylococcus aureus. This study describes the identification of high-level vancomycin-resistant S. aureus (VRSA) isolates in a polymicrobial biofilm within an indwelling nephrostomy tube in a patient in New York. S. aureus, Enterococcus faecalis, Enterococcus faecium, Micrococcus species, Morganella morganii, and Pseudomonas aeruginosa were isolated from the biofilm. For VRSA isolates, vancomycin MICs ranged from 32 to >128 μg/ml. VRSA isolates were also resistant to aminoglycosides, fluoroquinolones, macrolides, penicillin, and tetracycline but remained susceptible to chloramphenicol, linezolid, rifampin, and trimethoprim-sulfamethoxazole. The vanA gene was localized to a plasmid of ∼100 kb in VRSA and E. faecium isolates from the biofilm. Plasmid analysis revealed that the VRSA isolate acquired the 100-kb E. faecium plasmid, which was then maintained without integration into the MRSA plasmid. The tetracycline resistance genes tet(U) and tet(S), not previously detected in S. aureus isolates, were identified in the VRSA isolates. Additional resistance elements in the VRSA isolate included a multiresistance gene cluster, ermB-aadE-sat4-aphA-3, msrA (macrolide efflux), and the bifunctional aminoglycoside resistance gene aac(6′)-aph(2")-Ia. Multiple combinations of resistance genes among the various isolates of staphylococci and enterococci, including vanA, tet(S), and tet(U), illustrate the dynamic nature of gene acquisition and loss within and between bacterial species throughout the course of infection. The potential for interspecies transfer of antimicrobial resistance genes, including resistance to vancomycin, may be enhanced by the microenvironment of a biofilm. PMID:17074796

  14. Diversity in a Polymicrobial Community Revealed by Analysis of Viromes, Endolysins and CRISPR Spacers

    PubMed Central

    Treangen, Todd J.; Koren, Sergey; Pop, Mihai; Bhaya, Devaki

    2016-01-01

    The polymicrobial biofilm communities in Mushroom and Octopus Spring in Yellowstone National Park (YNP) are well characterized, yet little is known about the phage populations. Dominant species, Synechococcus sp. JA-2-3B'a(2–13), Synechococcus sp. JA-3-3Ab, Chloroflexus sp. Y-400-fl, and Roseiflexus sp. RS-1, contain multiple CRISPR-Cas arrays, suggesting complex interactions with phage predators. To analyze phage populations from Octopus Spring biofilms, we sequenced a viral enriched fraction. To assemble and analyze phage metagenomic data, we developed a custom module, VIRITAS, implemented within the MetAMOS framework. This module bins contigs into groups based on tetranucleotide frequencies and CRISPR spacer-protospacer matching and ORF calling. Using this pipeline we were able to assemble phage sequences into contigs and bin them into three clusters that corroborated with their potential host range. The virome contained 52,348 predicted ORFs; some were clearly phage-like; 9319 ORFs had a recognizable Pfam domain while the rest were hypothetical. Of the recognized domains with CRISPR spacer matches, was the phage endolysin used by lytic phage to disrupt cells. Analysis of the endolysins present in the thermophilic cyanophage contigs revealed a subset of characterized endolysins as well as a Glyco_hydro_108 (PF05838) domain not previously associated with sequenced cyanophages. A search for CRISPR spacer matches to all identified phage endolysins demonstrated that a majority of endolysin domains were targets. This strategy provides a general way to link host and phage as endolysins are known to be widely distributed in bacteriophage. Endolysins can also provide information about host cell wall composition and have the additional potential to be used as targets for novel therapeutics. PMID:27611571

  15. Bighorn sheep pneumonia: sorting out the cause of a polymicrobial disease.

    PubMed

    Besser, Thomas E; Frances Cassirer, E; Highland, Margaret A; Wolff, Peregrine; Justice-Allen, Anne; Mansfield, Kristin; Davis, Margaret A; Foreyt, William

    2013-02-01

    Pneumonia of bighorn sheep (Ovis canadensis) is a dramatic disease of high morbidity and mortality first described more than 80 years ago. The etiology of the disease has been debated since its initial discovery, and at various times lungworms, Mannheimia haemolytica and other Pasteurellaceae, and Mycoplasma ovipneumoniae have been proposed as primary causal agents. A multi-factorial "respiratory disease complex" has also been proposed as confirmation of causation has eluded investigators. In this paper we review the evidence for each of the candidate primary agents with regard to causal criteria including strength of association, temporality, plausibility, experimental evidence, and analogy. While we find some degree of biological plausibility for all agents and strong experimental evidence for M. haemolytica, we demonstrate that of the alternatives considered, M. ovipneumoniae is the best supported by all criteria and is therefore the most parsimonious explanation for the disease. The strong but somewhat controversial experimental evidence implicating disease transmission from domestic sheep is consistent with this finding. Based on epidemiologic and microbiologic data, we propose that healthy bighorn sheep populations are naïve to M. ovipneumoniae, and that its introduction to susceptible bighorn sheep populations results in epizootic polymicrobial bacterial pneumonia often followed by chronic infection in recovered adults. If this hypothesized model is correct, efforts to control this disease by development or application of vectored vaccines to Pasteurellaceae are unlikely to provide significant benefits, whereas efforts to ensure segregation of healthy bighorn sheep populations from M. ovipneumoniae-infected reservoir hosts are crucial to prevention of new disease epizootics. It may also be possible to develop M. ovipneumoniae vaccines or other management strategies that could reduce the impact of this devastating disease in bighorn sheep. Copyright © 2012

  16. Zinc dyshomeostasis during polymicrobial sepsis in mice involves zinc transporter Zip14 and can be overcome by zinc supplementation

    PubMed Central

    Wessels, Inga

    2015-01-01

    Integrity of the immune system is particularly dependent on the availability of zinc. Recent data suggest that zinc is involved in the development of sepsis, a life-threatening systemic inflammation with high death rates, but with limited therapeutic options. Altered cell zinc transport mechanisms could contribute to the inflammatory effects of sepsis. Zip14, a zinc importer induced by proinflammatory stimuli, could influence zinc metabolism during sepsis and serve as a target for therapy. Using cecal ligation-and-puncture (CLP) to model polymicrobial sepsis, we narrowed the function of ZIP14 to regulation of zinc homeostasis in hepatocytes, while hepatic leukocytes were mostly responsible for driving inflammation, as shown by higher expression of IL-1β, TNFα, S100A8, and matrix metalloproteinase-8. Using Zip14 knockout (KO) mice as a novel approach, we found that ablation of Zip14 produced a delay in development of leukocytosis, prevented zinc accumulation in the liver, altered the kinetics of hypozincemia, and drastically increased serum IL-6, TNFα, and IL-10 concentrations following CLP. Hence, this model revealed that the zinc transporter ZIP14 is a component of the pathway for zinc redistribution that contributes to zinc dyshomeostasis during polymicrobial sepsis. In contrast, using the identical CLP model, we found that supplemental dietary zinc reduced the severity of sepsis, as shown by amelioration of cytokines, calprotectins, and blood bacterial loads. We conclude that the zinc transporter ZIP14 influences aspects of the pathophysiology of nonlethal polymicrobial murine sepsis induced by CLP through zinc delivery. The results are promising for the use of zinc and its transporters as targets for future sepsis therapy. PMID:26272258

  17. Could Externalized St. Jude Medical Riata® Lead Be a Culture Medium of a Polymicrobial Endocarditis? A Clinical Case

    PubMed Central

    Trotta, Roberta; Mandurino, Cosimo; Pinto, Mariangela; Luzzi, Giovanni; Favale, Stefano

    2017-01-01

    We report the case of a man affected by polymicrobial endocarditis developed on a St. Jude Medical Riata lead with a malfunction because of the outsourcing of conductors. The patient was treated with antibiotic targeted therapy and showed different bacteria at the blood cultures and then underwent transvenous leads extraction. Vegetations were highlighted on the caval, atrial, and ventricular tracts of the Riata lead, but the cultures were all negative. The externalization of Riata lead may cause the malfunction but it could also promote bacterial colonies and vegetations. In conclusion, looking for early signs of infection is mandatory during Riata leads follow-up checks. PMID:28191354

  18. Genome-wide transposon mutagenesis of Proteus mirabilis: Essential genes, fitness factors for catheter-associated urinary tract infection, and the impact of polymicrobial infection on fitness requirements

    PubMed Central

    Smith, Sara N.; Zhao, Lili; Wu, Weisheng

    2017-01-01

    The Gram-negative bacterium Proteus mirabilis is a leading cause of catheter-associated urinary tract infections (CAUTIs), which are often polymicrobial. Numerous prior studies have uncovered virulence factors for P. mirabilis pathogenicity in a murine model of ascending UTI, but little is known concerning pathogenesis during CAUTI or polymicrobial infection. In this study, we utilized five pools of 10,000 transposon mutants each and transposon insertion-site sequencing (Tn-Seq) to identify the full arsenal of P. mirabilis HI4320 fitness factors for single-species versus polymicrobial CAUTI with Providencia stuartii BE2467. 436 genes in the input pools lacked transposon insertions and were therefore concluded to be essential for P. mirabilis growth in rich medium. 629 genes were identified as P. mirabilis fitness factors during single-species CAUTI. Tn-Seq from coinfection with P. stuartii revealed 217/629 (35%) of the same genes as identified by single-species Tn-Seq, and 1353 additional factors that specifically contribute to colonization during coinfection. Mutants were constructed in eight genes of interest to validate the initial screen: 7/8 (88%) mutants exhibited the expected phenotypes for single-species CAUTI, and 3/3 (100%) validated the expected phenotypes for polymicrobial CAUTI. This approach provided validation of numerous previously described P. mirabilis fitness determinants from an ascending model of UTI, the discovery of novel fitness determinants specifically for CAUTI, and a stringent assessment of how polymicrobial infection influences fitness requirements. For instance, we describe a requirement for branched-chain amino acid biosynthesis by P. mirabilis during coinfection due to high-affinity import of leucine by P. stuartii. Further investigation of genes and pathways that provide a competitive advantage during both single-species and polymicrobial CAUTI will likely provide robust targets for therapeutic intervention to reduce P. mirabilis

  19. Genome-wide transposon mutagenesis of Proteus mirabilis: Essential genes, fitness factors for catheter-associated urinary tract infection, and the impact of polymicrobial infection on fitness requirements.

    PubMed

    Armbruster, Chelsie E; Forsyth-DeOrnellas, Valerie; Johnson, Alexandra O; Smith, Sara N; Zhao, Lili; Wu, Weisheng; Mobley, Harry L T

    2017-06-01

    The Gram-negative bacterium Proteus mirabilis is a leading cause of catheter-associated urinary tract infections (CAUTIs), which are often polymicrobial. Numerous prior studies have uncovered virulence factors for P. mirabilis pathogenicity in a murine model of ascending UTI, but little is known concerning pathogenesis during CAUTI or polymicrobial infection. In this study, we utilized five pools of 10,000 transposon mutants each and transposon insertion-site sequencing (Tn-Seq) to identify the full arsenal of P. mirabilis HI4320 fitness factors for single-species versus polymicrobial CAUTI with Providencia stuartii BE2467. 436 genes in the input pools lacked transposon insertions and were therefore concluded to be essential for P. mirabilis growth in rich medium. 629 genes were identified as P. mirabilis fitness factors during single-species CAUTI. Tn-Seq from coinfection with P. stuartii revealed 217/629 (35%) of the same genes as identified by single-species Tn-Seq, and 1353 additional factors that specifically contribute to colonization during coinfection. Mutants were constructed in eight genes of interest to validate the initial screen: 7/8 (88%) mutants exhibited the expected phenotypes for single-species CAUTI, and 3/3 (100%) validated the expected phenotypes for polymicrobial CAUTI. This approach provided validation of numerous previously described P. mirabilis fitness determinants from an ascending model of UTI, the discovery of novel fitness determinants specifically for CAUTI, and a stringent assessment of how polymicrobial infection influences fitness requirements. For instance, we describe a requirement for branched-chain amino acid biosynthesis by P. mirabilis during coinfection due to high-affinity import of leucine by P. stuartii. Further investigation of genes and pathways that provide a competitive advantage during both single-species and polymicrobial CAUTI will likely provide robust targets for therapeutic intervention to reduce P. mirabilis

  20. Therapeutic benefits of the group B3 vitamin nicotinamide in mice with lethal endotoxemia and polymicrobial sepsis.

    PubMed

    Yuan, Hongmei; Wan, Jingyuan; Li, Longjiang; Ge, Pu; Li, Hongzhong; Zhang, Li

    2012-03-01

    Nicotinamide (NAM) is a group B3 vitamin involved in a wide range of biological processes. Recently, the anti-inflammatory properties of NAM have been revealed. In this study, we investigated the therapeutic effects of NAM in murine models of endotoxemia and sepsis. Endotoxemic liver injury was induced by intraperitoneal injection of lipopolysaccharide (LPS) into D-galactosamine (D-Gal)-sensitized mice. Lethal endotoxemia was induced by intraperitoneal administration of LPS at a dose of 20 mg/kg. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP). In mice challenged with LPS/D-Gal, treatment with NAM significantly deceased serum aminotransferases level and alleviated hepatic lesions. NAM also reduced serum tumor necrosis factor-α level and attenuated apoptosis in liver, as assessed by terminal deoxynucleotidyl transferase-mediated nucleotide nick end labeling (TUNEL) staining and measurements of caspases activities. Survival analysis indicated that NAM reduced the mortality rate of LPS/D-Gal-challenged mice. In mice with lethal endotoxemia, NAM reduced serum level of pro-inflammatory cytokines and multiple organ damage as evidence by improved morphological lesion, reduced lung wet to dry ratio as well as decreased serum level of aminotransferase and blood urea nitrogen. In survival analysis, treatment with NAM increased the survival rate of mice with lethal endotoxemia or CLP-induced polymicrobial sepsis. Taken together, treatment with NAM might provide therapeutic benefits in sepsis, which attenuated inflammatory injury and improved the survival rate.

  1. Trichinella spiralis Excretory-Secretory Products Protect against Polymicrobial Sepsis by Suppressing MyD88 via Mannose Receptor

    PubMed Central

    Du, Linlin; Liu, Lihua; Yu, Yang; Shan, Hui; Li, Leiqing

    2014-01-01

    Trichinella spiralis (T. spiralis) or its excretory-secretory products (TsES) protect hosts from autoimmune diseases, which depend on inducing host T helper (Th) 2 immune response and inhibiting inflammatory factors. Sepsis is a systemic inflammatory response syndrome (SIRS) evoked by infection. Little is known about the effects of helminths or their excretory-secretory products on sepsis. Here, we investigated the effects of TsES in a mice model of polymicrobial sepsis. TsES improved survival, reduced organ injury, and enhanced bacterial clearance in septic mice. To investigate the molecular mechanism, macrophages from septic patients or the control group were incubated with TsES. TsES reduced sepsis-inducing inflammatory cytokines mediated by Toll-like receptors (TLR) in vitro by suppressing TLR adaptor-transducer myeloid differentiation factor 88 (MyD88) and nuclear factor- (NF-)-κB. Furthermore, TsES upregulated mannose receptor (MR) expression during sepsis. MR blocking attenuated the effects of TsES on MyD88 and NF-κB expression. In vivo, MR RNAi reduced the survival rate of septic mice treated with TsES, suggesting that TsES-mediated protection against polymicrobial sepsis is dependent on MR. Thus, TsES administration might be a potential therapeutic strategy for treating sepsis. PMID:25054155

  2. Trichinella spiralis excretory-secretory products protect against polymicrobial sepsis by suppressing MyD88 via mannose receptor.

    PubMed

    Du, Linlin; Liu, Lihua; Yu, Yang; Shan, Hui; Li, Leiqing

    2014-01-01

    Trichinella spiralis (T. spiralis) or its excretory-secretory products (TsES) protect hosts from autoimmune diseases, which depend on inducing host T helper (Th) 2 immune response and inhibiting inflammatory factors. Sepsis is a systemic inflammatory response syndrome (SIRS) evoked by infection. Little is known about the effects of helminths or their excretory-secretory products on sepsis. Here, we investigated the effects of TsES in a mice model of polymicrobial sepsis. TsES improved survival, reduced organ injury, and enhanced bacterial clearance in septic mice. To investigate the molecular mechanism, macrophages from septic patients or the control group were incubated with TsES. TsES reduced sepsis-inducing inflammatory cytokines mediated by Toll-like receptors (TLR) in vitro by suppressing TLR adaptor-transducer myeloid differentiation factor 88 (MyD88) and nuclear factor- (NF-)-κB. Furthermore, TsES upregulated mannose receptor (MR) expression during sepsis. MR blocking attenuated the effects of TsES on MyD88 and NF-κB expression. In vivo, MR RNAi reduced the survival rate of septic mice treated with TsES, suggesting that TsES-mediated protection against polymicrobial sepsis is dependent on MR. Thus, TsES administration might be a potential therapeutic strategy for treating sepsis.

  3. Mycobacterium fortuitum and Polymicrobial Peritoneal Dialysis-Related Peritonitis: A Case Report and Review of the Literature.

    PubMed

    Hamade, Anwar; Pozdzik, Agnieszka; Denis, O; Tooulou, Monika; Keyzer, Caroline; Jacobs, F; Khabbout, Jose; Nortier, Joëlle L

    2014-01-01

    Mycobacterium fortuitum is a ubiquitous, rapidly growing nontuberculous mycobacterium (NTM). It is the most commonly reported NTM in peritoneal dialysis (PD) associated peritonitis. We report a case of a 52-year-old man on PD, who developed refractory polymicrobial peritonitis necessitating PD catheter removal and shift to hemodialysis. Thereafter, M. fortuitum was identified in the PD catheter culture and in successive cultures of initial peritoneal effluent and patient was treated with amikacin and ciprofloxacin for six months with a good and sustained clinical response. Months after completion of the course of antibiotics, the patient successfully returned to PD. To our knowledge, this is the first reported case of M. fortuitum peritonitis in the field of polymicrobial PD peritonitis. It demonstrates the diagnostic yield of pursuing further investigations in cases of refractory PD peritonitis. In a systematic review of the literature, only 20 reports of M. fortuitum PD peritonitis were identified. Similar to our case, a delay in microbiological diagnosis was frequently noted and the Tenckhoff catheter was commonly removed. However, the type and duration of antibiotic therapy varied widely making the optimal treatment unclear.

  4. Incorporation of real-time PCR into routine public health surveillance of culture negative bacterial meningitis in São Paulo, Brazil.

    PubMed

    Sacchi, Claudio T; Fukasawa, Lucila O; Gonçalves, Maria G; Salgado, Maristela M; Shutt, Kathleen A; Carvalhanas, Telma R; Ribeiro, Ana F; Kemp, Brigina; Gorla, Maria C O; Albernaz, Ricardo K; Marques, Eneida G L; Cruciano, Angela; Waldman, Eliseu A; Brandileone, M Cristina C; Harrison, Lee H

    2011-01-01

    Real-time (RT)-PCR increases diagnostic yield for bacterial meningitis and is ideal for incorporation into routine surveillance in a developing country. We validated a multiplex RT-PCR assay for Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae in Brazil. Risk factors for being culture-negative, RT-PCR positive were determined. The sensitivity of RT-PCR in cerebrospinal fluid (CSF) was 100% (95% confidence limits, 96.0%-100%) for N. meningitidis, 97.8% (85.5%-99.9%) for S. pneumoniae, and 66.7% (9.4%-99.2%) for H. influenzae. Specificity ranged from 98.9% to 100%. Addition of RT-PCR to routine microbiologic methods increased the yield for detection of S. pneumoniae, N. meningitidis, and H. influenzae cases by 52%, 85%, and 20%, respectively. The main risk factor for being culture negative and RT-PCR positive was presence of antibiotic in CSF (odds ratio 12.2, 95% CI 5.9-25.0). RT-PCR using CSF was highly sensitive and specific and substantially added to measures of meningitis disease burden when incorporated into routine public health surveillance in Brazil.

  5. Incorporation of Real-Time PCR into Routine Public Health Surveillance of Culture Negative Bacterial Meningitis in São Paulo, Brazil

    PubMed Central

    Sacchi, Claudio T.; Fukasawa, Lucila O.; Gonçalves, Maria G.; Salgado, Maristela M.; Shutt, Kathleen A.; Carvalhanas, Telma R.; Ribeiro, Ana F.; Kemp, Brigina; Gorla, Maria C. O.; Albernaz, Ricardo K.; Marques, Eneida G. L.; Cruciano, Angela; Waldman, Eliseu A.; Brandileone, M. Cristina C; Harrison, Lee H.

    2011-01-01

    Real-time (RT)-PCR increases diagnostic yield for bacterial meningitis and is ideal for incorporation into routine surveillance in a developing country. We validated a multiplex RT-PCR assay for Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae in Brazil. Risk factors for being culture-negative, RT-PCR positive were determined. The sensitivity of RT-PCR in cerebrospinal fluid (CSF) was 100% (95% confidence limits, 96.0%–100%) for N. meningitidis, 97.8% (85.5%–99.9%) for S. pneumoniae, and 66.7% (9.4%–99.2%) for H. influenzae. Specificity ranged from 98.9% to 100%. Addition of RT-PCR to routine microbiologic methods increased the yield for detection of S. pneumoniae, N. meningitidis, and H. influenzae cases by 52%, 85%, and 20%, respectively. The main risk factor for being culture negative and RT-PCR positive was presence of antibiotic in CSF (odds ratio 12.2, 95% CI 5.9-25.0). RT-PCR using CSF was highly sensitive and specific and substantially added to measures of meningitis disease burden when incorporated into routine public health surveillance in Brazil. PMID:21731621

  6. Fatal Case of Polymicrobial Meningitis Caused by Cryptococcus liquefaciens and Mycobacterium tuberculosis Complex in a Human Immunodeficiency Virus-Infected Patient.

    PubMed

    Conde-Pereira, César; Rodas-Rodríguez, Lia; Díaz-Paz, Manuel; Palacios-Rivera, Hilda; Firacative, Carolina; Meyer, Wieland; Alcázar-Castillo, Myriam

    2015-08-01

    We describe a fatal case of polymicrobial meningitis in a human immunodeficiency virus-infected patient from Guatemala caused by Cryptococcus liquefaciens and Mycobacterium tuberculosis complex. Central nervous system infections caused concurrently by these species are extremely rare. This is also the first report of disseminated disease caused by C. liquefaciens.

  7. Baicalin Improves Survival in a Murine Model of Polymicrobial Sepsis via Suppressing Inflammatory Response and Lymphocyte Apoptosis

    PubMed Central

    Zou, Yun; Bo, Lulong; Wang, Fei; Lou, Jingsheng; Fan, Xiaohua; Bao, Rui; Wu, Youping; Chen, Feng; Deng, Xiaoming; Li, Jinbao

    2012-01-01

    Background An imbalance between overwhelming inflammation and lymphocyte apoptosis is the main cause of high mortality in patients with sepsis. Baicalin, the main active ingredient of the Scutellaria root, exerts anti-inflammatory, anti-apoptotic, and even antibacterial properties in inflammatory and infectious diseases. However, the therapeutic effect of baicalin on polymicrobial sepsis remains unknown. Methodology/Principal Findings Polymicrobial sepsis was induced by cecal ligation and puncture (CLP) in C57BL/6 mice. Mice were infused with baicalin intraperitoneally at 1 h, 6 h and 12 h after CLP. Survival rates were assessed over the subsequent 8 days. Bacterial burdens in blood and peritoneal cavity were calculated to assess the bacterial clearance. Neutrophil count in peritoneal lavage fluid was also calculated. Injuries to the lung and liver were detected by hematoxylin and eosin staining. Levels of cytokines, including tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-10 and IL-17, in blood and peritoneum were measured by enzyme-linked immunosorbent assay. Adaptive immune function was assessed by apoptosis of lymphocytes in the thymus and counts of different cell types in the spleen. Baicalin significantly enhanced bacterial clearance and improved survival of septic mice. The number of neutrophils in peritoneal lavage fluid was reduced by baicalin. Less neutrophil infiltration of the lung and liver in baicalin-treated mice was associated with attenuated injuries to these organs. Baicalin significantly reduced the levels of proinflammatory cytokines but increased the level of anti-inflammatory cytokine in blood and peritoneum. Apoptosis of CD3+ T cell was inhibited in the thymus. The numbers of CD4+, CD8+ T lymphocytes and dendritic cells (DCs) were higher, while the number of CD4+CD25+ regulatory T cells was lower in the baicalin group compared with the CLP group. Conclusions/Significance Baicalin improves survival of mice with polymicrobial

  8. Effects of Carvacrol on Survival, Mesenteric Blood Flow, Aortic Function and Multiple Organ Injury in a Murine Model of Polymicrobial Sepsis.

    PubMed

    Ozer, Erdem Kamil; Goktas, Mustafa Tugrul; Toker, Aysun; Bariskaner, Hulagu; Ugurluoglu, Ceyhan; Iskit, Alper Bektas

    2017-06-23

    Carvacrol (CRV) has strong cytoprotective, antioxidant, and anti-inflammatory properties. We aimed to demonstrate the possible protective effects of CRV on survival, mesenteric artery blood flow (MBF), vascular reactivity, and oxidative and inflammatory injuries in a murine model of polymicrobial sepsis induced by cecal ligation and puncture (CLP). Wistar rats were allocated into the following four groups: Sham, CLP, Sham + CRV, and CLP + CRV. The animals were orally administered with CRV (80 mg/kg/day) or vehicle (corn oil; 1 mL/kg/day) for 7 days. At the eighth day, Sham or CLP procedure was applied. Twenty hours after the operations, MBF and contractile responses of isolated aortic preparations to phenylephrine were measured. Tissue samples were obtained for biochemical and histopathological assessments. Additionally, survival rates were recorded throughout 96 h. CRV administration improved the mesenteric perfusion, contractile function of aorta, and survival after CLP. CRV substantially prevented the elevations in the levels of LDH, BUN, Cr, and inflammatory cytokines (tumor necrosis factor-alpha, interleukin-1 beta and interleukin-6) but could not prevent the elevations of AST and ALT after CLP. The decreased liver, kidney, and spleen glutathione levels and increased liver, kidney, lung, and spleen malondialdehyde levels induced by CLP were substantially restored by CRV. Also, histopathological protective effects of CRV on multiple organ damage due to CLP were observed. CRV possesses strong ameliorative effects on sepsis due to its protective effects on mesenteric perfusion and aortic function and its antioxidative and anti-inflammatory effects.

  9. [A case of culture-negative brain abscess caused by Streptococcus intermedius infection diagnosed by broad-range PCR of 16S ribosomal RNA].

    PubMed

    Ohara, Nobuyuki; Asai, Katsunori; Ohkusu, Kiyofumi; Wakayama, Akatsuki

    2013-10-01

    A 50-year-old man presented with altered mental status during hospitalization for pneumonia. MRI showed multifocal ring-enhanced lesions, which consisted of multiple cerebral abscesses. We started empirical antibiotic therapy, but the following morning, his condition rapidly deteriorated and a CT scan revealed acute hydrocephalus, which required ventricular drainage. Gram staining of cerebro-spinal fluid from the ventricular drainage showed gram-positive cocci in chains, but culture results were negative. 16S ribosomal RNA sequencing with broad-range PCR of the cerebro-spinal fluid identified Streptococcus intermedius. On the basis of this identification, the antibiotic regimen was changed to ampicillin monotherapy. After 1 year of antibiotic therapy, all the abscesses had disappeared and the patient was discharged without any sequelae. Bacterial 16S rRNA gene analysis with broad-range PCR is a very useful method for facilitating the etiological diagnosis and selection of appropriate treatment for culture-negative infections.

  10. "Orostim"--polymicrobial preparation for oral administration. I. "In vivo" determination of toxicity and of inborn resistance stimulation characteristic.

    PubMed

    Hoişie, S; Pencea, I; Dimache, G; Lupuşoru, E C; Grigoraş, E; Oiţă, V; Buzdzgan, R; Anton, D A; Ionescu, O N; Uliciuc, S

    1989-01-01

    "Orostim" is a polymicrobial immunomodulator for oral administration, obtained from bacterial suspensions, disintegrated by ultrasonics and dried by atomization. The preparation was chemically characterized before and after atomization without presenting essential modifications. Orostim was not shown to be toxic in mice and rats by esophageal intubation, as long as 20 days. The animals presented normal evolution; hemoleukograms, serum proteins and alkaline phosphatase, in rats, did not present significant modifications in comparison with controls. Histopathologic examination of the organs, obtained from mice, treated for 20 days (liver, spleen, lung) did not emphasize modifications in comparison with controls. Circulating neutrophils phagocytosis in rabbits, orally treated with Orostim, was increased as compared to 0 time; serum complement values decreased compared to the initial ones for 0 time but turned to normal and reached even superior limits, 10 days after the treatment ending.

  11. Hydrogen sulfide and neurogenic inflammation in polymicrobial sepsis: involvement of substance P and ERK-NF-κB signaling.

    PubMed

    Ang, Seah-Fang; Moochhala, Shabbir M; MacAry, Paul A; Bhatia, Madhav

    2011-01-01

    Hydrogen sulfide (H(2)S) has been shown to induce transient receptor potential vanilloid 1 (TRPV1)-mediated neurogenic inflammation in polymicrobial sepsis. However, endogenous neural factors that modulate this event and the molecular mechanism by which this occurs remain unclear. Therefore, this study tested the hypothesis that whether substance P (SP) is one important neural element that implicates in H(2)S-induced neurogenic inflammation in sepsis in a TRPV1-dependent manner, and if so, whether H(2)S regulates this response through activation of the extracellular signal-regulated kinase-nuclear factor-κB (ERK-NF-κB) pathway. Male Swiss mice were subjected to cecal ligation and puncture (CLP)-induced sepsis and treated with TRPV1 antagonist capsazepine 30 minutes before CLP. DL-propargylglycine (PAG), an inhibitor of H(2)S formation, was administrated 1 hour before or 1 hour after sepsis, whereas sodium hydrosulfide (NaHS), an H(2)S donor, was given at the same time as CLP. Capsazepine significantly attenuated H(2)S-induced SP production, inflammatory cytokines, chemokines, and adhesion molecules levels, and protected against lung and liver dysfunction in sepsis. In the absence of H(2)S, capsazepine caused no significant changes to the PAG-mediated attenuation of lung and plasma SP levels, sepsis-associated systemic inflammatory response and multiple organ dysfunction. In addition, capsazepine greatly inhibited phosphorylation of ERK(1/2) and inhibitory κBα, concurrent with suppression of NF-κB activation even in the presence of NaHS. Furthermore, capsazepine had no effect on PAG-mediated abrogation of these levels in sepsis. Taken together, the present findings show that H(2)S regulates TRPV1-mediated neurogenic inflammation in polymicrobial sepsis through enhancement of SP production and activation of the ERK-NF-κB pathway.

  12. Synergistic effects of honey and propolis toward drug multi-resistant Staphylococcus aureus, Escherichia coli and Candida albicans isolates in single and polymicrobial cultures.

    PubMed

    Al-Waili, Noori; Al-Ghamdi, Ahmad; Ansari, Mohammad Javed; Al-Attal, Y; Salom, Khelod

    2012-01-01

    Propolis and honey are natural bee products with wide range of biological and medicinal properties. The study investigated antimicrobial activity of ethyl alcohol extraction of propolis collected from Saudi Arabia (EEPS) and from Egypt (EEPE), and their synergistic effect when used with honey. Single and polymicrobial cultures of antibiotic resistant human pathogens were tested. Staphylococcus aureus (S. aureus),), Escherichia coli (E. coli) and Candida albicans (C.albicans) were cultured in 10-100% (v/v) honey diluted in broth, or 0.08-1.0% (weight/volume) EEPS and EEPE diluted in broth. Four types of polymicrobial cultures were prepared by culturing the isolates with each other in broth (control) and broth containing various concentrations of honey or propolis. Microbial growth was assessed on solid plate media after 24 h incubation. EEPS and EEPE inhibited antibiotic resistant E.coli, and S.aureus, and C.albicans in single and polymicrobial cultures. S.aureus became more susceptible when it was cultured with E.coli or C.albicans or when all cultured together. C.albicans became more susceptible when it was cultured with S.aureus or with E.coli and S. aureus together. The presence of ethyl alcohol or honey potentiated antimicrobial effect of propolis toward entire microbes tested in single or polymicrobial cultures. EEPS had lower MIC toward E.coli and C.albicans than EEPE. When propolis was mixed with honey, EEPS showed lower MIC than EEPE. In addition, honey showed lower MIC toward entire microbes when mixed with EEPS than when it was mixed with EEPE. 1) propolis prevents the growth of the microorganisms in single and mixed microbial cultures, and has synergistic effect when used with honey or ethyl alcohol, 2) the antimicrobial property of propolis varies with geographical origin, and 3) this study will pave the way to isolate active ingredients from honey and propolis to be further tested individually or in combination against human resistant infections.

  13. Type I interferon signaling in hematopoietic cells is required for survival in mouse polymicrobial sepsis by regulating CXCL10

    PubMed Central

    Kelly-Scumpia, Kindra M.; Scumpia, Philip O.; Delano, Matthew J.; Weinstein, Jason S.; Cuenca, Alex G.; Wynn, James L.

    2010-01-01

    Type I interferon (IFN) α/β is critical for host defense. During endotoxicosis or highly lethal bacterial infections where systemic inflammation predominates, mice deficient in IFN-α/β receptor (IFNAR) display decreased systemic inflammation and improved outcome. However, human sepsis mortality often occurs during a prolonged period of immunosuppression and not from exaggerated inflammation. We used a low lethality cecal ligation and puncture (CLP) model of sepsis to determine the role of type I IFNs in host defense during sepsis. Despite increased endotoxin resistance, IFNAR−/− and chimeric mice lacking IFNAR in hematopoietic cells display increased mortality to CLP. This was not associated with an altered early systemic inflammatory response, except for decreased CXCL10 production. IFNAR−/− mice display persistently elevated peritoneal bacterial counts compared with wild-type mice, reduced peritoneal neutrophil recruitment, and recruitment of neutrophils with poor phagocytic function despite normal to enhanced adaptive immune function during sepsis. Importantly, CXCL10 treatment of IFNAR−/− mice improves survival and decreases peritoneal bacterial loads, and CXCL10 increases mouse and human neutrophil phagocytosis. Using a low lethality sepsis model, we identify a critical role of type I IFN–dependent CXCL10 in host defense during polymicrobial sepsis by increasing neutrophil recruitment and function. PMID:20071504

  14. Vitamin B6 Reduces Neurochemical and Long-Term Cognitive Alterations After Polymicrobial Sepsis: Involvement of the Kynurenine Pathway Modulation.

    PubMed

    Danielski, Lucinéia Gainski; Giustina, Amanda Della; Goldim, Mariana Pereira; Florentino, Drielly; Mathias, Khiany; Garbossa, Leandro; de Bona Schraiber, Rosiane; Laurentino, Ana Olívia Martins; Goulart, Marina; Michels, Monique; de Queiroz, Karina Barbosa; Kohlhof, Markus; Rezin, Gislaine Tezza; Fortunato, Jucélia Jeremias; Quevedo, Joao; Barichello, Tatiana; Dal-Pizzol, Felipe; Coimbra, Roney S; Petronilho, Fabricia

    2017-09-06

    Neurological dysfunction as a result of neuroinflammation has been reported in sepsis and cause high mortality. High levels of cytokines stimulate the formation of neurotoxic metabolites by kynurenine (KYN) pathway. Vitamin B6 (vit B6) has anti-inflammatory and antioxidant properties and also acts as a cofactor for enzymes of the KYN pathway. Thus, by using a relevant animal model of polymicrobial sepsis, we studied the effect of vit B6 on the KYN pathway, acute neurochemical and neuroinflammatory parameters, and cognitive dysfunction in rats. Male Wistar rats (250-300 g) were submitted to cecal ligation and perforation (CLP) and divided into sham + saline, sham + vit B6, CLP + saline, and CLP + vit B6 (600 mg/kg, s.c.) groups. Twenty-four hours later, the prefrontal cortex and hippocampus were removed for neurochemical and neuroinflammatory analyses. Animals were followed for 10 days to determine survival rate, when cognitive function was assessed by behavioral tests. Vitamin B6 interfered in the activation of kynurenine pathway, which led to an improvement in neurochemical and neuroinflammatory parameters and, consequently, in the cognitive functions of septic animals. Thus, the results indicate that vit B6 exerts neuroprotective effects in acute and late consequences after sepsis.

  15. Therapeutic Effects of Treatment with Anti-TLR2 and Anti-TLR4 Monoclonal Antibodies in Polymicrobial Sepsis.

    PubMed

    Lima, Cristiano Xavier; Souza, Danielle Gloria; Amaral, Flavio Almeida; Fagundes, Caio Tavares; Rodrigues, Irla Paula Stopa; Alves-Filho, Jose Carlos; Kosco-Vilbois, Marie; Ferlin, Walter; Shang, Limin; Elson, Greg; Teixeira, Mauro Martins

    2015-01-01

    Toll-like receptors (TLRs) play an important role in the recognition of microbial products and in host defense against infection. However, the massive release of inflammatory mediators into the bloodstream following TLR activation following sepsis is thought to contribute to disease pathogenesis. Here, we evaluated the effects of preventive or therapeutic administration of monoclonal antibodies (mAbs) targeting either TLR2 or TLR4 in a model of severe polymicrobial sepsis induced by cecal ligation and puncture in mice. Pre-treatment with anti-TLR2 or anti-TLR4 mAb alone showed significant protection from sepsis-associated death. Protective effects were observed even when the administration of either anti-TLR2 or anti-TLR4 alone was delayed (i.e., 3 h after sepsis induction). Delayed administration of either mAb in combination with antibiotics resulted in additive protection. Although attempts to translate preclinical findings to clinical sepsis have failed so far, our preclinical experiments strongly suggest that there is a sufficient therapeutic window within which patients with ongoing sepsis could benefit from combined antibiotic plus anti-TLR2 or anti-TLR4 mAb treatment.

  16. Short communication: polymicrobial community in teeth associated with severe early-childhood caries.

    PubMed

    de Paula, V A; Ferreira, D C; Carmo, F L; Rosardio, A S; Dos Santos, K R; Maia, L C; Primo, L G

    2011-10-01

    This was to characterise the microbial diversity in the complex dental plaque of children with severe early-childhood caries (S-ECC), using the denaturing gel gradient electrophoresis (DGGE) technique. The DGGE technique was used as a diagnostic tool to analyse samples from the oral cavity of a patient with S-ECC. Dental plaque samples from a 3-year-old child with S-ECC were taken from the primary central maxillary incisor (biofilm on vestibular surface), primary maxillary molar (biofilm on vestibular surface), primary central maxillary incisor (dentine), primary maxillary molar (dentine) and saliva and then analysed by PCR-DGGE. Three bands occurred in all samples, moreover, 86% of similarity was observed in the pattern of bands between incisor and molar teeth biofilm samples, including four similar bands. DGGE is a valuable tool for differentiating the microbial composition of the oral plaque in S-ECC children.

  17. Polymicrobial subdural empyema: involvement of Streptococcus pneumoniae revealed by lytA PCR and antigen detection.

    PubMed

    Greve, Thomas; Clemmensen, Dorte; Ridderberg, Winnie; Pedersen, Lisbeth N; Møller, Jens K

    2011-03-01

    The authors report a case of a subdural empyema (SDE) caused by a coinfection with Streptococcus intermedius and Streptococcus pneumoniae, initially considered a S. intermedius infection only. An otherwise healthy 11-year-old female was admitted to the hospital after 5 days of illness. Symptoms were consistent with classical SDE symptoms and progressed rapidly with finally somnolence before the first neurosurgical procedure despite relevant antibiotic treatment. Primary MRI showed an interhemispheric SDE and a postoperative control CT scan showed progression of the empyema infratentorially. The empyema was evacuated twice, day 8 and 18, with good results. Primary samples showed growth of S. intermedius only. The severity of the clinical picture elicited supplementary samples, which were additionally positive for S. pneumoniae by an in-house specific lytA PCR and/or a commercial antigen test.

  18. Prevalence of streptococci and increased polymicrobial diversity associated with cystic fibrosis patient stability.

    PubMed

    Filkins, L M; Hampton, T H; Gifford, A H; Gross, M J; Hogan, D A; Sogin, M L; Morrison, H G; Paster, B J; O'Toole, G A

    2012-09-01

    Diverse microbial communities chronically colonize the lungs of cystic fibrosis patients. Pyrosequencing of amplicons for hypervariable regions in the 16S rRNA gene generated taxonomic profiles of bacterial communities for sputum genomic DNA samples from 22 patients during a state of clinical stability (outpatients) and 13 patients during acute exacerbation (inpatients). We employed quantitative PCR (qPCR) to confirm the detection of Pseudomonas aeruginosa and Streptococcus by the pyrosequencing data and human oral microbe identification microarray (HOMIM) analysis to determine the species of the streptococci identified by pyrosequencing. We show that outpatient sputum samples have significantly higher bacterial diversity than inpatients, but maintenance treatment with tobramycin did not impact overall diversity. Contrary to the current dogma in the field that Pseudomonas aeruginosa is the dominant organism in the majority of cystic fibrosis patients, Pseudomonas constituted the predominant genera in only half the patient samples analyzed and reported here. The increased fractional representation of Streptococcus in the outpatient cohort relative to the inpatient cohort was the strongest predictor of clinically stable lung disease. The most prevalent streptococci included species typically associated with the oral cavity (Streptococcus salivarius and Streptococcus parasanguis) and the Streptococcus milleri group species. These species of Streptococcus may play an important role in increasing the diversity of the cystic fibrosis lung environment and promoting patient stability.

  19. Polymicrobial Gardnerella biofilm resists repeated intravaginal antiseptic treatment in a subset of women with bacterial vaginosis: a preliminary report.

    PubMed

    Swidsinski, Alexander; Loening-Baucke, Vera; Swidsinski, Sonja; Verstraelen, Hans

    2015-03-01

    Bacterial vaginosis is a recalcitrant polymicrobial biofilm infection that often resists standard antibiotic treatment. We therefore considered repeated treatment with octenidine, a local antiseptic that has previously been shown to be highly effective in several biofilm-associated infections. Twenty-four patients with recurrent BV were treated with a 7-day course of octenidine (octenidine dihydrochloride spray application with the commercial product Octenisept). In case of treatment failure or relapse within 6 months, patients were re-treated with a 28-day course of octenidine. In case of recurrence within 6 months after the second treatment course, patients were treated again with a 28-day course followed by weekly applications for 2 months. Treatment effect was evaluated by assessment of the presence of the biofilm on voided vaginal epithelial cells through fluorescence in situ hybridisation. The initial cure rate following a 7-day course of octenidine was as high as 87.5%. The 6-month relapse rate was, however, as high as 66.6%. Repeated treatment for 28 days led to an overall cure rate of 75.0%; however, it was also associated with emergence of complete resistance to octenidine in a subset of women. The overall cure rate after three treatment courses with 1-year follow-up was 62.5 %, with 37.5 % of the patients showing complete resistance to octenidine. Our preliminary results showed that octenidine dihydrochloride was initially highly effective, but the efficacy of repeated and prolonged treatment dropped quickly as challenge with the antiseptic rapidly led to bacterial resistance in a considerable subset of women.

  20. Lysozyme-modified probiotic components protect rats against polymicrobial sepsis: role of macrophages and cathelicidin-related innate immunity.

    PubMed

    Bu, Heng-Fu; Wang, Xiao; Zhu, Ya-Qin; Williams, Roxanne Y; Hsueh, Wei; Zheng, Xiaotian; Rozenfeld, Ranna A; Zuo, Xiu-Li; Tan, Xiao-Di

    2006-12-15

    Severe sepsis is associated with dysfunction of the macrophage/monocyte, an important cellular effector of the innate immune system. Previous investigations suggested that probiotic components effectively enhance effector cell functions of the immune system in vivo. In this study, we produced bacteria-free, lysozyme-modified probiotic components (LzMPC) by treating the probiotic bacteria, Lactobacillus sp., with lysozyme. We showed that oral delivery of LzMPC effectively protected rats against lethality from polymicrobial sepsis induced by cecal ligation and puncture. We found that orally administrated LzMPC was engulfed by cells such as macrophages in the liver after crossing the intestinal barrier. Moreover, LzMPC-induced protection was associated with an increase in bacterial clearance in the liver. In vitro, LzMPC up-regulated the expression of cathelicidin-related antimicrobial peptide (CRAMP) in macrophages and enhanced bactericidal activity of these cells. Furthermore, we demonstrated that surgical stress or cecal ligation and puncture caused a decrease in CRAMP expression in the liver, whereas enteral administration of LzMPC restored CRAMP gene expression in these animals. Using a neutralizing Ab, we showed that protection against sepsis by LzMPC treatment required endogenous CRAMP. In addition, macrophages from LzMPC-treated rats had an enhanced capacity of cytokine production in response to LPS or LzMPC stimulation. Together, our data suggest that the protective effect of LzMPC in sepsis is related to an enhanced cathelicidin-related innate immunity in macrophages. Therefore, LzMPC, a novel probiotic product, is a potent immunomodulator for macrophages and may be beneficial for the treatment of sepsis.

  1. Therapeutic Potential of Cerium Oxide Nanoparticles for the Treatment of Peritonitis Induced by Polymicrobial Insult in Sprague-Dawley Rats.

    PubMed

    Manne, Nandini D P K; Arvapalli, Ravikumar; Nepal, Niraj; Thulluri, Srinivasarao; Selvaraj, Vellaisamy; Shokuhfar, Tolou; He, Kun; Rice, Kevin M; Asano, Shinichi; Maheshwari, Mani; Blough, Eric R

    2015-11-01

    Peritonitis is a life-threatening disease that is associated with high mortality. The purpose of this study was to determine if cerium oxide nanoparticles can be used to diminish intra-abdominal infection-induced mortality and systemic inflammatory response syndrome in the laboratory rat. Randomized, controlled animal study and cell culture study. University research laboratory. Male Sprague-Dawley rats aged 12 weeks, RAW 246.7 macrophage cell line. Intra-abdominal infection or peritonitis was induced by intraperitoneal injection of cecal material (600 mg/kg in 5% sterile dextrose water at a dosage of 5 mL/kg) obtained from healthy donors. Rats in control and peritonitis groups received 200 μL of sterile deionized water IV via the tail vein, whereas rats in cerium oxide-only group and peritonitis+cerium oxide group received cerium oxide nanoparticles (0.5 mg/kg) IV at the time of polymicrobial injection. Survival rate was monitored for 14 days, while in other experiments, animals were killed at 3 and 18 hours after induction of peritonitis for biochemical analysis. Administration of a single dose (0.5 mg/kg) of cerium oxide nanoparticles IV to rats in the peritonitis group significantly improved survival rates and functioned to restore core body temperature toward baseline. Treatment-induced increases in animal survivability were associated with reduced systemic and hepatic oxidative stress, diminished serum cytokines, and chemokine levels. Changes in serum inflammatory markers with treatment were accompanied by decreased monocyte and lymphocyte extravasation into the peritoneal cavity along with decreased infiltration of macrophages into liver. In the heart, treatment diminished extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase-Stat-3 signaling and attenuated endothelial expression of P-selectin and vascular cell adhesion molecule-1. Cerium oxide nanoparticles attenuate the systemic inflammatory response associated with peritonitis

  2. In vitro model of production of antibodies; a new approach to reveal the presence of key bacteria in polymicrobial environments.

    PubMed

    Wu, Chongcong; Nakka, Sravya; Mansouri, Sepahdar; Bengtsson, Torbjörn; Nayeri, Tayeb; Nayeri, Fariba

    2016-09-09

    There is a rapid emergence of multiple resistant gram-negative bacteria due to overuse of antibiotics in the treatment of infections. Biofilms consist of polymicrobial communities that survive the host's defense system. The key bacteria in biofilms are slow growing and support an attachment and rapid growth of other microorganisms. Current antimicrobial strategies often fail due to poor diagnosis of key pathogens in biofilms. The study aims to develop anti-bacterial human antibodies in vitro from patients who had recently undergone a systemic infection by pathogenic bacteria and to use these antibodies as a tool for detecting bacteria in biofilms. Lymphocytes were separated from whole blood of patients (n = 10) and stimulated with heat-killed bacteria to produce antibodies in vitro. The specificity of antibodies in recognizing the bacteria against which they were directed was evaluated by surface plasmon resonance system (SPR) and electron microscopy. The ulcer secretions from patients with chronic and acute leg ulcers and healthy controls were analyzed by the SPR system and the results were compared with culture studies. The produced antibodies recognized bacteria with high sensitivity (SPR). The antibodies against Enterococcus fecalis bound specifically to the microorganism in a bacterial co-culture that was visualized by electron microscopy. In the present work, a method for producing specific antibodies against bacteria is introduced to recognize bacterial components in body fluids of patients suffering from pathogenic biofilms. This diagnostic technique may be most useful in clinical microbiology and in the choice of antibiotics in the treatment of serious infections.

  3. Diminished neutrophil extracellular trap (NET) formation is a novel innate immune deficiency induced by acute ethanol exposure in polymicrobial sepsis, which can be rescued by CXCL1.

    PubMed

    Jin, Liliang; Batra, Sanjay; Jeyaseelan, Samithamby

    2017-09-18

    Polymicrobial sepsis is the result of an exaggerated host immune response to bacterial pathogens. Animal models and human studies demonstrate that acute alcohol intoxication is a key risk factor for sepsis-induced mortality. Multiple chemokines, such as CXCL1, CXCL2 and CXCL5 are critical for neutrophil recruitment and proper function of neutrophils. However, it is not quite clear the mechanisms by which acute alcohol suppresses immune responses and whether alcohol-induced immunosuppression can be rescued by chemokines. Thus, we assessed whether acute ethanol challenge via gavage diminishes antibacterial host defense in a sepsis model using cecal ligation and puncture (CLP) and whether this immunosuppression can be rescued by exogenous CXCL1. We found acute alcohol intoxication augments mortality and enhances bacterial growth in mice following CLP. Ethanol exposure impairs critical antibacterial functions of mouse and human neutrophils including reactive oxygen species production, neutrophil extracellular trap (NET) formation, and NET-mediated killing in response to both Gram-negative (E. coli) and Gram-positive (Staphylococcus aureus) pathogens. As compared with WT (C57Bl/6) mice, CXCL1 knockout mice display early mortality following acute alcohol exposure followed by CLP. Recombinant CXCL1 (rCXCL1) in acute alcohol challenged CLP mice increases survival, enhances bacterial clearance, improves neutrophil recruitment, and enhances NET formation (NETosis). Recombinant CXCL1 (rCXCL1) administration also augments bacterial killing by alcohol-treated and E. coli- and S. aureus-infected neutrophils. Taken together, our data unveils novel mechanisms underlying acute alcohol-induced dysregulation of the immune responses in polymicrobial sepsis, and CXCL1 is a critical mediator to rescue alcohol-induced immune dysregulation in polymicrobial sepsis.

  4. Fungal β-1,3-glucan increases ofloxacin tolerance of Escherichia coli in a polymicrobial E. coli/Candida albicans biofilm.

    PubMed

    De Brucker, Katrijn; Tan, Yulong; Vints, Katlijn; De Cremer, Kaat; Braem, Annabel; Verstraeten, Natalie; Michiels, Jan; Vleugels, Jef; Cammue, Bruno P A; Thevissen, Karin

    2015-01-01

    In the past, biofilm-related research has focused mainly on axenic biofilms. However, in nature, biofilms are often composed of multiple species, and the resulting polymicrobial interactions influence industrially and clinically relevant outcomes such as performance and drug resistance. In this study, we show that Escherichia coli does not affect Candida albicans tolerance to amphotericin or caspofungin in an E. coli/C. albicans biofilm. In contrast, ofloxacin tolerance of E. coli is significantly increased in a polymicrobial E. coli/C. albicans biofilm compared to its tolerance in an axenic E. coli biofilm. The increased ofloxacin tolerance of E. coli is mainly biofilm specific, as ofloxacin tolerance of E. coli is less pronounced in polymicrobial E. coli/C. albicans planktonic cultures. Moreover, we found that ofloxacin tolerance of E. coli decreased significantly when E. coli/C. albicans biofilms were treated with matrix-degrading enzymes such as the β-1,3-glucan-degrading enzyme lyticase. In line with a role for β-1,3-glucan in mediating ofloxacin tolerance of E. coli in a biofilm, we found that ofloxacin tolerance of E. coli increased even more in E. coli/C. albicans biofilms consisting of a high-β-1,3-glucan-producing C. albicans mutant. In addition, exogenous addition of laminarin, a polysaccharide composed mainly of poly-β-1,3-glucan, to an E. coli biofilm also resulted in increased ofloxacin tolerance. All these data indicate that β-1,3-glucan from C. albicans increases ofloxacin tolerance of E. coli in an E. coli/C. albicans biofilm.

  5. Synergistic Effects of Honey and Propolis toward Drug Multi-Resistant Staphylococcus Aureus, Escherichia Coli and Candida Albicans Isolates in Single and Polymicrobial Cultures

    PubMed Central

    AL-Waili, Noori; Al-Ghamdi, Ahmad; Ansari, Mohammad Javed; Al-Attal, Y.; Salom, Khelod

    2012-01-01

    Background: Propolis and honey are natural bee products with wide range of biological and medicinal properties. The study investigated antimicrobial activity of ethyl alcohol extraction of propolis collected from Saudi Arabia (EEPS) and from Egypt (EEPE), and their synergistic effect when used with honey. Single and polymicrobial cultures of antibiotic resistant human pathogens were tested. Material and methods; Staphylococcus aureus (S. aureus),), Escherichia coli (E. coli) and Candida albicans (C.albicans) were cultured in 10-100% (v/v) honey diluted in broth, or 0.08-1.0% (weight/volume) EEPS and EEPE diluted in broth. Four types of polymicrobial cultures were prepared by culturing the isolates with each other in broth (control) and broth containing various concentrations of honey or propolis. Microbial growth was assessed on solid plate media after 24 h incubation. Results; EEPS and EEPE inhibited antibiotic resistant E.coli, and S.aureus, and C.albicans in single and polymicrobial cultures. S.aureus became more susceptible when it was cultured with E.coli or C.albicans or when all cultured together. C.albicans became more susceptible when it was cultured with S.aureus or with E.coli and S. aureus together. The presence of ethyl alcohol or honey potentiated antimicrobial effect of propolis toward entire microbes tested in single or polymicrobial cultures. EEPS had lower MIC toward E.coli and C.albicans than EEPE. When propolis was mixed with honey, EEPS showed lower MIC than EEPE. In addition, honey showed lower MIC toward entire microbes when mixed with EEPS than when it was mixed with EEPE. Conclusion; 1) propolis prevents the growth of the microorganisms in single and mixed microbial cultures, and has synergistic effect when used with honey or ethyl alcohol, 2) the antimicrobial property of propolis varies with geographical origin, and 3) this study will pave the way to isolate active ingredients from honey and propolis to be further tested individually or

  6. Identification of Dietzia spp. from Cardiac Tissue by 16S rRNA PCR in a Patient with Culture-Negative Device-Associated Endocarditis: A Case Report and Review of the Literature

    PubMed Central

    Wang, Guiqing; Nadelman, Robert B.

    2016-01-01

    The genus Dietzia was recently distinguished from other actinomycetes such as Rhodococcus. While these organisms are known to be distributed widely in the environment, over the past decade several novel species have been described and isolated from human clinical specimens. Here we describe the identification of Dietzia natronolimnaea/D. cercidiphylli by PCR amplification and sequencing of the 16S rRNA encoding gene from cardiac tissue in a patient with culture-negative device-associated endocarditis. PMID:28101387

  7. Biogeochemical forces shape the composition and physiology of polymicrobial communities in the cystic fibrosis lung.

    PubMed

    Quinn, Robert A; Lim, Yan Wei; Maughan, Heather; Conrad, Douglas; Rohwer, Forest; Whiteson, Katrine L

    2014-03-18

    The cystic fibrosis (CF) lung contains thick mucus colonized by opportunistic pathogens which adapt to the CF lung environment over decades. The difficulty associated with sampling airways has impeded a thorough examination of the biochemical microhabitats these pathogens are exposed to. An indirect approach is to study the responses of microbial communities to these microhabitats, facilitated by high-throughput sequencing of microbial DNA and RNA from sputum samples. Microbial metagenomes and metatranscriptomes were sequenced from multiple CF patients, and the reads were assigned taxonomy and function through sequence homology to NCBI and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database hierarchies. For a comparison, saliva microbial metagenomes from the Human Microbiome Project (HMP) were also analyzed. These analyses identified that functions encoded and expressed by CF microbes were significantly enriched for amino acid catabolism, folate biosynthesis, and lipoic acid biosynthesis. The data indicate that the community uses oxidative phosphorylation as a major energy source but that terminal electron acceptors were diverse. Nitrate reduction was the most abundant anaerobic respiratory pathway, and genes for nitrate reductase were largely assigned to Pseudomonas and Rothia. Although many reductive pathways of the nitrogen cycle were present, the cycle was incomplete, because the oxidative pathways were absent. Due to the abundant amino acid catabolism and incomplete nitrogen cycle, the CF microbial community appears to accumulate ammonia. This finding was verified experimentally using a CF bronchiole culture model system. The data also revealed abundant sensing and transport of iron, ammonium, zinc, and other metals along with a low-oxygen environment. This study reveals the core biochemistry and physiology of the CF microbiome. IMPORTANCE The cystic fibrosis (CF) microbial community is complex and adapts to the environmental conditions of the lung

  8. Development of a new pentaplex real-time PCR assay for the identification of poly-microbial specimens containing Staphylococcus aureus and other staphylococci, with simultaneous detection of staphylococcal virulence and methicillin resistance markers.

    PubMed

    Okolie, Charles E; Wooldridge, Karl G; Turner, David P; Cockayne, Alan; James, Richard

    2015-06-01

    Staphylococcus aureus strains harbouring genes encoding virulence and antibiotic resistance are of public health importance. In clinical samples, pathogenic S. aureus is often mixed with putatively less pathogenic coagulase-negative staphylococci (CoNS), both of which can harbour mecA, the gene encoding staphylococcal methicillin-resistance. There have been previous attempts at distinguishing MRSA from MRCoNS, most of which were based on the detection of one of the pathognomonic markers of S. aureus, such as coa, nuc or spa. That approach might suffice for discrete colonies and mono-microbial samples; it is inadequate for identification of clinical specimens containing mixtures of S. aureus and CoNS. In the present study, a real-time pentaplex PCR assay has been developed which simultaneously detects markers for bacteria (16S rRNA), coagulase-negative staphylococcus (cns), S. aureus (spa), Panton-Valentine leukocidin (pvl) and methicillin resistance (mecA). Staphylococcal and non-staphylococcal bacterial strains (n = 283) were used to validate the new assay. The applicability of this test to clinical samples was evaluated using spiked blood cultures (n = 43) containing S. aureus and CoNS in mono-microbial and poly-microbial models, which showed that the 5 markers were all detected as expected. Cycling completes within 1 h, delivering 100% specificity, NPV and PPV with a detection limit of 1.0 × 10(1) to 3.0 × 10(1) colony forming units (CFU)/ml, suggesting direct applicability in routine diagnostic microbiology. This is the most multiplexed real-time PCR-based PVL-MRSA assay and the first detection of a unique marker for CoNS without recourse to the conventional elimination approach. There was no evidence that this new assay produced invalid/indeterminate test results.

  9. Celecoxib Enhances the Efficacy of Low-Dose Antibiotic Treatment against Polymicrobial Sepsis in Mice and Clinical Isolates of ESKAPE Pathogens

    PubMed Central

    Annamanedi, Madhavi; Varma, Gajapati Y. N.; Anuradha, K.; Kalle, Arunasree M.

    2017-01-01

    Treatment of multidrug resistant bacterial infections has been a great challenge globally. Previous studies including our study have highlighted the use of celecoxib, a non-steroidal anti-inflammatory drug in combination with antibiotic has decreased the minimal inhibitory concentration to limit Staphylococcus aureus infection. However, the efficacy of this combinatorial treatment against various pathogenic bacteria is not determined. Therefore, we have evaluated the potential use of celecoxib in combination with low doses of antibiotic in limiting Gram-positive and Gram-negative bacteria in vivo in murine polymicrobial sepsis developed by cecum ligation and puncture (CLP) method and against clinically isolated human ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). The in vivo results clearly demonstrated a significant reduction in the bacterial load in different organs and in the inflammatory markers such as COX-2 and NF-κB via activation of SIRT1 in mice treated with imipenem, a choice of antibiotic for polymicrobial sepsis treatment. Combinatorial treatment of ampicillin and celecoxib was effective on clinical isolates of ESKAPE pathogens, 45% of tested clinical isolates showed more than 50% reduction in the colony forming units when compared to ampicillin alone. In conclusion, this non-traditional treatment strategy might be effective in clinic to reduce the dose of antibiotic to treat drug-resistant bacterial infections. PMID:28533769

  10. Celecoxib Enhances the Efficacy of Low-Dose Antibiotic Treatment against Polymicrobial Sepsis in Mice and Clinical Isolates of ESKAPE Pathogens.

    PubMed

    Annamanedi, Madhavi; Varma, Gajapati Y N; Anuradha, K; Kalle, Arunasree M

    2017-01-01

    Treatment of multidrug resistant bacterial infections has been a great challenge globally. Previous studies including our study have highlighted the use of celecoxib, a non-steroidal anti-inflammatory drug in combination with antibiotic has decreased the minimal inhibitory concentration to limit Staphylococcus aureus infection. However, the efficacy of this combinatorial treatment against various pathogenic bacteria is not determined. Therefore, we have evaluated the potential use of celecoxib in combination with low doses of antibiotic in limiting Gram-positive and Gram-negative bacteria in vivo in murine polymicrobial sepsis developed by cecum ligation and puncture (CLP) method and against clinically isolated human ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species). The in vivo results clearly demonstrated a significant reduction in the bacterial load in different organs and in the inflammatory markers such as COX-2 and NF-κB via activation of SIRT1 in mice treated with imipenem, a choice of antibiotic for polymicrobial sepsis treatment. Combinatorial treatment of ampicillin and celecoxib was effective on clinical isolates of ESKAPE pathogens, 45% of tested clinical isolates showed more than 50% reduction in the colony forming units when compared to ampicillin alone. In conclusion, this non-traditional treatment strategy might be effective in clinic to reduce the dose of antibiotic to treat drug-resistant bacterial infections.

  11. Polymicrobial Amniotic Fluid Infection with Mycoplasma/Ureaplasma and Other Bacteria Induces Severe Intra-Amniotic Inflammation Associated with Poor Perinatal Prognosis in Preterm Labor.

    PubMed

    Yoneda, Noriko; Yoneda, Satoshi; Niimi, Hideki; Ueno, Tomohiro; Hayashi, Shirou; Ito, Mika; Shiozaki, Arihiro; Urushiyama, Daichi; Hata, Kenichiro; Suda, Wataru; Hattori, Masahira; Kigawa, Mika; Kitajima, Isao; Saito, Shigeru

    2016-02-01

    To study the relationship between perinatal prognosis in cases of preterm labor (PTL) and polymicrobial infection in amniotic fluid (AF) and intra-amniotic (IA) inflammation using a highly sensitive and reliable PCR-based method. To detect prokaryotes using a nested PCR-based method, eukaryote-made thermostable DNA polymerase without bacterial DNA contamination was used in combination with bacterial universal primers. We collected AF aseptically from 118 PTL cases and 50 term subjects. The prevalence of microorganisms was 33% (39/118) by PCR and only 7.6% (9/118) by culture. PTL caused by a combination of positive Mycoplasma/Ureaplasma and other bacteria had significantly higher AF IL-8 levels and a significantly shorter amniocentesis-to-delivery interval. Our newly established PCR method is useful for detecting IA microorganisms. Polymicrobial infection with Mycoplasma/Ureaplasma and other bacteria induces severe IA inflammation associated with poor perinatal prognosis in PTL. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Phosphorylation of Extracellular Signal-Regulated Kinase (ERK)-1/2 Is Associated with the Downregulation of Peroxisome Proliferator–Activated Receptor (PPAR)-γ during Polymicrobial Sepsis

    PubMed Central

    Kaplan, Jennifer M; Hake, Paul W; Denenberg, Alvin; Nowell, Marchele; Piraino, Giovanna; Zingarelli, Basilia

    2010-01-01

    Peroxisome proliferator–activated receptor (PPAR)-γ is a ligand-activated transcription factor and regulates inflammation. Posttranslational modifications regulate the function of PPARγ, potentially affecting inflammation. PPARγ contains a mitogen-activated protein kinase (MAPK) site, and phosphorylation by extracellular signal-regulated kinase (ERK)-1/2 leads to inhibition of PPARγ. This study investigated the kinetics of PPARγ expression and activation in parenchymal and immune cells in sepsis using the MAPK/ERK kinase (MEK)-1 inhibitor, an upstream kinase of ERK1/2. Adult male Sprague Dawley rats were subjected to polymicrobial sepsis by cecal ligation and puncture. Rats received intraperitoneal injection of vehicle or the MEK1 inhibitor PD98059 (5 mg/kg) 30 min before cecal ligation and puncture. Rats were euthanized at 0, 1, 3, 6 and 18 h after cecal ligation and puncture. Control animals used were animals at time 0 h. Lung, plasma and peripheral blood mononuclear cells (PBMCs) were collected for biochemical assays. In vehicle-treated rats, polymicrobial sepsis resulted in significant lung injury. In the lung and PBMCs, nuclear levels of PPARγ were decreased and associated with an increase in phosphorylated PPARγ and phosphorylated ERK1/2 levels. Treatment with the MEK1 inhibitor increased the antiinflammatory plasma adipokine adiponectin, restored PPARγ expression in PBMCs and lung, and decreased lung injury. The inflammatory effects of sepsis cause changes in PPARγ expression and activation, in part, because of phosphorylation of PPARγ by ERK1/2. This phosphorylation can be reversed by ERK1/2 inhibition, thereby improving lung injury. PMID:20809049

  13. Double blockade of CD14 and complement C5 abolishes the cytokine storm and improves morbidity and survival in polymicrobial sepsis in mice.

    PubMed

    Huber-Lang, Markus; Barratt-Due, Andreas; Pischke, Søren E; Sandanger, Øystein; Nilsson, Per H; Nunn, Miles A; Denk, Stephanie; Gaus, Wilhelm; Espevik, Terje; Mollnes, Tom E

    2014-06-01

    Sepsis and septic shock, caused by an excessive systemic host-inflammatory response, are associated with high morbidity and mortality. The complement system and TLRs provide important pattern recognition receptors initiating the cytokine storm by extensive cross-talk. We hypothesized that double blockade of complement C5 and the TLR coreceptor CD14 could improve survival of experimental polymicrobial sepsis. Mice undergoing cecal ligation and puncture (CLP)-induced sepsis were treated with neutralizing anti-CD14 Ab biG 53, complement C5 inhibitor coversin (Ornithodoros moubata C inhibitor), or a combination thereof. The inflammatory study (24-h observation) revealed statistically significant increases in 22 of 24 measured plasma biomarkers in the untreated CLP group, comprising 14 pro- and anti-inflammatory cytokines and 8 chemokines, growth factors, and granulocyte activation markers. Single CD14 or C5 blockade significantly inhibited 20 and 19 of the 22 biomarkers, respectively. Combined CD14 and C5 inhibition significantly reduced all 22 biomarkers (mean reduction 85%; range 54-95%) compared with the untreated CLP group. Double blockade was more potent than single treatment and was required to significantly inhibit IL-6 and CXCL1. Combined inhibition significantly reduced morbidity (motility and eyelid movement) and mortality measured over 10 d. In the positive control CLP group, median survival was 36 h (range 24-48 h). Combined treatment increased median survival to 96 h (range 24-240 h) (p = 0.001), whereas survival in the single-treatment groups was not significantly increased (median and range for anti-CD14 and anti-C5 treatment were 36 h [24-48 h] and 48 h [24-96 h]). Combined with standard intervention therapy, specific blockade of CD14 and C5 might represent a promising new therapeutic strategy for treatment of polymicrobial sepsis.

  14. Double Blockade of CD14 and Complement C5 Abolishes the Cytokine Storm and Improves Morbidity and Survival in Polymicrobial Sepsis in Mice

    PubMed Central

    Huber-Lang, Markus; Barratt-Due, Andreas; Pischke, Søren E.; Sandanger, Øystein; Nilsson, Per H.; Nunn, Miles A.; Denk, Stephanie; Gaus, Wilhelm; Espevik, Terje

    2014-01-01

    Sepsis and septic shock, caused by an excessive systemic host-inflammatory response, are associated with high morbidity and mortality. The complement system and TLRs provide important pattern recognition receptors initiating the cytokine storm by extensive cross-talk. We hypothesized that double blockade of complement C5 and the TLR coreceptor CD14 could improve survival of experimental polymicrobial sepsis. Mice undergoing cecal ligation and puncture (CLP)–induced sepsis were treated with neutralizing anti-CD14 Ab biG 53, complement C5 inhibitor coversin (Ornithodoros moubata C inhibitor), or a combination thereof. The inflammatory study (24-h observation) revealed statistically significant increases in 22 of 24 measured plasma biomarkers in the untreated CLP group, comprising 14 pro- and anti-inflammatory cytokines and 8 chemokines, growth factors, and granulocyte activation markers. Single CD14 or C5 blockade significantly inhibited 20 and 19 of the 22 biomarkers, respectively. Combined CD14 and C5 inhibition significantly reduced all 22 biomarkers (mean reduction 85%; range 54–95%) compared with the untreated CLP group. Double blockade was more potent than single treatment and was required to significantly inhibit IL-6 and CXCL1. Combined inhibition significantly reduced morbidity (motility and eyelid movement) and mortality measured over 10 d. In the positive control CLP group, median survival was 36 h (range 24–48 h). Combined treatment increased median survival to 96 h (range 24–240 h) (p = 0.001), whereas survival in the single-treatment groups was not significantly increased (median and range for anti-CD14 and anti-C5 treatment were 36 h [24–48 h] and 48 h [24–96 h]). Combined with standard intervention therapy, specific blockade of CD14 and C5 might represent a promising new therapeutic strategy for treatment of polymicrobial sepsis. PMID:24790148

  15. A "silent culture-negative" abdominal aortic mycotic aneurysm: Rapid detection of Bartonella species using PCR and high-throughput mass spectrometry.

    PubMed

    Koo, Matthew; Manalili, Sheri; Bankowski, Matthew J; Sampath, Rangarajan; Hofstadler, Steven A; Koo, Joseph

    2010-03-01

    A gram-negative, rod-shaped microorganism was detected in a 69-year-old man suffering from chronic back pain but otherwise exhibiting no signs of infection. The bacterium could not be identified using any routine diagnostic modality. A research use only application utilizing PCR and Mass Spectrometry was performed on nucleic acid extracted from the tissue sample. These studies resulted in the implication of Bartonella quintana as the underlying cause of the infection. B. quintana is not a well-known cause of an abdominal aortic mycotic aneurysm. This article will discuss the B. quintana infection, its diagnosis and treatment, and reinforce the potential of B. quintana as a possible etiology in mycotic aneurysms that show no apparent indications of infection. It will also explore the potential use of polymerase chain reaction detected by electrospray ionization mass spectrometry (PCR/ESI-MS) to help identify B. quintana in a situation where other conventional methods prove non-informative.

  16. Protective Effects of Human and Mouse Soluble Scavenger-Like CD6 Lymphocyte Receptor in a Lethal Model of Polymicrobial Sepsis

    PubMed Central

    Martínez-Florensa, Mario; Consuegra-Fernández, Marta; Aranda, Fernando; Armiger-Borràs, Noelia; Di Scala, Marianna; Carrasco, Esther; Pachón, Jerónimo; Vila, Jordi; González-Aseguinolaza, Gloria

    2016-01-01

    ABSTRACT Sepsis still constitutes an unmet clinical need, which could benefit from novel adjunctive strategies to conventional antibiotic therapy. The soluble form of the scavenger-like human CD6 lymphocyte receptor (shCD6) binds to key pathogenic components from Gram-positive and -negative bacteria and shows time- and dose-dependent efficacy in mouse models of monobacterial sepsis. The objective of the present work was to demonstrate the effectiveness of infusing mouse and human sCD6 by different systemic routes, either alone or as adjunctive therapy to gold standard antibiotics, in a lethal model of polymicrobial sepsis. To this end, C57BL/6 mice undergoing high-grade septic shock induced by cecal ligation and puncture (CLP; ≥90% lethality) were infused via the intraperitoneal (i.p.) or intravenous (i.v.) route with shCD6 at different doses and time points, either alone or in combination with imipenem/cilastatin (I/C) at a dose of 33 mg/kg of body weight every 8 h. Significantly reduced mortality and proinflammatory cytokine levels were observed by i.p. infusion of a single shCD6 dose (1.25 mg/kg) 1 h pre- or post-CLP. When using the i.v. route, mice survival was significantly extended by starting shCD6 infusion at later time points post-CLP (up to 6 h after CLP). Significant adjunctive effects on mouse survival were observed by i.p. or i.v. infusion of shCD6 in combination with i.p. I/C post-CLP. Similar results were obtained in mice expressing high sustained levels (5 to 10 μg/ml) of mouse sCD6 in serum by means of transduction with hepatotropic adeno-associated virus (AAV). Taken together, the data support the conserved antibacterial effects of human and mouse sCD6 and their use as adjunctive therapy in experimental models of complex and severe polymicrobial sepsis. PMID:27895015

  17. Protective Effects of Human and Mouse Soluble Scavenger-Like CD6 Lymphocyte Receptor in a Lethal Model of Polymicrobial Sepsis.

    PubMed

    Martínez-Florensa, Mario; Consuegra-Fernández, Marta; Aranda, Fernando; Armiger-Borràs, Noelia; Di Scala, Marianna; Carrasco, Esther; Pachón, Jerónimo; Vila, Jordi; González-Aseguinolaza, Gloria; Lozano, Francisco

    2017-01-01

    Sepsis still constitutes an unmet clinical need, which could benefit from novel adjunctive strategies to conventional antibiotic therapy. The soluble form of the scavenger-like human CD6 lymphocyte receptor (shCD6) binds to key pathogenic components from Gram-positive and -negative bacteria and shows time- and dose-dependent efficacy in mouse models of monobacterial sepsis. The objective of the present work was to demonstrate the effectiveness of infusing mouse and human sCD6 by different systemic routes, either alone or as adjunctive therapy to gold standard antibiotics, in a lethal model of polymicrobial sepsis. To this end, C57BL/6 mice undergoing high-grade septic shock induced by cecal ligation and puncture (CLP; ≥90% lethality) were infused via the intraperitoneal (i.p.) or intravenous (i.v.) route with shCD6 at different doses and time points, either alone or in combination with imipenem/cilastatin (I/C) at a dose of 33 mg/kg of body weight every 8 h. Significantly reduced mortality and proinflammatory cytokine levels were observed by i.p. infusion of a single shCD6 dose (1.25 mg/kg) 1 h pre- or post-CLP. When using the i.v. route, mice survival was significantly extended by starting shCD6 infusion at later time points post-CLP (up to 6 h after CLP). Significant adjunctive effects on mouse survival were observed by i.p. or i.v. infusion of shCD6 in combination with i.p. I/C post-CLP. Similar results were obtained in mice expressing high sustained levels (5 to 10 μg/ml) of mouse sCD6 in serum by means of transduction with hepatotropic adeno-associated virus (AAV). Taken together, the data support the conserved antibacterial effects of human and mouse sCD6 and their use as adjunctive therapy in experimental models of complex and severe polymicrobial sepsis. Copyright © 2016 American Society for Microbiology.

  18. Blood-Brain Barrier Deterioration and Hippocampal Gene Expression in Polymicrobial Sepsis: An Evaluation of Endothelial MyD88 and the Vagus Nerve.

    PubMed

    Honig, Gerard; Mader, Simone; Chen, Huiyi; Porat, Amit; Ochani, Mahendar; Wang, Ping; Volpe, Bruce T; Diamond, Betty

    2016-01-01

    Systemic infection can initiate or exacerbate central nervous system (CNS) pathology, even in the absence of overt invasion of bacteria into the CNS. Recent epidemiological studies have demonstrated that human survivors of sepsis have an increased risk of long-term neurocognitive decline. There is thus a need for improved understanding of the physiological mechanisms whereby acute sepsis affects the CNS. In particular, MyD88-dependent activation of brain microvascular endothelial cells and a resulting loss of blood-brain barrier integrity have been proposed to play an important role in the effects of systemic inflammation on the CNS. Signaling through the vagus nerve has also been considered to be an important component of CNS responses to systemic infection. Here, we demonstrate that blood-brain barrier permeabilization and hippocampal transcriptional responses during polymicrobial sepsis occur even in the absence of MyD88-dependent signaling in cerebrovascular endothelial cells. We further demonstrate that these transcriptional responses can occur without vagus nerve input. These results suggest that redundant signals mediate CNS responses in sepsis. Either endothelial or vagus nerve activation may be individually sufficient to transmit systemic inflammation to the central nervous system. Transcriptional activation in the forebrain in sepsis may be mediated by MyD88-independent endothelial mechanisms or by non-vagal neuronal pathways.

  19. Polymicrobial bacterial or fungal infections: incidence, spectrum of infection, risk factors, and clinical outcomes from a large hematopoietic stem cell transplant center.

    PubMed

    Trifilio, S; Zhou, Z; Fong, J L; Zomas, A; Liu, D; Zhao, C; Zhang, J; Mehta, J

    2015-04-01

    Infections cause significant morbidity and mortality for patients who undergo hematopoietic stem cell transplantation (HSCT). Cancer patients who develop polymicrobial infection (PI) are at increased risk for poor clinical outcomes, yet very limited data have been published within the HSCT setting. An observational study of 901 stem cell transplant recipients was conducted at Northwestern Memorial Hospital to identify the incidence, risk factors and outcomes for HSCT recipients who develop infection(s) with multiple bacterial or fungal organisms. Among 901 HSCT recipients reviewed (675 autografts and 226 allografts), 237 patients (27%) had microbiologically documented microorganisms isolated, including 179 patients (76%) with monomicrobial infection and 59 patients (24%) with multiple microorganisms, of which 34 (14%) were classified as PI, and 25 (10%) as multiple distinct episodes of infection. The results show co-infection with multiple organisms during HSCT is relatively rare; however, these patients are at an increased risk for the development of acute graft-versus-host disease, delayed engraftment, and overall mortality. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Evaluation of a novel PCR-based diagnostic assay for detection of Mycobacterium tuberculosis in sputum samples.

    PubMed Central

    Maher, M; Glennon, M; Martinazzo, G; Turchetti, E; Marcolini, S; Smith, T; Dawson, M T

    1996-01-01

    We report on a PCR-based assay we have developed for the detection of Mycobacterium tuberculosis in sputum samples. One hundred sputum specimens, which included 34 culture-positive and 66 culture-negative specimens, were evaluated with this system. Of the 34 culture-positive specimens, 31 were PCR positive, and 60 of the culture-negative specimens were PCR negative. An internal standard has been included in the assay system to monitor PCR inhibition and to confirm the reliability of the PCR assay. PMID:8862607

  1. Administration of antibiotic agents before intraoperative sampling in orthopedic infections alters culture results.

    PubMed

    Al-Mayahi, Mohamed; Cian, Anais; Lipsky, Benjamin A; Suvà, Domizio; Müller, Camillo; Landelle, Caroline; Miozzari, Hermès H; Uçkay, Ilker

    2015-11-01

    Many physicians and surgeons think that prescribing antibiotics before intraoperative sampling does not alter the microbiological results. Case-control study of adult patients hospitalized with orthopedic infections. Among 2740 episodes of orthopedic infections, 1167 (43%) had received antibiotic therapy before surgical sampling. Among these, 220 (19%) grew no pathogens while the proportion of culture-negative results in the 2573 who had no preoperative antibiotic therapy was only 6%. By multivariate analyses, pre-operative antibiotic exposure was associated with significantly more culture-negative results (odds ratio 2.8, 95% confidence interval 2.1-3.7), more non-fermenting rods and skin commensals (odds ratio 2.8 and 3.0, respectively). Even a single pre-operative dose of antibiotic was significantly associated with subsequent culture-negative results (19/93 vs. 297/2350; χ²-test, p = 0.01) and skin commensals (17/74 vs. 274/2350; p = 0.01) compared to episodes without preceding prophylaxis. Prior antibiotic use, including single-dose prophylactic administrations, is three-fold associated with culture-negative results, non-fermenting rods and resistant skin commensals. Copyright © 2015 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  2. Antibacterial Action of a Condensed Tannin Extracted from Astringent Persimmon as a Component of Food Addictive Pancil PS-M on Oral Polymicrobial Biofilms

    PubMed Central

    Tomiyama, Kiyoshi; Mukai, Yoshiharu; Saito, Masahiro; Watanabe, Kiyoko; Kumada, Hidefumi; Nihei, Tomotaro; Hamada, Nobushiro; Teranaka, Toshio

    2016-01-01

    The purpose of this study was to evaluate the antibacterial activity against polymicrobial (PM) biofilms of a condensed tannin extracted from astringent persimmon (PS-M), which is contained in refreshing beverages commercially available in Japan. Salivary PM biofilms were formed anaerobically on glass coverslips for 24 and 72 h and were treated for 5 min with sterilized deionized water (DW), 0.05 and 0.2 wt% chlorhexidine digluconate (CHX), and 0.5–4.0 wt% PS-M solution. The colony forming units (CFU/mL) were determined and morphological changes of the biofilms were observed by scanning electron microscopy (SEM). The CFUs were lower in all PS-M and CHX groups compared to the DW group. PS-M exerted a dose-dependent effect. PS-M (1.53 × 107) at a dose of 4.0 wt% had the same effect as 0.2 wt% CHX (2.03 × 107), regardless of the culture period. SEM revealed the biofilm structures were considerably destroyed in the 4.0 wt% PS-M and 0.2 wt% CHX. These findings indicate that the antibacterial effects of PS-M, a naturally derived substance, are comparable to those of CHX. PS-M may keep the oral cavity clean and prevent dental caries and periodontal disease related to dental plaque, as well as systemic disease such as aspiration pneumonitis. PMID:26981533

  3. Antibacterial Action of a Condensed Tannin Extracted from Astringent Persimmon as a Component of Food Addictive Pancil PS-M on Oral Polymicrobial Biofilms.

    PubMed

    Tomiyama, Kiyoshi; Mukai, Yoshiharu; Saito, Masahiro; Watanabe, Kiyoko; Kumada, Hidefumi; Nihei, Tomotaro; Hamada, Nobushiro; Teranaka, Toshio

    2016-01-01

    The purpose of this study was to evaluate the antibacterial activity against polymicrobial (PM) biofilms of a condensed tannin extracted from astringent persimmon (PS-M), which is contained in refreshing beverages commercially available in Japan. Salivary PM biofilms were formed anaerobically on glass coverslips for 24 and 72 h and were treated for 5 min with sterilized deionized water (DW), 0.05 and 0.2 wt% chlorhexidine digluconate (CHX), and 0.5-4.0 wt% PS-M solution. The colony forming units (CFU/mL) were determined and morphological changes of the biofilms were observed by scanning electron microscopy (SEM). The CFUs were lower in all PS-M and CHX groups compared to the DW group. PS-M exerted a dose-dependent effect. PS-M (1.53 × 10(7)) at a dose of 4.0 wt% had the same effect as 0.2 wt% CHX (2.03 × 10(7)), regardless of the culture period. SEM revealed the biofilm structures were considerably destroyed in the 4.0 wt% PS-M and 0.2 wt% CHX. These findings indicate that the antibacterial effects of PS-M, a naturally derived substance, are comparable to those of CHX. PS-M may keep the oral cavity clean and prevent dental caries and periodontal disease related to dental plaque, as well as systemic disease such as aspiration pneumonitis.

  4. Insights into Cystic Fibrosis Polymicrobial Consortia: The Role of Species Interactions in Biofilm Development, Phenotype, and Response to In-Use Antibiotics.

    PubMed

    Magalhães, Andreia P; Lopes, Susana P; Pereira, Maria O

    2016-01-01

    Cystic Fibrosis (CF) airways disease involves complex polymicrobial infections where different bacterial species can interact and influence each other and/or even interfere with the whole community. To gain insights into the role that interactions between Pseudomonas aeruginosa in co-culture with Staphylococcus aureus, Inquilinus limosus, and Stenotrophomonas maltophilia may play in infection, the reciprocal effect during biofilm formation and the response of dual biofilms toward ciprofloxacin under in vitro atmospheres with different oxygen availabilities were evaluated. Biofilm formation kinetics showed that the growth of S. aureus, I. limosus, and S. maltophilia was disturbed in the presence of P. aeruginosa, under both aerobic and anaerobic environments. On the other hand, under aerobic conditions, I. limosus led to a decrease in biofilm mass production by P. aeruginosa, although biofilm-cells viability remains unaltered. The interaction between S. maltophilia and P. aeruginosa positively influenced dual biofilm development by increasing its biomass. Compared with monocultures, biomass of P. aeruginosa+ S. aureus biofilms was significantly reduced by reciprocal interference. When grown in dual biofilms with P. aeruginosa, ciprofloxacin was less effective against S. aureus, I. limosus, and S. maltophilia, with increasing antibiotic doses leading to drastic inhibitions of P. aeruginosa cultivability. Therefore, P. aeruginosa might be responsible for the protection of the whole dual consortia against ciprofloxacin activity. Based on the overall data, it can be speculated that reciprocal interferences occur between the different bacterial species in CF lung, regardless the level of oxygen. The findings also suggest that alterations of bacterial behavior due to species interplay may be important for disease progression in CF infection.

  5. Insights into Cystic Fibrosis Polymicrobial Consortia: The Role of Species Interactions in Biofilm Development, Phenotype, and Response to In-Use Antibiotics

    PubMed Central

    Magalhães, Andreia P.; Lopes, Susana P.; Pereira, Maria O.

    2017-01-01

    Cystic Fibrosis (CF) airways disease involves complex polymicrobial infections where different bacterial species can interact and influence each other and/or even interfere with the whole community. To gain insights into the role that interactions between Pseudomonas aeruginosa in co-culture with Staphylococcus aureus, Inquilinus limosus, and Stenotrophomonas maltophilia may play in infection, the reciprocal effect during biofilm formation and the response of dual biofilms toward ciprofloxacin under in vitro atmospheres with different oxygen availabilities were evaluated. Biofilm formation kinetics showed that the growth of S. aureus, I. limosus, and S. maltophilia was disturbed in the presence of P. aeruginosa, under both aerobic and anaerobic environments. On the other hand, under aerobic conditions, I. limosus led to a decrease in biofilm mass production by P. aeruginosa, although biofilm-cells viability remains unaltered. The interaction between S. maltophilia and P. aeruginosa positively influenced dual biofilm development by increasing its biomass. Compared with monocultures, biomass of P. aeruginosa+ S. aureus biofilms was significantly reduced by reciprocal interference. When grown in dual biofilms with P. aeruginosa, ciprofloxacin was less effective against S. aureus, I. limosus, and S. maltophilia, with increasing antibiotic doses leading to drastic inhibitions of P. aeruginosa cultivability. Therefore, P. aeruginosa might be responsible for the protection of the whole dual consortia against ciprofloxacin activity. Based on the overall data, it can be speculated that reciprocal interferences occur between the different bacterial species in CF lung, regardless the level of oxygen. The findings also suggest that alterations of bacterial behavior due to species interplay may be important for disease progression in CF infection. PMID:28133457

  6. Synthesized zinc peroxide nanoparticles (ZnO2-NPs): a novel antimicrobial, anti-elastase, anti-keratinase, and anti-inflammatory approach toward polymicrobial burn wounds.

    PubMed

    Ali, Sameh Samir; Morsy, Reda; El-Zawawy, Nessma Ahmed; Fareed, Mervat F; Bedaiwy, Mohamed Yaser

    2017-01-01

    Increasing of multidrug resistance (MDR) remains an intractable challenge for burn patients. Innovative nanomaterials are also in high demand for the development of new antimicrobial biomaterials that inevitably have opened new therapeutic horizons in medical approaches and lead to many efforts for synthesizing new metal oxide nanoparticles (NPs) for better control of the MDR associated with the polymicrobial burn wounds. Recently, it seems that metal oxides can truly be considered as highly efficient inorganic agents with antimicrobial properties. In this study, zinc peroxide NPs (ZnO2-NPs) were synthesized using the co-precipitation method. Synthesized ZnO2-NPs were characterized by X-ray diffraction, Fourier transformed infrared, transmission electron microscopy, thermogravimetric analysis, differential scanning calorimetry, and ultraviolet-visible spectroscopy. The characterization techniques revealed synthesis of the pure phase of non-agglomerated ZnO2-NPs having sizes in the range of 15-25 nm with a transition temperature of 211°C. Antimicrobial activity of ZnO2-NPs was determined against MDR Pseudomonas aeruginosa (PA) and Aspergillus niger (AN) strains isolated from burn wound infections. Both strains, PA6 and AN4, were found to be more susceptible strains to ZnO2-NPs. In addition, a significant decrease in elastase and keratinase activities was recorded with increased concentrations of ZnO2-NPs until 200 µg/mL. ZnO2-NPs revealed a significant anti-inflammatory activity against PA6 and AN4 strains as demonstrated by membrane stabilization, albumin denaturation, and proteinase inhibition. Moreover, the results of in vivo histopathology assessment confirmed the potential role of ZnO2-NPs in the improvement of skin wound healing in the experimental animal models. Clearly, the synthesized ZnO2-NPs have demonstrated a competitive capability as antimicrobial, anti-elastase, anti-keratinase, and anti-inflammatory candidates, suggesting that the ZnO2-NPs are

  7. Elevated Expression of IL-23/IL-17 Pathway-Related Mediators Correlates with Exacerbation of Pulmonary Inflammation During Polymicrobial Sepsis1

    PubMed Central

    Cauvi, David M.; Williams, Michael R.; Bermudez, Jose A.; Armijo, Gabrielle; De Maio, Antonio

    2014-01-01

    Sepsis is a leading cause of death in the United States, claiming more than 215,000 lives every year. A primary condition observed in septic patients is the incidence of acute respiratory distress syndrome (ARDS), which is characterized by the infiltration of neutrophils into the lung. Prior studies have shown differences in pulmonary neutrophil accumulation in C57BL/6J (B6) and A/J mice after endotoxic and septic shock. However, the mechanism by which neutrophils accumulate in the lung after polymicrobial sepsis induced by cecal ligation and puncture (CLP) still remains to be fully elucidated. We show in this study that lung inflammation, characterized by neutrophil infiltration and expression of inflammatory cytokines, was aggravated in B6 as compared to A/J mice and correlated with high expression of p19, the IL-23-specific subunit. Furthermore, LPS stimulation of B6- and A/J-derived macrophages, one of the main producers of IL-23 and IL-12, revealed that B6 mice favored the production of IL-23 whereas A/J-derived macrophages expressed higher levels of IL-12. In addition, expression of IL-17, known to be upregulated by IL-23, was also more elevated in the lung of B6 mice when compared to A/J mice. In contrast, pulmonary expression of IFN-γ was much more pronounced in A/J than in B6 mice, which was most likely a result of a higher production of IL-12. The expression of the IL-17-dependent neutrophil recruitment factors CXCL2 and G-CSF was also higher in B6 mice. Altogether, these results suggest that increased activation of the IL-23/IL-17 pathway has detrimental effects on sepsis-induced lung inflammation, whereas activation of the IL-12/IFN-γ pathway may lead, in contrast, to less pronounced inflammatory events. These two pathways may become possible therapeutic targets for the treatment of sepsis-induced ARDS. PMID:24978886

  8. Animal models of polymicrobial pneumonia

    PubMed Central

    Hraiech, Sami; Papazian, Laurent; Rolain, Jean-Marc; Bregeon, Fabienne

    2015-01-01

    Pneumonia is one of the leading causes of severe and occasionally life-threatening infections. The physiopathology of pneumonia has been extensively studied, providing information for the development of new treatments for this condition. In addition to in vitro research, animal models have been largely used in the field of pneumonia. Several models have been described and have provided a better understanding of pneumonia under different settings and with various pathogens. However, the concept of one pathogen leading to one infection has been challenged, and recent flu epidemics suggest that some pathogens exhibit highly virulent potential. Although “two hits” animal models have been used to study infectious diseases, few of these models have been described in pneumonia. Therefore the aims of this review were to provide an overview of the available literature in this field, to describe well-studied and uncommon pathogen associations, and to summarize the major insights obtained from this information. PMID:26170617

  9. Polymicrobial ventriculitis involving Pseudomonas fulva.

    PubMed

    Rebolledo, Paulina A; Vu, Catphuong Cathy L; Carlson, Renee Donahue; Kraft, Colleen S; Anderson, Evan J; Burd, Eileen M

    2014-06-01

    Infections due to Pseudomonas fulva remain a rare but emerging concern. A case of ventriculitis due to Enterobacter cloacae and Pseudomonas fulva following placement of an external ventricular drain is described. Similar to other reports, the organism was initially misidentified as Pseudomonas putida. The infection was successfully treated with levofloxacin.

  10. Performance of selective and differential media in the primary isolation of yeasts from different biological samples.

    PubMed

    Silva, Jaqueline Otero; Franceschini, Silvio Antônio; Lavrador, Marco Aurélio Sicchiroli; Candido, Regina Célia

    2004-01-01

    In view of the increase in yeast infections, especially polymicrobial ones, differential culture media have acquired increasing importance. The present study evaluated the Sabouraud chloramphenicol, Biggy agar, Pagano Levin agar and CHROMagar Candida media in terms of isolation, number of yeast colony forming units per plate, and inhibition of bacteria and filamentous fungi. To this end, we used 223 biological samples, including feces, and oral, vaginal and anal mucosae from 86 patients presenting or not symptoms of fungal infections. The four media did not differ significantly in terms of detection of yeast-positive cultures. The number of colony forming units per plate ranged from zero to 2.380, with a predominance of counts of 1 to 9 colonies per plate. No significant differences were observed among the four culture media in terms of number of colonies counted, for each kind of biological material. Fifteen species belonging to the genera Candida, Saccharomyces, Cryptococcus, Trichosporon and Rhodotorula were isolated, with C. albicans being the predominant species, followed by C. parapsilosis and R. rubra. CHROMagar Candida and Biggy agar were complementary in the isolation of the different species and favored a greater recovery of polymicrobial cultures. Pagano Levin agar isolated the smallest variety of species. Sabouraud chloramphenicol agar was the least effective in terms of bacterial inhibition and favored a greater development of filamentous fungi. The results suggest that more than one culture medium should be used for an adequate primary isolation.

  11. Evaluation of direct E-test on lower respiratory tract samples: a rapid and accurate procedure for antimicrobial susceptibility testing.

    PubMed

    Cercenado, Emilia; Cercenado, Sonia; Marín, Mercedes; Rico, María-Victoria; Vicente, Teresa; Bouza, Emilio

    2007-06-01

    We compared the direct E-test susceptibility testing (DET) on respiratory samples with a standard microbroth dilution method (MBD) after quantitative cultures. A total of 152 samples from intensive care unit patients were processed by DET onto Mueller-Hinton agar. Oxacillin, piperacillin/tazobactam, cefepime, imipenem, ciprofloxacin, and amikacin were the antimicrobials evaluated. Cultures were 102 monomicrobials and 50 polymicrobials. Overall, 93.8% of the isolates were recovered by the DET. Among the 772 microorganism-antibiotic combinations evaluated, there was a total agreement with the MBD in 96.1%. There were 8 very major errors (1.03%), 15 major (1.94%), and 7 minor (0.91%). All discrepancies but one corresponded to polymicrobial cultures, and most occurred with cefepime (8 cases, 7.07%) and imipenem (7 cases, 6.18%). Readings of DET were easy to interpret and improved with transmitted light. DET on respiratory samples is a rapid technique that provides susceptibility results in 18 to 24 h comparable with these obtained by MBD.

  12. Sample Design.

    ERIC Educational Resources Information Center

    Ross, Kenneth N.

    1987-01-01

    This article considers various kinds of probability and non-probability samples in both experimental and survey studies. Throughout, how a sample is chosen is stressed. Size alone is not the determining consideration in sample selection. Good samples do not occur by accident; they are the result of a careful design. (Author/JAZ)

  13. Identification of legionella in clinical samples.

    PubMed

    Jarraud, Sophie; Descours, Ghislaine; Ginevra, Christophe; Lina, Gerard; Etienne, Jerome

    2013-01-01

    Currently, several methods are used for the detection of Legionella in clinical samples, and these methods constitute part of the criteria for defining legionellosis cases. Urinary antigen detection is the first-line diagnostic test, although this test is limited to L. pneumophila serogroup 1 (Lp1) (Helbig et al., J Clin Microbiol 41:838-840, 2003). The use of molecular techniques can improve Legionaire's disease (LD) diagnosis by detecting other serogroups and species (Diederen et al., J Clin Microbiol 46:671-677, 2008). The isolation of Legionella strains from pulmonary samples by axenic culture is still required to perform further epidemiological investigations (Blyth et al., N S W Public Health Bull 20:157-161, 2009; Fields et al., Clin Microbiol Rev 15:506-526, 2002) but demonstrates various sensitivities. Amoebic coculture has been described as a method to recover Legionella from clinical culture-negative specimens (La Scola et al., J Clin Microbiol 39:365-366, 2001; Rowbotham, J Clin Pathol 36:978-986, 1983) and can be proposed for optimizing Legionella strain isolation from samples contaminated by oropharyngeal flora. Identification of Legionella isolates is based on serological characterization, genotypic methods (with sequencing of the mip gene as the standard method) and, more recently, the Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) method.This chapter is limited to the identification of Legionella in clinical samples; antibody detection in human serum will not be discussed.

  14. Capillary sample

    MedlinePlus

    ... using capillary blood sampling. Disadvantages to capillary blood sampling include: Only a limited amount of blood can be drawn using this method. The procedure has some risks (see below). Capillary ...

  15. Laser sampling

    NASA Astrophysics Data System (ADS)

    Gorbatenko, A. A.; Revina, E. I.

    2015-10-01

    The review is devoted to the major advances in laser sampling. The advantages and drawbacks of the technique are considered. Specific features of combinations of laser sampling with various instrumental analytical methods, primarily inductively coupled plasma mass spectrometry, are discussed. Examples of practical implementation of hybrid methods involving laser sampling as well as corresponding analytical characteristics are presented. The bibliography includes 78 references.

  16. Nocardia isolation from clinical samples with the paraffin baiting technique

    PubMed Central

    Bafghi, Mehdi Fatahi; Heidarieh, Parvin; Soori, Tahereh; Saber, Sasan; Meysamie, Alipasha; Gheitoli, Khavar; Habibnia, Shadi; Rasouli Nasab, Masoumeh; Eshraghi, Seyyed Saeed

    2015-01-01

    Background The genus Nocardia is a cause of infection in the lungs, skin, brain, cerebrospinal fluid, eyes, joints and kidneys. Nocardia isolation from polymicrobial specimens is difficult due to its slow growth. Several methods have been reported for Nocardia isolation from clinical samples. In the current study, we used three methods: paraffin baiting technique, paraffin agar, and conventional media for Nocardia isolation from various clinical specimens from Iranian patients. Methods In this study, we examined 517 samples from various clinical specimens such as: sputum of patients with suspected tuberculosis, bronchoalveolar lavage, sputum of patients with cystic fibrosis, tracheal aspirate, cutaneous and subcutaneous abscesses, cerebrospinal fluid, dental abscess, mycetoma, wound, bone marrow biopsy, and gastric lavage. All collected specimens were cultured on carbon-free broth tubes (paraffin baiting technique), paraffin agar, Sabouraud dextrose agar, and Sabouraud dextrose agar with cycloheximide and were incubated at 35°C for one month. Results Seven Nocardia spp. were isolated with paraffin baiting technique, compared with 5 positive results with the paraffin agar technique and 3 positive results with Sabouraud dextrose agar with and without cycloheximide. The prevalence of nocardial infections in our specimens was 5.28%. Conclusion In the present study, the use of the paraffin baiting technique appeared to be more effective than other methods for Nocardia isolation from various clinical specimens. PMID:25763363

  17. Lunar Sample Quarantine & Sample Curation

    NASA Technical Reports Server (NTRS)

    Allton, Judith H.

    2000-01-01

    The main goal of this presentation is to discuss some of the responsibility of the lunar sample quarantine project. The responsibilities are: flying the mission safely, and on schedule, protect the Earth from biohazard, and preserve scientific integrity of samples.

  18. Sampling Development

    PubMed Central

    Adolph, Karen E.; Robinson, Scott R.

    2011-01-01

    Research in developmental psychology requires sampling at different time points. Accurate depictions of developmental change provide a foundation for further empirical studies and theories about developmental mechanisms. However, overreliance on widely spaced sampling intervals in cross-sectional and longitudinal designs threatens the validity of the enterprise. This article discusses how to sample development in order to accurately discern the shape of developmental change. The ideal solution is daunting: to summarize behavior over 24-hour intervals and collect daily samples over the critical periods of change. We discuss the magnitude of errors due to undersampling, and the risks associated with oversampling. When daily sampling is not feasible, we offer suggestions for sampling methods that can provide preliminary reference points and provisional sketches of the general shape of a developmental trajectory. Denser sampling then can be applied strategically during periods of enhanced variability, inflections in the rate of developmental change, or in relation to key events or processes that may affect the course of change. Despite the challenges of dense repeated sampling, researchers must take seriously the problem of sampling on a developmental time scale if we are to know the true shape of developmental change. PMID:22140355

  19. Sampling Development

    ERIC Educational Resources Information Center

    Adolph, Karen E.; Robinson, Scott R.

    2011-01-01

    Research in developmental psychology requires sampling at different time points. Accurate depictions of developmental change provide a foundation for further empirical studies and theories about developmental mechanisms. However, overreliance on widely spaced sampling intervals in cross-sectional and longitudinal designs threatens the validity of…

  20. Sampling Development

    ERIC Educational Resources Information Center

    Adolph, Karen E.; Robinson, Scott R.

    2011-01-01

    Research in developmental psychology requires sampling at different time points. Accurate depictions of developmental change provide a foundation for further empirical studies and theories about developmental mechanisms. However, overreliance on widely spaced sampling intervals in cross-sectional and longitudinal designs threatens the validity of…

  1. Elevating sampling

    PubMed Central

    Labuz, Joseph M.; Takayama, Shuichi

    2014-01-01

    Sampling – the process of collecting, preparing, and introducing an appropriate volume element (voxel) into a system – is often under appreciated and pushed behind the scenes in lab-on-a-chip research. What often stands in the way between proof-of-principle demonstrations of potentially exciting technology and its broader dissemination and actual use, however, is the effectiveness of sample collection and preparation. The power of micro- and nanofluidics to improve reactions, sensing, separation, and cell culture cannot be accessed if sampling is not equally efficient and reliable. This perspective will highlight recent successes as well as assess current challenges and opportunities in this area. PMID:24781100

  2. Culture-negative ulcerative keratitis after laser in situ keratomileusis.

    PubMed

    Lam, D S; Leung, A T; Wu, J T; Fan, D S; Cheng, A C; Wang, Z

    1999-07-01

    A 40-year old man, highly myopic in both eyes, had laser in situ keratomileusis (LASIK) in the left eye in November 1996. Corneal melting and ulceration and fine striae-like interface infiltrates were noticed 1 day postoperatively. There was no response to intensive topical antibiotics in the form of hourly ofloxacin 3% (Tarivid), and satellite lesions developed on day 4. Corneal scrapings for gram stain and culture were done twice. No bacterial or fungal organisms were identified. Intensive topical fortified vancomycin (50 mg/mL) was added, and the lesions resolved gradually over the ensuing 2 weeks. Eighteen months after LASIK, refraction was -1.50 - 0.75 x 105 in the left eye, and uncorrected visual acuity was 20/70, correctable to 20/25 with spectacles.

  3. SAMPLING SYSTEM

    DOEpatents

    Hannaford, B.A.; Rosenberg, R.; Segaser, C.L.; Terry, C.L.

    1961-01-17

    An apparatus is given for the batch sampling of radioactive liquids such as slurries from a system by remote control, while providing shielding for protection of operating personnel from the harmful effects of radiation.

  4. Application of a pathogen microarray for the analysis of viruses and bacteria in clinical diagnostic samples from pigs.

    PubMed

    Jaing, Crystal J; Thissen, James B; Gardner, Shea N; McLoughlin, Kevin S; Hullinger, Pam J; Monday, Nicholas A; Niederwerder, Megan C; Rowland, Raymond R R

    2015-05-01

    Many of the disease syndromes challenging the commercial swine industry involve the analysis of complex problems caused by polymicrobial, emerging or reemerging, and transboundary pathogens. This study investigated the utility of the Lawrence Livermore Microbial Detection Array (Lawrence Livermore National Laboratory, Livermore, California), designed to detect 8,101 species of microbes, in the evaluation of known and unknown microbes in serum, oral fluid, and tonsil from pigs experimentally coinfected with Porcine reproductive and respiratory syndrome virus (PRRSV) and Porcine circovirus-2 (PCV-2). The array easily identified PRRSV and PCV-2, but at decreased sensitivities compared to standard polymerase chain reaction detection methods. The oral fluid sample was the most informative, possessing additional signatures for several swine-associated bacteria, including Streptococcus sp., Clostridium sp., and Staphylococcus sp.

  5. Magnetooptic sampling

    NASA Astrophysics Data System (ADS)

    Riordan, Jennifer Ann

    1999-10-01

    The magneto-optic sampling (MO) technique provides an alternate and complementary method for detection of freely-propagating electromagnetic pulses. With the Faraday effect as the basis for the sampling technique, coupling between the optical sampling pulses and the terahertz (THz) electromagnetic waves is simplified strict orthogonal propagation. Optimal Faraday rotation occurs when the propagation direction of the optical pulses are parallel to the magnetic component THz waves. Several materials were experimentally investigated. These materials include glasses (SF-59, Tb:glass), crystals (TGG, KTb3F10) and semiconductors (GaP, ZnTe). Several of the materials possess unknowns at the GHz and THz frequencies of interest. As such, time- domain spectroscopic experiments determined refractive index and absorption coefficient data for these samples. Theoretical descriptions and author-developed simulations are contrasted with experimental data throughout this work. A minimum temporal response of 1.3 ps followed theoretical predictions for the orthogonal propagation of the THz and probe beams in a sample of TGG. The minimum detectable magnetic field was 10-8T/ Hz , with shot-noise limited detection. Time-resolved measurements of electromagnetic pulses in liquids via MO sampling propel this technique beyond that possible with electro-optically based experiments. Both polar (water, acetone, methanol) and nonpolar (carbon tetrachloride, carbon disulfide) liquids were investigated and provided frequency bandwidth responses up to 20 GHz. The nonpolar liquids demonstrated shorter temporal responses than the polar liquids. This is attributable to the dielectric responses of the liquids, as the polar liquids have much higher absorption and dispersion at GHz frequencies. Comparisons between these liquids are developed with theoretical explanations. Direct probing of an electromagnetic pulse inside a liquid is discussed and demonstrated. Finally, a

  6. Hydrogen sulfide production from subgingival plaque samples.

    PubMed

    Basic, A; Dahlén, G

    2015-10-01

    Periodontitis is a polymicrobial anaerobe infection. Little is known about the dysbiotic microbiota and the role of bacterial metabolites in the disease process. It is suggested that the production of certain waste products in the proteolytic metabolism may work as markers for disease severity. Hydrogen sulfide (H2S) is a gas produced by degradation of proteins in the subgingival pocket. It is highly toxic and believed to have pro-inflammatory properties. We aimed to study H2S production from subgingival plaque samples in relation to disease severity in subjects with natural development of the disease, using a colorimetric method based on bismuth precipitation. In remote areas of northern Thailand, adults with poor oral hygiene habits and a natural development of periodontal disease were examined for their oral health status. H2S production was measured with the bismuth method and subgingival plaque samples were analyzed for the presence of 20 bacterial species with the checkerboard DNA-DNA hybridization technique. In total, 43 subjects were examined (age 40-60 years, mean PI 95 ± 6.6%). Fifty-six percent had moderate periodontal breakdown (CAL > 3 < 7 mm) and 35% had severe periodontal breakdown (CAL > 7 mm) on at least one site. Parvimonas micra, Filifactor alocis, Porphyromonas endodontalis and Fusobacterium nucleatum were frequently detected. H2S production could not be correlated to periodontal disease severity (PPD or CAL at sampled sites) or to a specific bacterial composition. Site 21 had statistically lower production of H2S (p = 0.02) compared to 16 and 46. Betel nut chewers had statistically significant lower H2S production (p = 0.01) than non-chewers. Rapid detection and estimation of subgingival H2S production capacity was easily and reliably tested by the colorimetric bismuth sulfide precipitation method. H2S may be a valuable clinical marker for degradation of proteins in the subgingival pocket.

  7. SAMPLING OSCILLOSCOPE

    DOEpatents

    Sugarman, R.M.

    1960-08-30

    An oscilloscope is designed for displaying transient signal waveforms having random time and amplitude distributions. The oscilloscopc is a sampling device that selects for display a portion of only those waveforms having a particular range of amplitudes. For this purpose a pulse-height analyzer is provided to screen the pulses. A variable voltage-level shifter and a time-scale rampvoltage generator take the pulse height relative to the start of the waveform. The variable voltage shifter produces a voltage level raised one step for each sequential signal waveform to be sampled and this results in an unsmeared record of input signal waveforms. Appropriate delay devices permit each sample waveform to pass its peak amplitude before the circuit selects it for display.

  8. Sampling apparatus

    DOEpatents

    Gordon, Norman R.; King, Lloyd L.; Jackson, Peter O.; Zulich, Alan W.

    1989-01-01

    A sampling apparatus is provided for sampling substances from solid surfaces. The apparatus includes first and second elongated tubular bodies which telescopically and sealingly join relative to one another. An absorbent pad is mounted to the end of a rod which is slidably received through a passageway in the end of one of the joined bodies. The rod is preferably slidably and rotatably received through the passageway, yet provides a selective fluid tight seal relative thereto. A recess is formed in the rod. When the recess and passageway are positioned to be coincident, fluid is permitted to flow through the passageway and around the rod. The pad is preferably laterally orientable relative to the rod and foldably retractable to within one of the bodies. A solvent is provided for wetting of the pad and solubilizing or suspending the material being sampled from a particular surface.

  9. Sampling apparatus

    DOEpatents

    Gordon, N.R.; King, L.L.; Jackson, P.O.; Zulich, A.W.

    1989-07-18

    A sampling apparatus is provided for sampling substances from solid surfaces. The apparatus includes first and second elongated tubular bodies which telescopically and sealingly join relative to one another. An absorbent pad is mounted to the end of a rod which is slidably received through a passageway in the end of one of the joined bodies. The rod is preferably slidably and rotatably received through the passageway, yet provides a selective fluid tight seal relative thereto. A recess is formed in the rod. When the recess and passageway are positioned to be coincident, fluid is permitted to flow through the passageway and around the rod. The pad is preferably laterally orientable relative to the rod and foldably retractable to within one of the bodies. A solvent is provided for wetting of the pad and solubilizing or suspending the material being sampled from a particular surface. 15 figs.

  10. Chain Sampling

    DTIC Science & Technology

    1972-08-01

    35609 Advanced Techniques Branch Plans and Programs Analysis Division Directorate for Product Assurance U. S. Army Missile Command Redstone Arsenal...Ray Heathcock Advanced Techniques Branch Plans and Programs Analysis Division Directorate for Product Assurance U. S. Army Missile Command...for Product Assurance has established a rather unique computer program for handling a variety of chain sampling schemes and is available for

  11. Granulocyte colony-stimulating factor improves host defense to resuscitated shock and polymicrobial sepsis without provoking generalized neutrophil-mediated damage.

    PubMed

    Patton, J H; Lyden, S P; Ragsdale, D N; Croce, M A; Fabian, T C; Proctor, K G

    1998-05-01

    Granulocyte colony-stimulating factor (G-CSF) increases production and release of neutrophil precursors and activates multiple functions of circulating polymorphonuclear neutrophils (PMNs). G-CSF has therapeutic effects in many experimental models of sepsis; its actions with superimposed reperfusion insults are unknown. In traumatic conditions, G-CSF could exacerbate unregulated, PMN-dependent injury to otherwise normal host tissue or, it could partially reverse trauma-induced immune suppression, which may improve long-term outcome. This study tested whether stimulating PMN proliferation and function with G-CSF during recovery from trauma+sepsis potentiated reperfusion injury or whether it improved host defense. Anesthetized swine were subjected to cecal ligation and incision, 35% hemorrhage, and 1 hr of hypotension. Resuscitation consisted of intravenous G-CSF (5 microg/kg) or placebo followed by shed blood and 40 mL/kg of lactated Ringer's solution. The control group received laparotomy only. G-CSF or placebo was given daily. Animals were killed at 4 days. Observers, blind to the protocol, graded autopsy samples for localization of infection and quality of abscess wall formation. Data included complete blood count, granulocyte oxidative burst after phorbol myristate acetate stimulation in vitro (GO2B), bronchoalveolar lavage (BAL) cell count, BAL noncellular protein, lipopolysaccharide-stimulated tumor necrosis factor production in whole blood in vitro (lipopolysaccharide-tumor necrosis factor), and lung tissue myeloperoxidase (MPO). Neutrophilia and localization of infection, were significantly improved by G-CSF. Variables altered by G-CSF, though not significantly, showed GO2B potential increased by 50%, lipopolysaccharide-tumor necrosis factor decreased by 50%, and improved survival versus placebo (100% vs. 70%). G-CSF did not increase lung MPO, BAL cell count, or BAL protein. Both arterial and venous O2 saturations were unaltered. Our data show that G

  12. Sampling Strategy

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Three locations to the right of the test dig area are identified for the first samples to be delivered to the Thermal and Evolved Gas Analyzer (TEGA), the Wet Chemistry Lab (WCL), and the Optical Microscope (OM) on NASA's Phoenix Mars Lander. These sampling areas are informally labeled 'Baby Bear', 'Mama Bear', and 'Papa Bear' respectively. This image was taken on the seventh day of the Mars mission, or Sol 7 (June 1, 2008) by the Surface Stereo Imager aboard NASA's Phoenix Mars Lander.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  13. Sampling Strategy

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Three locations to the right of the test dig area are identified for the first samples to be delivered to the Thermal and Evolved Gas Analyzer (TEGA), the Wet Chemistry Lab (WCL), and the Optical Microscope (OM) on NASA's Phoenix Mars Lander. These sampling areas are informally labeled 'Baby Bear', 'Mama Bear', and 'Papa Bear' respectively. This image was taken on the seventh day of the Mars mission, or Sol 7 (June 1, 2008) by the Surface Stereo Imager aboard NASA's Phoenix Mars Lander.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  14. Biorack - samples

    NASA Image and Video Library

    1997-01-13

    STS081-E-05145 (13 Jan. 1997) --- Astronaut John M. Grunsfeld, mission specialist, works with a Passive Thermal Conditioning Unit (PTCU), the cylindrical device suspended between the mission specialist and the nearby biorack glovebox onboard the Spacehab Double Module (DM). He holds a container of experiment samples in his left hand. This image was recorded with an Electronic Still Camera (ESC) and was later downlinked to flight controllers in Houston, Texas. Grunsfeld and five astronaut crew mates are preparing for a scheduled mid-week docking with Russia's Mir Space Station.

  15. Sample sequencing

    SciTech Connect

    Prange, C.

    1994-04-01

    The goal of the Human Genome Project is to sequence all 3 billion basepairs of human DNA. At Lawrence Livermore Lab, attention is focused on Chromosome 19, which has been estimated to contain approximately 2000 genes. So far, only 200 have been mapped to specific areas on the chromosome. For this reason, a simple method is needed to predict the most likely locations of the coding regions in the DNA. In addition, there is also a need for unique market sites (STS`s) along the chromosome. Sample sequencing uses standard cloning techniques to prepare DNA for sequencing. Once sequence is obtained, it is analyzed using databases to predict the regions most likely to contain genes. All sequences may also be used to generate STS`s. So far, 21 fragments from five different clones have been completely sequenced, with fragments from eight more clones in progress. Constant improvement of methods to increase efficiency and accuracy combined with utilization of the most current databases available make sample sequencing a useful tool for reaching the goals of the Human Genome Project.

  16. Automated Broad-Range Molecular Detection of Bacteria in Clinical Samples

    PubMed Central

    Hoogewerf, Martine; Vandenbroucke-Grauls, Christina M. J. E.; Savelkoul, Paul H. M.

    2016-01-01

    Molecular detection methods, such as quantitative PCR (qPCR), have found their way into clinical microbiology laboratories for the detection of an array of pathogens. Most routinely used methods, however, are directed at specific species. Thus, anything that is not explicitly searched for will be missed. This greatly limits the flexibility and universal application of these techniques. We investigated the application of a rapid universal bacterial molecular identification method, IS-pro, to routine patient samples received in a clinical microbiology laboratory. IS-pro is a eubacterial technique based on the detection and categorization of 16S-23S rRNA gene interspace regions with lengths that are specific for each microbial species. As this is an open technique, clinicians do not need to decide in advance what to look for. We compared routine culture to IS-pro using 66 samples sent in for routine bacterial diagnostic testing. The samples were obtained from patients with infections in normally sterile sites (without a resident microbiota). The results were identical in 20 (30%) samples, IS-pro detected more bacterial species than culture in 31 (47%) samples, and five of the 10 culture-negative samples were positive with IS-pro. The case histories of the five patients from whom these culture-negative/IS-pro-positive samples were obtained suggest that the IS-pro findings are highly clinically relevant. Our findings indicate that an open molecular approach, such as IS-pro, may have a high added value for clinical practice. PMID:26763956

  17. Utility of gram staining for evaluation of the quality of cystic fibrosis sputum samples.

    PubMed

    Nair, Bindu; Stapp, Jenny; Stapp, Lynn; Bugni, Linda; Van Dalfsen, Jill; Burns, Jane L

    2002-08-01

    The microscopic examination of Gram-stained sputum specimens is very helpful in the evaluation of patients with community-acquired pneumonia and has also been recommended for use in cystic fibrosis (CF) patients. This study was undertaken to evaluate that recommendation. One hundred one sputum samples from CF patients were cultured for gram-negative bacilli and examined by Gram staining for both sputum adequacy (using the quality [Q] score) and bacterial morphology. Subjective evaluation of adequacy was also performed and categorized. Based on Q score evaluation, 41% of the samples would have been rejected despite a subjective appearance of purulence. Only three of these rejected samples were culture negative for gram-negative CF pathogens. Correlation between culture results and quantitative Gram stain examination was also poor. These data suggest that subjective evaluation combined with comprehensive bacteriology is superior to Gram staining in identifying pathogens in CF sputum.

  18. Utility of Gram Staining for Evaluation of the Quality of Cystic Fibrosis Sputum Samples

    PubMed Central

    Nair, Bindu; Stapp, Jenny; Stapp, Lynn; Bugni, Linda; Van Dalfsen, Jill; Burns, Jane L.

    2002-01-01

    The microscopic examination of Gram-stained sputum specimens is very helpful in the evaluation of patients with community-acquired pneumonia and has also been recommended for use in cystic fibrosis (CF) patients. This study was undertaken to evaluate that recommendation. One hundred one sputum samples from CF patients were cultured for gram-negative bacilli and examined by Gram staining for both sputum adequacy (using the quality [Q] score) and bacterial morphology. Subjective evaluation of adequacy was also performed and categorized. Based on Q score evaluation, 41% of the samples would have been rejected despite a subjective appearance of purulence. Only three of these rejected samples were culture negative for gram-negative CF pathogens. Correlation between culture results and quantitative Gram stain examination was also poor. These data suggest that subjective evaluation combined with comprehensive bacteriology is superior to Gram staining in identifying pathogens in CF sputum. PMID:12149331

  19. Diagnosis of intramammary infection in samples yielding negative results or minor pathogens in conventional bacterial culturing.

    PubMed

    Bexiga, Ricardo; Koskinen, Mikko T; Holopainen, Jani; Carneiro, Carla; Pereira, Helena; Ellis, Kathryn A; Vilela, Cristina L

    2011-02-01

    Up to half of quarter milk samples submitted for mastitis diagnosis are culture-negative results or lead to identification of coagulase-negative staphylococci or Corynebacterium bovis in conventional culturing, the so-called minor pathogens. The interpretation and usefulness of these results in terms of udder and animal health management is limited, even though the amount of resources spent is relatively high. This work aimed to test two methods of analysis of milk samples with the goal of increasing detection of intramammary pathogens. In the first study, 783 milk samples were processed in duplicate: before and after freezing at -20°C for 24 h, using standard bacteriological techniques. There was a significant difference between the two methods with samples frozen for 24 h yielding significantly fewer Gram-positive catalase-positive cocci, Gram-negative bacilli, Gram-positive bacilli and significantly more samples leading to no growth, than samples before freezing. The number of samples yielding Gram-positive catalase-negative cocci was not significantly affected by freezing. In the second study, a real-time PCR-based test was performed on milk samples with an individual quarter somatic cell count above 500,000 cells/ml that were either negative (n=51 samples) or that led to the isolation of minor pathogens in culturing: Corynebacterium bovis (n=79 samples) or non-aureus staphylococci (NAS, n=32). A mastitis pathogen, beyond the result obtained with standard bacteriology, was detected on 47% of the no-growth samples, on 35% of the samples from which C. bovis had been isolated and on 25% of the samples from which NAS had been isolated. The most commonly detected major pathogen was Escherichia coli, followed by Streptococcus uberis, Arcanobacterium pyogenes/Peptoniphilus indolicus and Streptococcus dysgalactiae. These results suggest that simply freezing milk samples for 24 h does not increase the detection of intramammary bacteria in milk samples and therefore

  20. How Many Samples and How Many Culture Media To Diagnose a Prosthetic Joint Infection: a Clinical and Microbiological Prospective Multicenter Study

    PubMed Central

    Léger, Julie; Tandé, Didier; Plouzeau, Chloé; Valentin, Anne Sophie; Jolivet-Gougeon, Anne; Lemarié, Carole; Kempf, Marie; Héry-Arnaud, Geneviève; Bret, Laurent; Juvin, Marie Emmanuelle; Giraudeau, Bruno; Burucoa, Christophe

    2015-01-01

    Although numerous perioperative samples and culture media are required to diagnose prosthetic joint infection (PJI), their exact number and types have not yet been definitely determined with a high level of proof. We conducted a prospective multicenter study to determine the minimal number of samples and culture media required for accurate diagnosis of PJI. Over a 2-year period, consecutive patients with clinical signs suggesting PJI were included, with five perioperative samples per patient. The bacteriological and PJI diagnosis criteria were assessed using a random selection of two, three, or four samples and compared with those obtained using the recommended five samples (references guidelines). The results obtained with two or three culture media were then compared with those obtained with five culture media for both criteria. The times-to-positivity of the different culture media were calculated. PJI was confirmed in 215/264 suspected cases, with a bacteriological criterion in 192 (89%). The PJI was monomicrobial (85%) or polymicrobial (15%). Percentages of agreement of 98.1% and 99.7%, respectively, for the bacteriological criterion and confirmed PJI diagnosis were obtained when four perioperative samples were considered. The highest percentages of agreement were obtained with the association of three culture media, a blood culture bottle, a chocolate agar plate, and Schaedler broth, incubated for 5, 7, and 14 days, respectively. This new procedure leads to significant cost saving. Our prospective multicenter study showed that four samples seeded on three culture media are sufficient for diagnosing PJI. PMID:26637380

  1. How Many Samples and How Many Culture Media To Diagnose a Prosthetic Joint Infection: a Clinical and Microbiological Prospective Multicenter Study.

    PubMed

    Bémer, Pascale; Léger, Julie; Tandé, Didier; Plouzeau, Chloé; Valentin, Anne Sophie; Jolivet-Gougeon, Anne; Lemarié, Carole; Kempf, Marie; Héry-Arnaud, Geneviève; Bret, Laurent; Juvin, Marie Emmanuelle; Giraudeau, Bruno; Corvec, Stéphane; Burucoa, Christophe

    2016-02-01

    Although numerous perioperative samples and culture media are required to diagnose prosthetic joint infection (PJI), their exact number and types have not yet been definitely determined with a high level of proof. We conducted a prospective multicenter study to determine the minimal number of samples and culture media required for accurate diagnosis of PJI. Over a 2-year period, consecutive patients with clinical signs suggesting PJI were included, with five perioperative samples per patient. The bacteriological and PJI diagnosis criteria were assessed using a random selection of two, three, or four samples and compared with those obtained using the recommended five samples (references guidelines). The results obtained with two or three culture media were then compared with those obtained with five culture media for both criteria. The times-to-positivity of the different culture media were calculated. PJI was confirmed in 215/264 suspected cases, with a bacteriological criterion in 192 (89%). The PJI was monomicrobial (85%) or polymicrobial (15%). Percentages of agreement of 98.1% and 99.7%, respectively, for the bacteriological criterion and confirmed PJI diagnosis were obtained when four perioperative samples were considered. The highest percentages of agreement were obtained with the association of three culture media, a blood culture bottle, a chocolate agar plate, and Schaedler broth, incubated for 5, 7, and 14 days, respectively. This new procedure leads to significant cost saving. Our prospective multicenter study showed that four samples seeded on three culture media are sufficient for diagnosing PJI.

  2. Universal digital high-resolution melt: a novel approach to broad-based profiling of heterogeneous biological samples.

    PubMed

    Fraley, Stephanie I; Hardick, Justin; Masek, Billie J; Jo Masek, Billie; Athamanolap, Pornpat; Rothman, Richard E; Gaydos, Charlotte A; Carroll, Karen C; Wakefield, Teresa; Wang, Tza-Huei; Yang, Samuel

    2013-10-01

    Comprehensive profiling of nucleic acids in genetically heterogeneous samples is important for clinical and basic research applications. Universal digital high-resolution melt (U-dHRM) is a new approach to broad-based PCR diagnostics and profiling technologies that can overcome issues of poor sensitivity due to contaminating nucleic acids and poor specificity due to primer or probe hybridization inaccuracies for single nucleotide variations. The U-dHRM approach uses broad-based primers or ligated adapter sequences to universally amplify all nucleic acid molecules in a heterogeneous sample, which have been partitioned, as in digital PCR. Extensive assay optimization enables direct sequence identification by algorithm-based matching of melt curve shape and Tm to a database of known sequence-specific melt curves. We show that single-molecule detection and single nucleotide sensitivity is possible. The feasibility and utility of U-dHRM is demonstrated through detection of bacteria associated with polymicrobial blood infection and microRNAs (miRNAs) associated with host response to infection. U-dHRM using broad-based 16S rRNA gene primers demonstrates universal single cell detection of bacterial pathogens, even in the presence of larger amounts of contaminating bacteria; U-dHRM using universally adapted Lethal-7 miRNAs in a heterogeneous mixture showcases the single copy sensitivity and single nucleotide specificity of this approach.

  3. Coring Sample Acquisition Tool

    NASA Technical Reports Server (NTRS)

    Haddad, Nicolas E.; Murray, Saben D.; Walkemeyer, Phillip E.; Badescu, Mircea; Sherrit, Stewart; Bao, Xiaoqi; Kriechbaum, Kristopher L.; Richardson, Megan; Klein, Kerry J.

    2012-01-01

    A sample acquisition tool (SAT) has been developed that can be used autonomously to sample drill and capture rock cores. The tool is designed to accommodate core transfer using a sample tube to the IMSAH (integrated Mars sample acquisition and handling) SHEC (sample handling, encapsulation, and containerization) without ever touching the pristine core sample in the transfer process.

  4. Sampling by Length.

    ERIC Educational Resources Information Center

    Handley, John C.

    1991-01-01

    Discussion of sampling methods used in information science research focuses on Fussler's method for sampling catalog cards and on sampling by length. Highlights include simple random sampling, sampling with probability equal to size without replacement, sampling with replacement, and examples of estimating the number of books on shelves in certain…

  5. Acceptance sampling methods for sample results verification

    SciTech Connect

    Jesse, C.A.

    1993-06-01

    This report proposes a statistical sampling method for use during the sample results verification portion of the validation of data packages. In particular, this method was derived specifically for the validation of data packages for metals target analyte analysis performed under United States Environmental Protection Agency Contract Laboratory Program protocols, where sample results verification can be quite time consuming. The purpose of such a statistical method is to provide options in addition to the ``all or nothing`` options that currently exist for sample results verification. The proposed method allows the amount of data validated during the sample results verification process to be based on a balance between risks and the cost of inspection.

  6. Information sampling behavior with explicit sampling costs.

    PubMed

    Juni, Mordechai Z; Gureckis, Todd M; Maloney, Laurence T

    2016-07-01

    The decision to gather information should take into account both the value of information and its accrual costs in time, energy and money. Here we explore how people balance the monetary costs and benefits of gathering additional information in a perceptual-motor estimation task. Participants were rewarded for touching a hidden circular target on a touch-screen display. The target's center coincided with the mean of a circular Gaussian distribution from which participants could sample repeatedly. Each "cue" - sampled one at a time - was plotted as a dot on the display. Participants had to repeatedly decide, after sampling each cue, whether to stop sampling and attempt to touch the hidden target or continue sampling. Each additional cue increased the participants' probability of successfully touching the hidden target but reduced their potential reward. Two experimental conditions differed in the initial reward associated with touching the hidden target and the fixed cost per cue. For each condition we computed the optimal number of cues that participants should sample, before taking action, to maximize expected gain. Contrary to recent claims that people gather less information than they objectively should before taking action, we found that participants over-sampled in one experimental condition, and did not significantly under- or over-sample in the other. Additionally, while the ideal observer model ignores the current sample dispersion, we found that participants used it to decide whether to stop sampling and take action or continue sampling, a possible consequence of imperfect learning of the underlying population dispersion across trials.

  7. Utility of a Lateral Flow Immunoassay (LFI) to Detect Burkholderia pseudomallei in Soil Samples

    PubMed Central

    Rongkard, Patpong; Hantrakun, Viriya; Dittrich, Sabine; Srilohasin, Prapaporn; Amornchai, Premjit; Langla, Sayan; Lim, Cherry; Day, Nicholas P. J.; AuCoin, David; Wuthiekanun, Vanaporn

    2016-01-01

    Background Culture is the gold standard for the detection of environmental B. pseudomallei. In general, soil specimens are cultured in enrichment broth for 2 days, and then the culture broth is streaked on an agar plate and incubated further for 7 days. However, identifying B. pseudomallei on the agar plates among other soil microbes requires expertise and experience. Here, we evaluate a lateral flow immunoassay (LFI) developed to detect B. pseudomallei capsular polysaccharide (CPS) in clinical samples as a tool to detect B. pseudomallei in environmental samples. Methodology/Principal Findings First, we determined the limit of detection (LOD) of LFI for enrichment broth of the soil specimens. Soil specimens (10 grams/specimen) culture negative for B. pseudomallei were spiked with B. pseudomallei ranging from 10 to 105 CFU, and incubated in 10 ml of enrichment broth in air at 40°C. Then, on day 2, 4 and 7 of incubation, 50 μL of the upper layer of the broth were tested on the LFI, and colony counts to determine quantity of B. pseudomallei in the broth were performed. We found that all five soil specimens inoculated at 10 CFU were negative by LFI on day 2, but four of those five specimens were LFI positive on day 7. The LOD of the LFI was estimated to be roughly 3.8x106 CFU/ml, and culture broth on day 7 was selected as the optimal sample for LFI testing. Second, we evaluated the utility of the LFI by testing 105 soil samples from Northeast Thailand. All samples were also tested by standard culture and quantitative PCR (qPCR) targeting orf2. Of 105 soil samples, 35 (33%) were LFI positive, 25 (24%) were culture positive for B. pseudomallei, and 79 (75%) were qPCR positive. Of 11 LFI positive but standard culture negative specimens, six were confirmed by having the enrichment broth on day 7 culture positive for B. pseudomallei, and an additional three by qPCR. The LFI had 97% (30/31) sensitivity to detect soil specimens culture positive for B. pseudomallei

  8. Utility of a Lateral Flow Immunoassay (LFI) to Detect Burkholderia pseudomallei in Soil Samples.

    PubMed

    Rongkard, Patpong; Hantrakun, Viriya; Dittrich, Sabine; Srilohasin, Prapaporn; Amornchai, Premjit; Langla, Sayan; Lim, Cherry; Day, Nicholas P J; AuCoin, David; Wuthiekanun, Vanaporn; Limmathurotsakul, Direk

    2016-12-01

    Culture is the gold standard for the detection of environmental B. pseudomallei. In general, soil specimens are cultured in enrichment broth for 2 days, and then the culture broth is streaked on an agar plate and incubated further for 7 days. However, identifying B. pseudomallei on the agar plates among other soil microbes requires expertise and experience. Here, we evaluate a lateral flow immunoassay (LFI) developed to detect B. pseudomallei capsular polysaccharide (CPS) in clinical samples as a tool to detect B. pseudomallei in environmental samples. First, we determined the limit of detection (LOD) of LFI for enrichment broth of the soil specimens. Soil specimens (10 grams/specimen) culture negative for B. pseudomallei were spiked with B. pseudomallei ranging from 10 to 105 CFU, and incubated in 10 ml of enrichment broth in air at 40°C. Then, on day 2, 4 and 7 of incubation, 50 μL of the upper layer of the broth were tested on the LFI, and colony counts to determine quantity of B. pseudomallei in the broth were performed. We found that all five soil specimens inoculated at 10 CFU were negative by LFI on day 2, but four of those five specimens were LFI positive on day 7. The LOD of the LFI was estimated to be roughly 3.8x106 CFU/ml, and culture broth on day 7 was selected as the optimal sample for LFI testing. Second, we evaluated the utility of the LFI by testing 105 soil samples from Northeast Thailand. All samples were also tested by standard culture and quantitative PCR (qPCR) targeting orf2. Of 105 soil samples, 35 (33%) were LFI positive, 25 (24%) were culture positive for B. pseudomallei, and 79 (75%) were qPCR positive. Of 11 LFI positive but standard culture negative specimens, six were confirmed by having the enrichment broth on day 7 culture positive for B. pseudomallei, and an additional three by qPCR. The LFI had 97% (30/31) sensitivity to detect soil specimens culture positive for B. pseudomallei. The LFI can be used to detect B. pseudomallei in

  9. A Mars Sample Return Sample Handling System

    NASA Technical Reports Server (NTRS)

    Wilson, David; Stroker, Carol

    2013-01-01

    We present a sample handling system, a subsystem of the proposed Dragon landed Mars Sample Return (MSR) mission [1], that can return to Earth orbit a significant mass of frozen Mars samples potentially consisting of: rock cores, subsurface drilled rock and ice cuttings, pebble sized rocks, and soil scoops. The sample collection, storage, retrieval and packaging assumptions and concepts in this study are applicable for the NASA's MPPG MSR mission architecture options [2]. Our study assumes a predecessor rover mission collects samples for return to Earth to address questions on: past life, climate change, water history, age dating, understanding Mars interior evolution [3], and, human safety and in-situ resource utilization. Hence the rover will have "integrated priorities for rock sampling" [3] that cover collection of subaqueous or hydrothermal sediments, low-temperature fluidaltered rocks, unaltered igneous rocks, regolith and atmosphere samples. Samples could include: drilled rock cores, alluvial and fluvial deposits, subsurface ice and soils, clays, sulfates, salts including perchlorates, aeolian deposits, and concretions. Thus samples will have a broad range of bulk densities, and require for Earth based analysis where practical: in-situ characterization, management of degradation such as perchlorate deliquescence and volatile release, and contamination management. We propose to adopt a sample container with a set of cups each with a sample from a specific location. We considered two sample cups sizes: (1) a small cup sized for samples matching those submitted to in-situ characterization instruments, and, (2) a larger cup for 100 mm rock cores [4] and pebble sized rocks, thus providing diverse samples and optimizing the MSR sample mass payload fraction for a given payload volume. We minimize sample degradation by keeping them frozen in the MSR payload sample canister using Peltier chip cooling. The cups are sealed by interference fitted heat activated memory

  10. Ranked set sampling with unequal samples.

    PubMed

    Bhoj, D S

    2001-09-01

    A ranked set sampling procedure with unequal samples (RSSU) is proposed and used to estimate the population mean. This estimator is then compared with the estimators based on the ranked set sampling (RSS) and median ranked set sampling (MRSS) procedures. It is shown that the relative precisions of the estimator based on RSSU are higher than those of the estimators based on RSS and MRSS. An example of estimating the mean diameter at breast height of longleaf-pine trees on the Wade Tract in Thomas County, Georgia, is presented.

  11. Information sampling behavior with explicit sampling costs

    PubMed Central

    Juni, Mordechai Z.; Gureckis, Todd M.; Maloney, Laurence T.

    2015-01-01

    The decision to gather information should take into account both the value of information and its accrual costs in time, energy and money. Here we explore how people balance the monetary costs and benefits of gathering additional information in a perceptual-motor estimation task. Participants were rewarded for touching a hidden circular target on a touch-screen display. The target’s center coincided with the mean of a circular Gaussian distribution from which participants could sample repeatedly. Each “cue” — sampled one at a time — was plotted as a dot on the display. Participants had to repeatedly decide, after sampling each cue, whether to stop sampling and attempt to touch the hidden target or continue sampling. Each additional cue increased the participants’ probability of successfully touching the hidden target but reduced their potential reward. Two experimental conditions differed in the initial reward associated with touching the hidden target and the fixed cost per cue. For each condition we computed the optimal number of cues that participants should sample, before taking action, to maximize expected gain. Contrary to recent claims that people gather less information than they objectively should before taking action, we found that participants over-sampled in one experimental condition, and did not significantly under- or over-sample in the other. Additionally, while the ideal observer model ignores the current sample dispersion, we found that participants used it to decide whether to stop sampling and take action or continue sampling, a possible consequence of imperfect learning of the underlying population dispersion across trials. PMID:27429991

  12. How Sample Size Affects a Sampling Distribution

    ERIC Educational Resources Information Center

    Mulekar, Madhuri S.; Siegel, Murray H.

    2009-01-01

    If students are to understand inferential statistics successfully, they must have a profound understanding of the nature of the sampling distribution. Specifically, they must comprehend the determination of the expected value and standard error of a sampling distribution as well as the meaning of the central limit theorem. Many students in a high…

  13. How Sample Size Affects a Sampling Distribution

    ERIC Educational Resources Information Center

    Mulekar, Madhuri S.; Siegel, Murray H.

    2009-01-01

    If students are to understand inferential statistics successfully, they must have a profound understanding of the nature of the sampling distribution. Specifically, they must comprehend the determination of the expected value and standard error of a sampling distribution as well as the meaning of the central limit theorem. Many students in a high…

  14. Comet Surface Sampling Technologies

    NASA Astrophysics Data System (ADS)

    Zacny, K.; Chu, P.; Paulsen, G.; Indyk, S.

    2014-06-01

    The goal of the Comet Surface Sample Return (CSSR) is to acquire and return to Earth a ≥500 cc) sample. Honeybee developed several sampling technologies including a standalone CSSR Probe (CSSRP) and Pyramid Comet Sampler (PyCoS).

  15. Chorionic Villus Sampling (CVS)

    MedlinePlus

    ... Pregnancy > Prenatal care > Chorionic villus sampling Chorionic villus sampling E-mail to a friend Please fill in ... It's been added to your dashboard . Chorionic villus sampling (CVS) is a prenatal test . It’s used to ...

  16. From Sample to Multi-Omics Conclusions in under 48 Hours.

    PubMed

    Quinn, Robert A; Navas-Molina, Jose A; Hyde, Embriette R; Song, Se Jin; Vázquez-Baeza, Yoshiki; Humphrey, Greg; Gaffney, James; Minich, Jeremiah J; Melnik, Alexey V; Herschend, Jakob; DeReus, Jeff; Durant, Austin; Dutton, Rachel J; Khosroheidari, Mahdieh; Green, Clifford; da Silva, Ricardo; Dorrestein, Pieter C; Knight, Rob

    2016-01-01

    Multi-omics methods have greatly advanced our understanding of the biological organism and its microbial associates. However, they are not routinely used in clinical or industrial applications, due to the length of time required to generate and analyze omics data. Here, we applied a novel integrated omics pipeline for the analysis of human and environmental samples in under 48 h. Human subjects that ferment their own foods provided swab samples from skin, feces, oral cavity, fermented foods, and household surfaces to assess the impact of home food fermentation on their microbial and chemical ecology. These samples were analyzed with 16S rRNA gene sequencing, inferred gene function profiles, and liquid chromatography-tandem mass spectrometry (LC-MS/MS) metabolomics through the Qiita, PICRUSt, and GNPS pipelines, respectively. The human sample microbiomes clustered with the corresponding sample types in the American Gut Project (http://www.americangut.org), and the fermented food samples produced a separate cluster. The microbial communities of the household surfaces were primarily sourced from the fermented foods, and their consumption was associated with increased gut microbial diversity. Untargeted metabolomics revealed that human skin and fermented food samples had separate chemical ecologies and that stool was more similar to fermented foods than to other sample types. Metabolites from the fermented foods, including plant products such as procyanidin and pheophytin, were present in the skin and stool samples of the individuals consuming the foods. Some food metabolites were modified during digestion, and others were detected in stool intact. This study represents a first-of-its-kind analysis of multi-omics data that achieved time intervals matching those of classic microbiological culturing. IMPORTANCE Polymicrobial infections are difficult to diagnose due to the challenge in comprehensively cultivating the microbes present. Omics methods, such as 16S r

  17. From Sample to Multi-Omics Conclusions in under 48 Hours

    PubMed Central

    Navas-Molina, Jose A.; Hyde, Embriette R.; Vázquez-Baeza, Yoshiki; Humphrey, Greg; Gaffney, James; Minich, Jeremiah J.; Melnik, Alexey V.; Herschend, Jakob; DeReus, Jeff; Durant, Austin; Dutton, Rachel J.; Khosroheidari, Mahdieh; Green, Clifford; da Silva, Ricardo; Dorrestein, Pieter C.; Knight, Rob

    2016-01-01

    ABSTRACT Multi-omics methods have greatly advanced our understanding of the biological organism and its microbial associates. However, they are not routinely used in clinical or industrial applications, due to the length of time required to generate and analyze omics data. Here, we applied a novel integrated omics pipeline for the analysis of human and environmental samples in under 48 h. Human subjects that ferment their own foods provided swab samples from skin, feces, oral cavity, fermented foods, and household surfaces to assess the impact of home food fermentation on their microbial and chemical ecology. These samples were analyzed with 16S rRNA gene sequencing, inferred gene function profiles, and liquid chromatography-tandem mass spectrometry (LC-MS/MS) metabolomics through the Qiita, PICRUSt, and GNPS pipelines, respectively. The human sample microbiomes clustered with the corresponding sample types in the American Gut Project (http://www.americangut.org), and the fermented food samples produced a separate cluster. The microbial communities of the household surfaces were primarily sourced from the fermented foods, and their consumption was associated with increased gut microbial diversity. Untargeted metabolomics revealed that human skin and fermented food samples had separate chemical ecologies and that stool was more similar to fermented foods than to other sample types. Metabolites from the fermented foods, including plant products such as procyanidin and pheophytin, were present in the skin and stool samples of the individuals consuming the foods. Some food metabolites were modified during digestion, and others were detected in stool intact. This study represents a first-of-its-kind analysis of multi-omics data that achieved time intervals matching those of classic microbiological culturing. IMPORTANCE Polymicrobial infections are difficult to diagnose due to the challenge in comprehensively cultivating the microbes present. Omics methods, such as 16S

  18. Five Years' Evaluation of the BD ProbeTec System for the Direct Molecular Detection of Mycobacterium tuberculosis Complex in Respiratory and Nonrespiratory Clinical Samples.

    PubMed

    Bicmen, Can; Karaman, Onur; Gunduz, Ayriz T; Erer, Onur F; Coskun, Meral; Kaftan, Osman; Demirel, Mahmut M; Senol, Gunes; Akarca, Tulay; Dereli, Sevket; Ozsoz, Ayse

    2015-01-01

    In this study, Mycobacterium tuberculosis complex was detected by BD ProbeTec ET system in 4716 respiratory and 167 nonrespiratory samples [mostly (98%) smear negative). Sensitivity, specificity, positive and negative predictive values were 81.8%, 98.3, 85.1 and 97.9 for respiratory and 100%, 96.2, 64.7 and 100, for nonrespiratory samples, respectively. Among 149 (3.1%) ProbeTec DTB positive and culture negative samples, 72 (65 respiratory and seven nonrespiratory) (48.3%) were recovered from the patients who were evaluated as having TB infection. The system has been found as useful in early diagnosis of tuberculosis infection in association with the clinical, radiological and histopathological findings.

  19. Selecting a Sample

    ERIC Educational Resources Information Center

    Ritter, Lois A., Ed.; Sue, Valerie M., Ed.

    2007-01-01

    This chapter provides an overview of sampling methods that are appropriate for conducting online surveys. The authors review some of the basic concepts relevant to online survey sampling, present some probability and nonprobability techniques for selecting a sample, and briefly discuss sample size determination and nonresponse bias. Although some…

  20. Fluid sampling tool

    DOEpatents

    Garcia, Anthony R.; Johnston, Roger G.; Martinez, Ronald K.

    2000-01-01

    A fluid-sampling tool for obtaining a fluid sample from a container. When used in combination with a rotatable drill, the tool bores a hole into a container wall, withdraws a fluid sample from the container, and seals the borehole. The tool collects fluid sample without exposing the operator or the environment to the fluid or to wall shavings from the container.

  1. Identification of bacteria directly from positive blood culture samples by DNA pyrosequencing of the 16S rRNA gene.

    PubMed

    Motoshima, Maiko; Yanagihara, Katsunori; Morinaga, Yoshitomo; Matsuda, Junichi; Hasegawa, Hiroo; Kohno, Shigeru; Kamihira, Shimeru

    2012-11-01

    Rapid identification of the causative bacteria of sepsis in patients can contribute to the selection of appropriate antibiotics and improvement of patients' prognosis. Genotypic identification is an emerging technology that may provide an alternative method to, or complement, established phenotypic identification procedures. We evaluated a rapid protocol for bacterial identification based on PCR and pyrosequencing of the V1 and V3 regions of the 16S rRNA gene using DNA extracted directly from positive blood culture samples. One hundred and two positive blood culture bottles from 68 patients were randomly selected and the bacteria were identified by phenotyping and pyrosequencing. The results of pyrosequencing identification displayed 84.3 and 64.7 % concordance with the results of phenotypic identification at the genus and species levels, respectively. In the monomicrobial samples, the concordance between the results of pyrosequencing and phenotypic identification at the genus level was 87.0 %. Pyrosequencing identified one isolate in 60 % of polymicrobial samples, which were confirmed by culture analysis. Of the samples identified by pyrosequencing, 55.7 % showed consistent results in V1 and V3 targeted sequencing; other samples were identified based on the results of V1 (12.5 %) or V3 (31.8 %) sequencing alone. One isolate was erroneously identified by pyrosequencing due to high sequence similarity with another isolate. Pyrosequencing identified one isolate that was not detected by phenotypic identification. The process of pyrosequencing identification can be completed within ~4 h. The information provided by DNA-pyrosequencing for the identification of micro-organisms in positive blood culture bottles is accurate and could prove to be a rapid and useful tool in standard laboratory practice.

  2. Detection of Aspergillus fumigatus by quantitative polymerase chain reaction in air samples impacted on low-melt agar.

    PubMed

    Bellanger, Anne-Pauline; Reboux, Gabriel; Murat, Jean-Benjamin; Bex, Valerie; Millon, Laurence

    2010-04-01

    The standard procedure for routine environmental sampling for the prevention of invasive aspergillosis outbreaks is culturing of Aspergillus fumigatus after impaction of air. Time to results is usually 7 days. A preliminary study was carried out to compare the time to results and sensitivity of culturing and quantitative polymerase chain reaction (QPCR) in the detection of airborne A fumigatus. Fungal DNA was extracted from 43 samples of impacted low-melt agar by a 3-step extraction method and amplified by QPCR. Identification was made using a specific A fumigatus probe. With QPCR, 19 of the 43 samples were positive for A fumigatus; with culturing, 7 of these 19 samples were positive, and 12 were negative. The cycle threshold (Ct) values for the 12 culture-negative samples were between 39 and 43 cycles, and the Ct values for 6 of the 7 culture-positive samples were <38 cycles, suggesting that the amount of DNA detected by QPCR was higher in the presence of viable conidia. QPCR detection of airborne A fumigatus in impacted low-melt agar significantly reduces the period of time between sample collection and results (48 hours), suggesting that this new approach can be beneficial for routine environmental sampling. 2010 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

  3. Enhanced conformational sampling using enveloping distribution sampling.

    PubMed

    Lin, Zhixiong; van Gunsteren, Wilfred F

    2013-10-14

    To lessen the problem of insufficient conformational sampling in biomolecular simulations is still a major challenge in computational biochemistry. In this article, an application of the method of enveloping distribution sampling (EDS) is proposed that addresses this challenge and its sampling efficiency is demonstrated in simulations of a hexa-β-peptide whose conformational equilibrium encompasses two different helical folds, i.e., a right-handed 2.7(10∕12)-helix and a left-handed 3(14)-helix, separated by a high energy barrier. Standard MD simulations of this peptide using the GROMOS 53A6 force field did not reach convergence of the free enthalpy difference between the two helices even after 500 ns of simulation time. The use of soft-core non-bonded interactions in the centre of the peptide did enhance the number of transitions between the helices, but at the same time led to neglect of relevant helical configurations. In the simulations of a two-state EDS reference Hamiltonian that envelops both the physical peptide and the soft-core peptide, sampling of the conformational space of the physical peptide ensures that physically relevant conformations can be visited, and sampling of the conformational space of the soft-core peptide helps to enhance the transitions between the two helices. The EDS simulations sampled many more transitions between the two helices and showed much faster convergence of the relative free enthalpy of the two helices compared with the standard MD simulations with only a slightly larger computational effort to determine optimized EDS parameters. Combined with various methods to smoothen the potential energy surface, the proposed EDS application will be a powerful technique to enhance the sampling efficiency in biomolecular simulations.

  4. Sample Vial Secure Container

    SciTech Connect

    Baumann, M.J.

    1993-07-01

    International Atomic Energy Agency (IAEA) inspectors must maintain continuity of knowledge on all safeguard samples and, in particular, on those samples drawn from plutonium product and spent fuel input tanks at a nuclear reprocessing plant`s blister sampling station. Integrity of safeguard samples must be guaranteed from the sampling point to the moment of sample analysis at an accepted local laboratory or at the IAEA`s Safeguards Analytical Laboratory (SAL) in Seibersdorf, Austria. The safeguard samples are drawn at a blister sampling station with inspector participation and then transferred via a pneumatic post system to the facility`s analytical laboratory. Transfer of the sample by the pneumatic post system, arrival of the sample in the operator`s analytical laboratory, and storage of the sample awaiting analysis are very time consuming activities for an inspector, particularly if continuous human surveillance is required for all these activities. These activities could be observed by ordinary surveillance methods, such as a video monitoring system, but this would be cumbersome and time consuming for both the inspector and the operator. This paper describes a secure container designed to assure sample vial integrity from the point the sample is drawn to treatment of the sample at a facility`s analytical laboratory.

  5. Apollo 14 rock samples

    NASA Technical Reports Server (NTRS)

    Carlson, I. C.

    1978-01-01

    Petrographic descriptions of all Apollo 14 samples larger than 1 cm in any dimension are presented. The sample description format consists of: (1) an introductory section which includes information on lunar sample location, orientation, and return containers, (2) a section on physical characteristics, which contains the sample mass, dimensions, and a brief description; (3) surface features, including zap pits, cavities, and fractures as seen in binocular view; (4) petrographic description, consisting of a binocular description and, if possible, a thin section description; and (5) a discussion of literature relevant to sample petrology is included for samples which have previously been examined by the scientific community.

  6. Rain sampling device

    DOEpatents

    Nelson, Danny A.; Tomich, Stanley D.; Glover, Donald W.; Allen, Errol V.; Hales, Jeremy M.; Dana, Marshall T.

    1991-01-01

    The present invention constitutes a rain sampling device adapted for independent operation at locations remote from the user which allows rainfall to be sampled in accordance with any schedule desired by the user. The rain sampling device includes a mechanism for directing wet precipitation into a chamber, a chamber for temporarily holding the precipitation during the process of collection, a valve mechanism for controllably releasing samples of said precipitation from said chamber, a means for distributing the samples released from the holding chamber into vessels adapted for permanently retaining these samples, and an electrical mechanism for regulating the operation of the device.

  7. Stardust Sample: Investigator's Guidebook

    NASA Technical Reports Server (NTRS)

    Allen, Carl

    2006-01-01

    In January 2006, the Stardust spacecraft returned the first in situ collection of samples from a comet, and the first samples of contemporary interstellar dust. Stardust is the first US sample return mission from a planetary body since Apollo, and the first ever from beyond the moon. This handbook is a basic reference source for allocation procedures and policies for Stardust samples. These samples consist of particles and particle residues in aerogel collectors, in aluminum foil, and in spacecraft components. Contamination control samples and unflown collection media are also available for allocation.

  8. Rain sampling device

    DOEpatents

    Nelson, D.A.; Tomich, S.D.; Glover, D.W.; Allen, E.V.; Hales, J.M.; Dana, M.T.

    1991-05-14

    The present invention constitutes a rain sampling device adapted for independent operation at locations remote from the user which allows rainfall to be sampled in accordance with any schedule desired by the user. The rain sampling device includes a mechanism for directing wet precipitation into a chamber, a chamber for temporarily holding the precipitation during the process of collection, a valve mechanism for controllably releasing samples of the precipitation from the chamber, a means for distributing the samples released from the holding chamber into vessels adapted for permanently retaining these samples, and an electrical mechanism for regulating the operation of the device. 11 figures.

  9. Potential bacterial core species associated with digital dermatitis in cattle herds identified by molecular profiling of interdigital skin samples.

    PubMed

    Nielsen, Martin W; Strube, Mikael L; Isbrand, Anastasia; Al-Medrasi, Worood D H M; Boye, Mette; Jensen, Tim K; Klitgaard, Kirstine

    2016-04-15

    Although treponemes are consistently identified in tissue from bovine digital dermatitis (DD) lesions, the definitive etiology of this debilitating polymicrobial disease is still unresolved. To study the microbiomes of 27 DD-infected and 10 healthy interdigital skin samples, we used a combination of different molecular methods. Deep sequencing of the 16S rRNA gene variable regions V1-V2 showed that Treponema, Mycoplasma, Fusobacterium and Porphyromonas were the genera best differentiating the DD samples from the controls. Additional deep sequencing analysis of the most abundant genus, Treponema, targeting another variable region of the 16S rRNA gene, V3-V4, identified 15 different phylotypes, among which Treponema phagedenis-like and Treponema refringens-like species were the most abundant. Although the presence of Treponema spp., Fusobacterium necrophorum and Porphyromonas levii was confirmed by fluorescence in situ hybridization (FISH), the results for Mycoplasma spp. were inconclusive. Extensive treponemal epidermal infiltration, constituting more than 90% of the total bacterial population, was observed in 24 of the 27 DD samples. F. necrophorum and P. levii were superficially located in the epidermal lesions and were present in only a subset of samples. RT-qPCR analysis showed that treponemes were also actively expressing a panel of virulence factors at the site of infection. Our results further support the hypothesis that species belonging to the genus Treponema are major pathogens of DD and also provide sufficient clues to motivate additional research into the role of M. fermentans, F. necrophorum and P. levii in the etiology of DD. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  10. Improved Sampling Method Reduces Isokinetic Sampling Errors.

    ERIC Educational Resources Information Center

    Karels, Gale G.

    The particulate sampling system currently in use by the Bay Area Air Pollution Control District, San Francisco, California is described in this presentation for the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971. The method represents a practical, inexpensive tool that can…

  11. Improved Sampling Method Reduces Isokinetic Sampling Errors.

    ERIC Educational Resources Information Center

    Karels, Gale G.

    The particulate sampling system currently in use by the Bay Area Air Pollution Control District, San Francisco, California is described in this presentation for the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971. The method represents a practical, inexpensive tool that can…

  12. GROUND WATER SAMPLING ISSUES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and
    remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  13. GROUND WATER SAMPLING ISSUES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and
    remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  14. Mold Testing or Sampling

    EPA Pesticide Factsheets

    In most cases, if visible mold growth is present, sampling is unnecessary. Since no EPA or other federal limits have been set for mold or mold spores, sampling cannot be used to check a building's compliance with federal mold standards.

  15. Developing Water Sampling Standards

    ERIC Educational Resources Information Center

    Environmental Science and Technology, 1974

    1974-01-01

    Participants in the D-19 symposium on aquatic sampling and measurement for water pollution assessment were informed that determining the extent of waste water stream pollution is not a cut and dry procedure. Topics discussed include field sampling, representative sampling from storm sewers, suggested sampler features and application of improved…

  16. Decision by Sampling

    ERIC Educational Resources Information Center

    Stewart, Neil; Chater, Nick; Brown, Gordon D. A.

    2006-01-01

    We present a theory of decision by sampling (DbS) in which, in contrast with traditional models, there are no underlying psychoeconomic scales. Instead, we assume that an attribute's subjective value is constructed from a series of binary, ordinal comparisons to a sample of attribute values drawn from memory and is its rank within the sample. We…

  17. Randomized branch sampling

    Treesearch

    Harry T. Valentine

    2002-01-01

    Randomized branch sampling (RBS) is a special application of multistage probability sampling (see Sampling, environmental), which was developed originally by Jessen [3] to estimate fruit counts on individual orchard trees. In general, the method can be used to obtain estimates of many different attributes of trees or other branched plants. The usual objective of RBS is...

  18. SAMPLING OF CONTAMINATED SITES

    EPA Science Inventory

    A critical aspect of characterization of the amount and species of contamination of a hazardous waste site is the sampling plan developed for that site. f the sampling plan is not thoroughly conceptualized before sampling takes place, then certain critical aspects of the limits o...

  19. SAMPLING OF CONTAMINATED SITES

    EPA Science Inventory

    A critical aspect of characterization of the amount and species of contamination of a hazardous waste site is the sampling plan developed for that site. f the sampling plan is not thoroughly conceptualized before sampling takes place, then certain critical aspects of the limits o...

  20. Fluid sampling pump

    SciTech Connect

    Allen, P.V.; Nimberger, M.; Ward, R.L.

    1991-12-24

    This patent describes a fluid sampling pump for withdrawing pressurized sample fluid from a flow line and for pumping a preselected quantity of sample fluid with each pump driving stroke from the pump to a sample vessel, the sampling pump including a pump body defining a pump bore therein having a central axis, a piston slideably moveable within the pump bore and having a fluid inlet end and an opposing operator end, a fluid sample inlet port open to sample fluid in the flow line, a fluid sample outlet port for transmitting fluid from the pump bore to the sample vessel, and a line pressure port in fluid pressure sample fluid in the flow line, an inlet valve for selectively controlling sample fluid flow from the flow line through the fluid sample inlet port, an operator unit for periodically reciprocating the piston within the pump bore, and a controller for regulating the stroke of the piston within the pump bore, and thereby the quantity of fluid pumped with each pump driving stroke. It comprises a balanced check valve seat; a balanced check valve seal; a compression member; and a central plunger.

  1. Developing Water Sampling Standards

    ERIC Educational Resources Information Center

    Environmental Science and Technology, 1974

    1974-01-01

    Participants in the D-19 symposium on aquatic sampling and measurement for water pollution assessment were informed that determining the extent of waste water stream pollution is not a cut and dry procedure. Topics discussed include field sampling, representative sampling from storm sewers, suggested sampler features and application of improved…

  2. Instructions for Sampling Particulates.

    ERIC Educational Resources Information Center

    Ekman, Frank

    This technical report presents detailed instructions for sampling particulates. The table of contents includes sections on Introduction, Volume Determinations, Apparatus - Assembly and Operation, Sampling Techniques, and Acknowledgment. Six charts, 24 graphs, and one diagram are appended to facilitate sampling, as well as sections on Isokinetic…

  3. Aerosol sampling system

    DOEpatents

    Masquelier, Donald A.

    2004-02-10

    A system for sampling air and collecting particulate of a predetermined particle size range. A low pass section has an opening of a preselected size for gathering the air but excluding particles larger than the sample particles. An impactor section is connected to the low pass section and separates the air flow into a bypass air flow that does not contain the sample particles and a product air flow that does contain the sample particles. A wetted-wall cyclone collector, connected to the impactor section, receives the product air flow and traps the sample particles in a liquid.

  4. Rockballer Sample Acquisition Tool

    NASA Technical Reports Server (NTRS)

    Giersch, Louis R.; Cook, Brant T.

    2013-01-01

    It would be desirable to acquire rock and/or ice samples that extend below the surface of the parent rock or ice in extraterrestrial environments such as the Moon, Mars, comets, and asteroids. Such samples would allow measurements to be made further back into the geologic history of the rock, providing critical insight into the history of the local environment and the solar system. Such samples could also be necessary for sample return mission architectures that would acquire samples from extraterrestrial environments for return to Earth for more detailed scientific investigation.

  5. DIY Tomography sample holder

    NASA Astrophysics Data System (ADS)

    Lari, L.; Wright, I.; Boyes, E. D.

    2015-10-01

    A very simple tomography sample holder at minimal cost was developed in-house. The holder is based on a JEOL single tilt fast exchange sample holder where its exchangeable tip was modified to allow high angle degree tilt. The shape of the tip was designed to retain mechanical stability while minimising the lateral size of the tip. The sample can be mounted on as for a standard 3mm Cu grids as well as semi-circular grids from FIB sample preparation. Applications of the holder on different sample systems are shown.

  6. Venus Sample Return Mission

    NASA Astrophysics Data System (ADS)

    Whitcomb, G.; Lebreton, J.; Scoon, G.

    The Venus Sample Return (VSR) mission was performed as an in-house activity within the European Space Agency's Science Directorate during a 4-month period. The selected baseline mission scenario involves two launches of the presently available Ariane 5 configuration. The first launch would inject a composite spacecraft consisting of an orbiter and a return capsule into a parking orbit around Venus. The second launch would deliver at Venus a lander composite, consisting of the entry, descent, sampling and ascent modules. The sampling strategy includes returning a surface (with possibly a core) sample and three atmospheric samples at high altitudes. This paper presents the design concept for the mission.

  7. Sample Caching Subsystem

    NASA Technical Reports Server (NTRS)

    Backes, Paul G.; Collins, Curtis L.

    2007-01-01

    A paper describes the Sample Caching Subsystem (SCS), a method for storing planetary core and soil samples in a container that seals the samples away from the environment to protect the integrity of the samples and any organics they might contain. This process places samples in individual sleeves that are sealed within a container for use by either the current mission or by following missions. A sample container is stored with its sleeves partially inserted. When a sample is ready to be contained, a transfer arm rotates over and grasps a sleeve, pulls it out of the container from below, rotates over and inserts the sleeve into a funnel where it is passively locked into place and then released from the arm. An external sampling tool deposits the sample into the sleeve, which is aligned with the tool via passive compliance of the funnel. After the sampling tool leaves the funnel, the arm retrieves the sleeve and inserts it all the way into the sample container. This action engages the seal. Full containers can be left behind for pick-up by subsequent science missions, and container dimensions are compatible for placement in a Mars Ascent Vehicle for later return to Earth.

  8. Curation of Frozen Samples

    NASA Technical Reports Server (NTRS)

    Fletcher, L. A.; Allen, C. C.; Bastien, R.

    2008-01-01

    NASA's Johnson Space Center (JSC) and the Astromaterials Curator are charged by NPD 7100.10D with the curation of all of NASA s extraterrestrial samples, including those from future missions. This responsibility includes the development of new sample handling and preparation techniques; therefore, the Astromaterials Curator must begin developing procedures to preserve, prepare and ship samples at sub-freezing temperatures in order to enable future sample return missions. Such missions might include the return of future frozen samples from permanently-shadowed lunar craters, the nuclei of comets, the surface of Mars, etc. We are demonstrating the ability to curate samples under cold conditions by designing, installing and testing a cold curation glovebox. This glovebox will allow us to store, document, manipulate and subdivide frozen samples while quantifying and minimizing contamination throughout the curation process.

  9. Sample Proficiency Test exercise

    SciTech Connect

    Alcaraz, A; Gregg, H; Koester, C

    2006-02-05

    The current format of the OPCW proficiency tests has multiple sets of 2 samples sent to an analysis laboratory. In each sample set, one is identified as a sample, the other as a blank. This method of conducting proficiency tests differs from how an OPCW designated laboratory would receive authentic samples (a set of three containers, each not identified, consisting of the authentic sample, a control sample, and a blank sample). This exercise was designed to test the reporting if the proficiency tests were to be conducted. As such, this is not an official OPCW proficiency test, and the attached report is one method by which LLNL might report their analyses under a more realistic testing scheme. Therefore, the title on the report ''Report of the Umpteenth Official OPCW Proficiency Test'' is meaningless, and provides a bit of whimsy for the analyses and readers of the report.

  10. Sample size calculations.

    PubMed

    Noordzij, Marlies; Dekker, Friedo W; Zoccali, Carmine; Jager, Kitty J

    2011-01-01

    The sample size is the number of patients or other experimental units that need to be included in a study to answer the research question. Pre-study calculation of the sample size is important; if a sample size is too small, one will not be able to detect an effect, while a sample that is too large may be a waste of time and money. Methods to calculate the sample size are explained in statistical textbooks, but because there are many different formulas available, it can be difficult for investigators to decide which method to use. Moreover, these calculations are prone to errors, because small changes in the selected parameters can lead to large differences in the sample size. This paper explains the basic principles of sample size calculations and demonstrates how to perform such a calculation for a simple study design.

  11. The Lunar Sample Compendium

    NASA Technical Reports Server (NTRS)

    Meyer, Charles

    2009-01-01

    The Lunar Sample Compendium is a succinct summary of the data obtained from 40 years of study of Apollo and Luna samples of the Moon. Basic petrographic, chemical and age information is compiled, sample-by-sample, in the form of an advanced catalog in order to provide a basic description of each sample. The LSC can be found online using Google. The initial allocation of lunar samples was done sparingly, because it was realized that scientific techniques would improve over the years and new questions would be formulated. The LSC is important because it enables scientists to select samples within the context of the work that has already been done and facilitates better review of proposed allocations. It also provides back up material for public displays, captures information found only in abstracts, grey literature and curatorial databases and serves as a ready access to the now-vast scientific literature.

  12. The Lunar Sample Compendium

    NASA Technical Reports Server (NTRS)

    Meyer, Charles

    2009-01-01

    The Lunar Sample Compendium is a succinct summary of the data obtained from 40 years of study of Apollo and Luna samples of the Moon. Basic petrographic, chemical and age information is compiled, sample-by-sample, in the form of an advanced catalog in order to provide a basic description of each sample. The LSC can be found online using Google. The initial allocation of lunar samples was done sparingly, because it was realized that scientific techniques would improve over the years and new questions would be formulated. The LSC is important because it enables scientists to select samples within the context of the work that has already been done and facilitates better review of proposed allocations. It also provides back up material for public displays, captures information found only in abstracts, grey literature and curatorial databases and serves as a ready access to the now-vast scientific literature.

  13. Lunar Sample Compendium

    NASA Technical Reports Server (NTRS)

    Meyer, C.

    2009-01-01

    The Lunar Sample Compendium is a succinct summary of what has been learned from the study of Apollo and Luna samples of the Moon. Basic information is compiled, sample-by-sample, in the form of an advanced catalog in order to provide a basic description of each sample. Information presented is carefully attributed to the original source publication, thus the Compendium also serves as a ready access to the now vast scientific literature pertaining to lunar smples. The Lunar Sample Compendium is a work in progress (and may always be). Future plans include: adding sections on additional samples, adding new thin section photomicrographs, replacing the faded photographs with newly digitized photos from the original negatives, attempting to correct the age data using modern decay constants, adding references to each section, and adding an internal search engine.

  14. Urine sample collection protocols for bioassay samples

    SciTech Connect

    MacLellan, J.A.; McFadden, K.M.

    1992-11-01

    In vitro radiobioassay analyses are used to measure the amount of radioactive material excreted by personnel exposed to the potential intake of radioactive material. The analytical results are then used with various metabolic models to estimate the amount of radioactive material in the subject`s body and the original intake of radioactive material. Proper application of these metabolic models requires knowledge of the excretion period. It is normal practice to design the bioassay program based on a 24-hour excretion sample. The Hanford bioassay program simulates a total 24-hour urine excretion sample with urine collection periods lasting from one-half hour before retiring to one-half hour after rising on two consecutive days. Urine passed during the specified periods is collected in three 1-L bottles. Because the daily excretion volume given in Publication 23 of the International Commission on Radiological Protection (ICRP 1975, p. 354) for Reference Man is 1.4 L, it was proposed to use only two 1-L bottles as a cost-saving measure. This raised the broader question of what should be the design capacity of a 24-hour urine sample kit.

  15. Urine sample collection protocols for bioassay samples

    SciTech Connect

    MacLellan, J.A.; McFadden, K.M.

    1992-11-01

    In vitro radiobioassay analyses are used to measure the amount of radioactive material excreted by personnel exposed to the potential intake of radioactive material. The analytical results are then used with various metabolic models to estimate the amount of radioactive material in the subject's body and the original intake of radioactive material. Proper application of these metabolic models requires knowledge of the excretion period. It is normal practice to design the bioassay program based on a 24-hour excretion sample. The Hanford bioassay program simulates a total 24-hour urine excretion sample with urine collection periods lasting from one-half hour before retiring to one-half hour after rising on two consecutive days. Urine passed during the specified periods is collected in three 1-L bottles. Because the daily excretion volume given in Publication 23 of the International Commission on Radiological Protection (ICRP 1975, p. 354) for Reference Man is 1.4 L, it was proposed to use only two 1-L bottles as a cost-saving measure. This raised the broader question of what should be the design capacity of a 24-hour urine sample kit.

  16. Sampling diffusive transition paths

    SciTech Connect

    F. Miller III, Thomas; Predescu, Cristian

    2006-10-12

    We address the problem of sampling double-ended diffusive paths. The ensemble of paths is expressed using a symmetric version of the Onsager-Machlup formula, which only requires evaluation of the force field and which, upon direct time discretization, gives rise to a symmetric integrator that is accurate to second order. Efficiently sampling this ensemble requires avoiding the well-known stiffness problem associated with sampling infinitesimal Brownian increments of the path, as well as a different type of stiffness associated with sampling the coarse features of long paths. The fine-features sampling stiffness is eliminated with the use of the fast sampling algorithm (FSA), and the coarse-feature sampling stiffness is avoided by introducing the sliding and sampling (S&S) algorithm. A key feature of the S&S algorithm is that it enables massively parallel computers to sample diffusive trajectories that are long in time. We use the algorithm to sample the transition path ensemble for the structural interconversion of the 38-atom Lennard-Jones cluster at low temperature.

  17. Sampling in Qualitative Research

    PubMed Central

    LUBORSKY, MARK R.; RUBINSTEIN, ROBERT L.

    2011-01-01

    In gerontology the most recognized and elaborate discourse about sampling is generally thought to be in quantitative research associated with survey research and medical research. But sampling has long been a central concern in the social and humanistic inquiry, albeit in a different guise suited to the different goals. There is a need for more explicit discussion of qualitative sampling issues. This article will outline the guiding principles and rationales, features, and practices of sampling in qualitative research. It then describes common questions about sampling in qualitative research. In conclusion it proposes the concept of qualitative clarity as a set of principles (analogous to statistical power) to guide assessments of qualitative sampling in a particular study or proposal. PMID:22058580

  18. Sampling functions for geophysics

    NASA Technical Reports Server (NTRS)

    Giacaglia, G. E. O.; Lunquist, C. A.

    1972-01-01

    A set of spherical sampling functions is defined such that they are related to spherical-harmonic functions in the same way that the sampling functions of information theory are related to sine and cosine functions. An orderly distribution of (N + 1) squared sampling points on a sphere is given, for which the (N + 1) squared spherical sampling functions span the same linear manifold as do the spherical-harmonic functions through degree N. The transformations between the spherical sampling functions and the spherical-harmonic functions are given by recurrence relations. The spherical sampling functions of two arguments are extended to three arguments and to nonspherical reference surfaces. Typical applications of this formalism to geophysical topics are sketched.

  19. Drug sampling in dermatology.

    PubMed

    Reid, Erika E; Alikhan, Ali; Brodell, Robert T

    2012-01-01

    The use of drug samples in a dermatology clinic is controversial. Drug samples are associated with influencing physician prescribing patterns often toward costlier drugs, increasing health care costs, increasing waste, inducing potential conflicts of interest, and decreasing the quality of patient education. On the other hand, they have the potential to help those in financial need, to improve adherence and convenience, and to expose patients to better drugs. Although some academic centers have banned drug samples altogether, many academic and private practices continue to distribute drug samples. Given the controversy of the topic, physicians who wish to distribute drug samples must do so in an ethical manner. We believe, when handled properly, drug sampling can be used in an ethical manner. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Fluid sampling device

    NASA Technical Reports Server (NTRS)

    Studenick, D. K. (Inventor)

    1977-01-01

    An inlet leak is described for sampling gases, more specifically, for selectively sampling multiple fluids. This fluid sampling device includes a support frame. A plurality of fluid inlet devices extend through the support frame and each of the fluid inlet devices include a longitudinal aperture. An opening device that is responsive to a control signal selectively opens the aperture to allow fluid passage. A closing device that is responsive to another control signal selectively closes the aperture for terminating further fluid flow.

  1. Sample positioning in microgravity

    NASA Technical Reports Server (NTRS)

    Sridharan, Govind (Inventor)

    1991-01-01

    Repulsion forces arising from laser beams are provided to produce mild positioning forces on a sample in microgravity vacuum environments. The system of the preferred embodiment positions samples using a plurality of pulsed lasers providing opposing repulsion forces. The lasers are positioned around the periphery of a confinement area and expanded to create a confinement zone. The grouped laser configuration, in coordination with position sensing devices, creates a feedback servo whereby stable position control of a sample within microgravity environment can be achieved.

  2. Immune Blood Sample Draw

    NASA Image and Video Library

    2012-04-26

    ISS030-E-257690 (26 April 2012) --- European Space Agency astronaut Andre Kuipers, Expedition 30 flight engineer, prepares for IMMUNE venous blood sample draws in the Columbus laboratory of the International Space Station. Following the blood draws, the samples were temporarily stowed in the Minus Eighty Laboratory Freezer for ISS 1 (MELFI-1) and later packed together with saliva samples on the Soyuz TMA-22 for return to Earth for analysis.

  3. Aerosol Sampling Models Survey

    DTIC Science & Technology

    1993-03-01

    Particle Sizes ) for Inlet Region of Aerosol Sampling Train .......... ................ .. 49 8 Model Efficiency Calculations (Polydispersed Particle ...0 As the MMAD particle size increases, the sampling efficiency decreases. As the flow rate increases, the sampling efficiency decreases. However, the...70 93.9 88.0 N/A 7. 5 900 130 99.5 99.2 N/A 8 . 15 900 130 94.4 93.2 N/A Table 10. Model Efficiency Calculations (Polydispersed Particle Sizes ) for

  4. LUNAR SAMPLES - APOLLO 11

    NASA Image and Video Library

    1969-08-03

    S69-40749 (July 1969) --- Dr. Grant Heikan, MSC and a Lunar Sample Preliminary Examination Team member, examines lunar material in a sieve from the bulk sample container which was opened in the Biopreparation Laboratory of the Lunar Receiving Laboratory. The samples were collected by astronauts Neil A. Armstrong and Edwin E. Aldrin Jr. during their lunar surface extravehicular activity on July 20, 1969.

  5. Sample positioning in microgravity

    NASA Technical Reports Server (NTRS)

    Sridharan, Govind (Inventor)

    1993-01-01

    Repulsion forces arising from laser beams are provided to produce mild positioning forces on a sample in microgravity vacuum environments. The system of the preferred embodiment positions samples using a plurality of pulsed lasers providing opposing repulsion forces. The lasers are positioned around the periphery of a confinement area and expanded to create a confinement zone. The grouped laser configuration, in coordination with position sensing devices, creates a feedback servo whereby stable position control of a sample within microgravity environment can be achieved.

  6. Statistical distribution sampling

    NASA Technical Reports Server (NTRS)

    Johnson, E. S.

    1975-01-01

    Determining the distribution of statistics by sampling was investigated. Characteristic functions, the quadratic regression problem, and the differential equations for the characteristic functions are analyzed.

  7. Improved yield of minimal proportional sample volume platelet bacterial culture.

    PubMed

    Kamel, Hany; Townsend, Mary; Bravo, Marjorie; Vassallo, Ralph R

    2017-10-01

    Reports of septic transfusion reactions (STRs) after transfusion of culture-negative platelets (PLTs) justify more effective prevention strategies. Pathogen reduction technologies or performance of additional point-of-issue testing are proposed strategies to enhance safety through Day 5 of storage. Trima leukoreduced apheresis PLTs (APs) were collected during two study periods (45 and 31 months) using standard procedures, with target settings adjusted during the second period to maintain split rate after increased culture volume. Primary testing for bacterial contamination was performed using BacT/ALERT 3D with sampling from the mother bag 24 to 36 hours after collection. Two culture approaches were compared: in Period A, an 8-mL sample in one aerobic culture bottle (CB), and in Period B a minimal proportional sample volume (PSV) of at least 3.8% of mother bag volume into one to three aerobic CBs (7-10 mL per bottle). In Periods A and B, 188,389 and 159,098 AP collections were tested, respectively. The true-positive (TP) rate in Period A was 0.90 per 10,000 collections and in Period B was 1.83 per 10,000 (p < 0.05). In Period B, 12 of 29 (41%) TP results had discrepant CB results (DCBRs; at least one of multiple bottles without growth). The false-positive rate in Period B, 15.05 per 10,000 collections, was significantly higher than that of Period A, 3.66 per 10,000. One contaminated collection resulting in STR(s) was reported in each study period. Implementation of PSV was operationally successful and did not impact the AP split rate. Proportional sample volume improved the sensitivity of primary testing and identified collections that could have escaped detection had only a single bottle with 8- to 10-mL volume been used. PSV may represent another approach to enhanced PLT safety for 5-day storage without a requirement for secondary testing. © 2017 AABB.

  8. Urine sample (image)

    MedlinePlus

    A "clean-catch" urine sample is performed by collecting the sample of urine in midstream. Men or boys should wipe clean the head ... water and rinse well. A small amount of urine should initially fall into the toilet bowl before ...

  9. Implementing Teacher Work Sampling

    ERIC Educational Resources Information Center

    Kinne, Lenore J.; Watson, Dwight C.

    2005-01-01

    This article describes how the teacher work sample methodology of the Renaissance Partnership for Improving Teacher Quality was implemented within the teacher education program at a small liberal arts college. Resulting program improvements are described, as well as on-going challenges. The adapted teacher work sample prompt and scoring rubric are…

  10. Extraterrestrial Samples at JSC

    NASA Technical Reports Server (NTRS)

    Allen, Carlton C.

    2007-01-01

    A viewgraph presentation on the curation of extraterrestrial samples at NASA Johnson Space Center is shown. The topics include: 1) Apollo lunar samples; 2) Meteorites from Antarctica; 3) Cosmic dust from the stratosphere; 4) Genesis solar wind ions; 5) Stardust comet and interstellar grains; and 5) Space-Exposed Hardware.

  11. Lifting Sample Return Capsule

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Stardust sample return capsule successfully landed at the U.S. Air Force Utah Test and Training Range at 2:10 a.m. Pacific time (3:10 a.m. Mountain time). The capsule contains cometary and interstellar samples gathered by the Stardust spacecraft.

    Here, the capsule is being lifted at the landing site.

  12. Sample Return Capsule

    NASA Technical Reports Server (NTRS)

    2006-01-01

    NASA's Stardust sample return capsule successfully landed at the U.S. Air Force Utah Test and Training Range at 2:10 a.m. Pacific time (3:10 a.m. Mountain time). The capsule contains cometary and interstellar samples gathered by the Stardust spacecraft.

  13. Sampling system and method

    DOEpatents

    Decker, David L.; Lyles, Brad F.; Purcell, Richard G.; Hershey, Ronald Lee

    2013-04-16

    The present disclosure provides an apparatus and method for coupling conduit segments together. A first pump obtains a sample and transmits it through a first conduit to a reservoir accessible by a second pump. The second pump further conducts the sample from the reservoir through a second conduit.

  14. Microbiological surface sampling cart

    NASA Technical Reports Server (NTRS)

    Wilkins, J. R.; Mills, S. M.

    1972-01-01

    Mobile sampling cart automatically swabs surfaces for the recovery of microorganisms. Unit operates without human involvement and provides for control of swabbing speed, rotation of cotton swab, and the pressure and angle applied to swab. Capability of reverse direction is also available. Sampling cart use is limited to flat surfaces.

  15. Simple street tree sampling

    Treesearch

    David J. Nowak; Jeffrey T. Walton; James Baldwin; Jerry. Bond

    2015-01-01

    Information on street trees is critical for management of this important resource. Sampling of street tree populations provides an efficient means to obtain street tree population information. Long-term repeat measures of street tree samples supply additional information on street tree changes and can be used to report damages from catastrophic events. Analyses of...

  16. Automotive Work Sample.

    ERIC Educational Resources Information Center

    Shawsheen Valley Regional Vocational-Technical High School, Billerica, MA.

    This manual contains a work sample intended to assess a handicapped student's interest in and potential to pass successfully a training program in automotive mechanics or in a similar automotive job. Section 1 describes the assessment, correlates the work performed and worker traits required for completing the work sample, and lists related…

  17. Electronics Assembly Work Sample.

    ERIC Educational Resources Information Center

    Shawsheen Valley Regional Vocational-Technical High School, Billerica, MA.

    This manual contains a work sample intended to assess a handicapped student's interest in and potential to enter a training program in electronics assembly or in a similar program. Section 1 describes the assessment, correlates the work performed and worker traits required for completing the work sample, and lists related occupations and DOT…

  18. SWAB Air sampling

    NASA Image and Video Library

    2006-12-08

    ISS014-E-09425 (8 Dec. 2006) --- European Space Agency (ESA) astronaut Thomas Reiter, Expedition 14 flight engineer, conducts a Surface, Water and Air Biocharacterization (SWAB) air sampling in the Destiny laboratory of the International Space Station. Reiter holds a pair of scissors and the SWAB Air Sampling Device (ASD) floats freely near him.

  19. National Sample Assessment Protocols

    ERIC Educational Resources Information Center

    Ministerial Council on Education, Employment, Training and Youth Affairs (NJ1), 2012

    2012-01-01

    These protocols represent a working guide for planning and implementing national sample assessments in connection with the national Key Performance Measures (KPMs). The protocols are intended for agencies involved in planning or conducting national sample assessments and personnel responsible for administering associated tenders or contracts,…

  20. Biological sample collector

    DOEpatents

    Murphy, Gloria A [French Camp, CA

    2010-09-07

    A biological sample collector is adapted to a collect several biological samples in a plurality of filter wells. A biological sample collector may comprise a manifold plate for mounting a filter plate thereon, the filter plate having a plurality of filter wells therein; a hollow slider for engaging and positioning a tube that slides therethrough; and a slide case within which the hollow slider travels to allow the tube to be aligned with a selected filter well of the plurality of filter wells, wherein when the tube is aligned with the selected filter well, the tube is pushed through the hollow slider and into the selected filter well to sealingly engage the selected filter well and to allow the tube to deposit a biological sample onto a filter in the bottom of the selected filter well. The biological sample collector may be portable.

  1. Rapid Active Sampling Package

    NASA Technical Reports Server (NTRS)

    Peters, Gregory

    2010-01-01

    A field-deployable, battery-powered Rapid Active Sampling Package (RASP), originally designed for sampling strong materials during lunar and planetary missions, shows strong utility for terrestrial geological use. The technology is proving to be simple and effective for sampling and processing materials of strength. Although this originally was intended for planetary and lunar applications, the RASP is very useful as a powered hand tool for geologists and the mining industry to quickly sample and process rocks in the field on Earth. The RASP allows geologists to surgically acquire samples of rock for later laboratory analysis. This tool, roughly the size of a wrench, allows the user to cut away swaths of weathering rinds, revealing pristine rock surfaces for observation and subsequent sampling with the same tool. RASPing deeper (.3.5 cm) exposes single rock strata in-situ. Where a geologist fs hammer can only expose unweathered layers of rock, the RASP can do the same, and then has the added ability to capture and process samples into powder with particle sizes less than 150 microns, making it easier for XRD/XRF (x-ray diffraction/x-ray fluorescence). The tool uses a rotating rasp bit (or two counter-rotating bits) that resides inside or above the catch container. The container has an open slot to allow the bit to extend outside the container and to allow cuttings to enter and be caught. When the slot and rasp bit are in contact with a substrate, the bit is plunged into it in a matter of seconds to reach pristine rock. A user in the field may sample a rock multiple times at multiple depths in minutes, instead of having to cut out huge, heavy rock samples for transport back to a lab for analysis. Because of the speed and accuracy of the RASP, hundreds of samples can be taken in one day. RASP-acquired samples are small and easily carried. A user can characterize more area in less time than by using conventional methods. The field-deployable RASP used a Ni

  2. PFP Wastewater Sampling Facility

    SciTech Connect

    Hirzel, D.R.

    1995-05-11

    This test report documents the results obtained while conducting operational testing of the sampling equipment in the 225-WC building, the PFP Wastewater Sampling Facility. The Wastewater Sampling Facility houses equipment to sample and monitor the PFP`s liquid effluents before discharging the stream to the 200 Area Treated Effluent Disposal Facility (TEDF). The majority of the streams are not radioactive and discharges from the PFP Heating, Ventilation, and Air Conditioning (HVAC). The streams that might be contaminated are processed through the Low Level Waste Treatment Facility (LLWTF) before discharging to TEDF. The sampling equipment consists of two flow-proportional composite samplers, an ultrasonic flowmeter, pH and conductivity monitors, chart recorder, and associated relays and current isolators to interconnect the equipment to allow proper operation. Data signals from the monitors are received in the 234-5Z Shift Office which contains a chart recorder and alarm annunciator panel. The data signals are also duplicated and sent to the TEDF control room through the Local Control Unit (LCU). Performing the OTP has verified the operability of the PFP wastewater sampling system. This Operability Test Report documents the acceptance of the sampling system for use.

  3. Waste classification sampling plan

    SciTech Connect

    Landsman, S.D.

    1998-05-27

    The purpose of this sampling is to explain the method used to collect and analyze data necessary to verify and/or determine the radionuclide content of the B-Cell decontamination and decommissioning waste stream so that the correct waste classification for the waste stream can be made, and to collect samples for studies of decontamination methods that could be used to remove fixed contamination present on the waste. The scope of this plan is to establish the technical basis for collecting samples and compiling quantitative data on the radioactive constituents present in waste generated during deactivation activities in B-Cell. Sampling and radioisotopic analysis will be performed on the fixed layers of contamination present on structural material and internal surfaces of process piping and tanks. In addition, dose rate measurements on existing waste material will be performed to determine the fraction of dose rate attributable to both removable and fixed contamination. Samples will also be collected to support studies of decontamination methods that are effective in removing the fixed contamination present on the waste. Sampling performed under this plan will meet criteria established in BNF-2596, Data Quality Objectives for the B-Cell Waste Stream Classification Sampling, J. M. Barnett, May 1998.

  4. Instructions for borehole sampling

    SciTech Connect

    Reynolds, K.D.; Lindsey, K.A.

    1994-11-11

    Geologic systems generally are complex with physical properties and trends that can be difficult to predict. Subsurface geology exerts a fundamental control on groundwater flow and contaminant transport. The primary source for direct observation of subsurface geologic information is a borehole. However, direct observations from a borehole essentially are limited to the diameter and spacing of boreholes and the quality of the information derived from the drilling. Because it is impractical to drill a borehole every few feet to obtain data, it is necessary to maximize the data gathered during limited drilling operations. A technically defensible balance between the customer`s data quality objectives and control of drilling costs through limited drilling can be achieved with proper conduct of operations. This report presents the minimum criteria for geologic and hydrologic characterization and sampling that must be met during drilling. It outlines the sampling goals that need to be addressed when drilling boreholes, and the types of drilling techniques that work best to achieve these goals under the geologic conditions found at Hanford. This report provides general guidelines for: (1) how sampling methods are controlled by data needs, (2) how minimum sampling requirements change as knowledge and needs change, and (3) when drilling and sampling parameters need to be closely controlled with respect to the specific data needs. Consequently, the report is divided into two sections that center on: (1) a discussion of basic categories of subsurface characterization, sampling, and sampling techniques, and (2) guidelines for determining which drilling and sampling techniques meet required characterization and sampling objectives.

  5. Sample quality criteria.

    PubMed

    Ramsey, Charles A; Wagner, Claas

    2015-01-01

    The concept of Sample Quality Criteria (SQC) is the initial step in the scientific approach to representative sampling. It includes the establishment of sampling objectives, Decision Unit (DU), and confidence. Once fully defined, these criteria serve as input, in addition to material properties, to the Theory of Sampling for developing a representative sampling protocol. The first component of the SQC establishes these questions: What is the analyte(s) of concern? What is the concentration level of interest of the analyte(s)? How will inference(s) be made from the analytical data to the DU? The second component of the SQC establishes the DU, i.e., the scale at which decisions are to be made. On a large scale, a DU could be a ship or rail car; examples for small-scale DUs are individual beans, seeds, or kernels. A well-defined DU is critical because it defines the spatial and temporal boundaries of sample collection. SQC are not limited to a single DU; they can also include multiple DUs. The third SQC component, the confidence, establishes the desired probability that a correct inference (decision) can be made. The confidence level should typically correlate to the potential consequences of an incorrect decision (e.g., health or economic). The magnitude of combined errors in the sampling, sample processing and analytical protocols determines the likelihood of an incorrect decision. Thus, controlling error to a greater extent increases the probability of a correct decision. The required confidence level directly affects the sampling effort and QC measures.

  6. Assessment of bioburden on human and animal tissues: part 2--results of testing of human tissue and qualification of a composite sample for routine bioburden determination.

    PubMed

    Kowalski, John B; Merritt, Karen; Gocke, David; Osborne, Joel

    2012-08-01

    A quantitative method was developed and validated to assess bioburden on tissue from human donors and to compare bioburden determination results to swab culture results from the same donor. An initial study with allograft tissue from 101 donors showed a wide range of bioburden levels; values from no colony-forming units (CFU) detected to >28,000 CFU were observed. Tissues from donors that had swab cultures negative for objectionable microorganisms generally had lower bioburden than tissues from donors where objectionable microorganisms were recovered by swab culturing. In a follow-up study with 1,445 donors, a wide range of bioburden levels was again observed on tissues from donors that were swab culture negative for objectionable microorganisms. Tissues from 885 (61%) of these donors had no recoverable bioburden (<2 CFU). Importantly, tissues from 560 (39%) of the donors had recoverable bioburden which ranged from 1 to >24,000 CFU. Identification of bioburden isolates showed a diversity of genera and species. In compliance with the recent revision of the American Association of Tissue Banks K2.210 Standard, the quantitative bioburden determination method was validated with a composite tissue sample that contains bone and soft tissue sections tested together in one extraction vessel. A recovery efficiency of 68% was validated and the composite sample was shown to be representative of all of the tissues recovered from a donor. The use of the composite sample in conjunction with the quantitative bioburden determination method will facilitate an accurate assessment of the numbers and types of contaminating microorganisms on allografts prior to disinfection/sterilization. This information will ensure that disinfection/sterilization processes are properly validated and the capability of the overall allograft process is understood on a donor by donor basis.

  7. Sampling video compression system

    NASA Technical Reports Server (NTRS)

    Matsumoto, Y.; Lum, H. (Inventor)

    1977-01-01

    A system for transmitting video signal of compressed bandwidth is described. The transmitting station is provided with circuitry for dividing a picture to be transmitted into a plurality of blocks containing a checkerboard pattern of picture elements. Video signals along corresponding diagonal rows of picture elements in the respective blocks are regularly sampled. A transmitter responsive to the output of the sampling circuitry is included for transmitting the sampled video signals of one frame at a reduced bandwidth over a communication channel. The receiving station is provided with a frame memory for temporarily storing transmitted video signals of one frame at the original high bandwidth frequency.

  8. Automated versus manual sample inoculations in routine clinical microbiology: a performance evaluation of the fully automated InoqulA instrument.

    PubMed

    Froment, P; Marchandin, H; Vande Perre, P; Lamy, B

    2014-03-01

    The process of plate streaking has been automated to improve the culture readings, isolation quality, and workflow of microbiology laboratories. However, instruments have not been well evaluated under routine conditions. We aimed to evaluate the performance of the fully automated InoqulA instrument (BD Kiestra B.V., The Netherlands) in the automated seeding of liquid specimens and samples collected using swabs with transport medium. We compared manual and automated methods according to the (i) within-run reproducibility using Escherichia coli-calibrated suspensions, (ii) intersample contamination using a series of alternating sterile broths and broths with >10(5) CFU/ml of either E. coli or Proteus mirabilis, (iii) isolation quality with standardized mixed bacterial suspensions of diverse complexity and a 4-category standardized scale (very poor, poor, fair to good, or excellent), and (iv) agreement of the results obtained from 244 clinical specimens. By involving 15 technicians in the latter part of the comparative study, we estimated the variability in the culture quality at the level of the laboratory team. The instrument produced satisfactory reproducibility with no sample cross-contamination, and it performed better than the manual method, with more colony types recovered and isolated (up to 11% and 17%, respectively). Finally, we showed that the instrument did not shorten the seeding time over short periods of work compared to that for the manual method. Altogether, the instrument improved the quality and standardization of the isolation, thereby contributing to a better overall workflow, shortened the time to results, and provided more accurate results for polymicrobial specimens.

  9. Soil Gas Sampling

    EPA Pesticide Factsheets

    Field Branches Quality System and Technical Procedures: This document describes general and specific procedures, methods and considerations to be used and observed when collecting soil gas samples for field screening or laboratory analysis.

  10. FIR ACE samples

    NASA Image and Video Library

    2014-06-04

    ISS040-E-007368 (5 June 2014) --- NASA astronaut Reid Wiseman, Expedition 40 flight engineer, works with Advanced Colloids Experiment (ACE) samples in the Destiny laboratory of the International Space Station.

  11. Water Sample Concentrator

    ScienceCinema

    Idaho National Laboratory

    2016-07-12

    Automated portable device that concentrates and packages a sample of suspected contaminated water for safe, efficient transport to a qualified analytical laboratory. This technology will help safeguard against pathogen contamination or chemical and biolog

  12. Sample EPA Biotech Form

    EPA Pesticide Factsheets

    This sample “EPA Biotech Form” is a header sheet that will accompany all biotechnology submission choices, including MCANs, TERAs, Tier I and Tier II exemption, and biotechnology Test Market Exemption Applications (TMEAs).

  13. Preparing Samples on Mars

    NASA Image and Video Library

    2013-02-20

    This figure shows the location of CHIMRA on the turret of NASA Curiosity rover, together with a cutaway view of the device. CHIMRA processes samples from the rover scoop or drill and delivers them to science instruments.

  14. Waste tank sample transport

    SciTech Connect

    Field, J.G.; Mercado, M.S.; Smith, R.J.; Thornton, J.W.

    1994-08-01

    Since 1943, radioactive liquid waste has been stored in underground storage tanks at the Hanford Site in Richland, Washington. The waste was the result of chemical separation processes for the production of fissile defense materials. Associated with the current environmental cleanup mission, waste characterization and processing programs are requiring the extraction of samples from the tanks. Approved onsite packaging are in place and in use for transfers of samples from the tanks to onsite laboratories. Initiatives are under way to develop and procure packaging for sample shipments to offsite laboratories. This paper will provide a current status of the tank sample packaging used at the Hanford Site, as well as the project status for new packaging to be used for offsite shipments.

  15. Water Sample Concentrator

    SciTech Connect

    Idaho National Laboratory

    2009-07-21

    Automated portable device that concentrates and packages a sample of suspected contaminated water for safe, efficient transport to a qualified analytical laboratory. This technology will help safeguard against pathogen contamination or chemical and biolog

  16. Liquid sample processor

    NASA Technical Reports Server (NTRS)

    Jahnsen, V. J.; Campen, C. F., Jr.

    1975-01-01

    Processor is automatic and includes series of extraction tubes packed with fibrous absorbent material of large surface area. When introduced into these tubes, liquid test samples become completely absorbed by packing material as thin film.

  17. Lunar sample contracts

    NASA Technical Reports Server (NTRS)

    Walker, R. M.

    1974-01-01

    The major scientific accomplishments through 1971 are reported for the particle track studies of lunar samples. Results are discussed of nuclear track measurements by optical and electron microscopy, thermoluminescence, X-ray diffraction, and differential thermal analysis.

  18. LACIE sampling design

    NASA Technical Reports Server (NTRS)

    Feiveson, A. H.; Chhikara, R. S.; Hallum, C. R. (Principal Investigator)

    1979-01-01

    The sampling design in LACIE consisted of two major components, one for wheat acreage estimation and one for wheat yield prediction. The acreage design was basically a classical survey for which the sampling unit was a 5- by 6-nautical mile segment; however, there were complications caused by measurement errors and loss of data. Yield was predicted by sampling meteorological data from weather stations within a region and then using those data as input to previously fitted regression equations. Wheat production was not estimated directly, but was computed by multiplying yield and acreage estimates. The allocation of samples to countries is discussed as well as the allocation and selection of segments in strata/substrata.

  19. SWAB Air sampling

    NASA Image and Video Library

    2006-12-08

    ISS014-E-09422 (8 Dec. 2006) --- European Space Agency (ESA) astronaut Thomas Reiter, Expedition 14 flight engineer, conducts a Surface, Water and Air Biocharacterization (SWAB) air sampling in the Destiny laboratory of the International Space Station.

  20. [Foetal sampling techniques].

    PubMed

    Levy, R; Arfi, J-S; Daffos, F

    2003-06-01

    This article describes the current techniques of foetal sampling. All of them are actually ultrasound guided, and therefore generally very safe. Nevertheless, an elaborate learning process remains indispensable, in addition to a particular attention to the quality of the physician-patient dialogue. The choice of a technique depends on the indication and on the term of the pregnancy. The most frequently used technique is amniocentesis which presents a low risk of foetal loss, estimated between 0.2 and 0.5 percent. The interest of chorionic villus sampling is the possibility to obtain results at an earlier stage of pregnancy, with a lower risk taking when compared to early amniocentesis. We prefer the transabdominal chorionic villus sampling to the transvaginal. Foetal blood sampling is still required in some cases, but the risk of complications is higher--around 1 percent.

  1. Sealed container sampling device

    NASA Technical Reports Server (NTRS)

    Hennigan, T. J.

    1969-01-01

    Sampling device, by means of a tapered needle, pierces a sealed container while maintaining the seal and either evacuates or pressurizes the container. This device has many applications in the chemical, preservative and battery-manufacturing industries.

  2. Open port sampling interface

    DOEpatents

    Van Berkel, Gary J

    2017-04-25

    A system for sampling a sample material includes a probe which can have an outer probe housing with an open end. A liquid supply conduit within the housing has an outlet positioned to deliver liquid to the open end of the housing. The liquid supply conduit can be connectable to a liquid supply for delivering liquid at a first volumetric flow rate to the open end of the housing. A liquid exhaust conduit within the housing is provided for removing liquid from the open end of the housing. A liquid exhaust system can be provided for removing liquid from the liquid exhaust conduit at a second volumetric flow rate, the first volumetric flow rate exceeding the second volumetric flow rate, wherein liquid at the open end will receive sample, liquid containing sample material will be drawn into and through the liquid exhaust conduit, and liquid will overflow from the open end.

  3. Sample positioning apparatus

    DOEpatents

    Bell, Thomas H.; Johnson, Jr., Charles H.; Lane, Robert L.; Martin, Bradley E.; Tyree, William H.

    1976-01-06

    Apparatus for use in alpha particle counting with such as photomultiplier tubes, comprising a platform and linkage mechanism whereby samples are moved in linear manner toward and away from ends of the photomultiplier tubes.

  4. SAMPLING AND ANALYSIS PROTOCOLS

    SciTech Connect

    Jannik, T; P Fledderman, P

    2007-02-09

    Radiological sampling and analyses are performed to collect data for a variety of specific reasons covering a wide range of projects. These activities include: Effluent monitoring; Environmental surveillance; Emergency response; Routine ambient monitoring; Background assessments; Nuclear license termination; Remediation; Deactivation and decommissioning (D&D); and Waste management. In this chapter, effluent monitoring and environmental surveillance programs at nuclear operating facilities and radiological sampling and analysis plans for remediation and D&D activities will be discussed.

  5. TANK 5 SAMPLING

    SciTech Connect

    Vrettos, N; William Cheng, W; Thomas Nance, T

    2007-11-26

    Tank 5 at the Savannah River Site has been used to store high level waste and is currently undergoing waste removal processes in preparation for tank closure. Samples were taken from two locations to determine the contents in support of Documented Safety Analysis (DSA) development for chemical cleaning. These samples were obtained through the use of the Drop Core Sampler and the Snowbank Sampler developed by the Engineered Equipment & Systems (EES) group of the Savannah River National Laboratory (SRNL).

  6. Dissolution actuated sample container

    SciTech Connect

    Nance, Thomas A.; McCoy, Frank T.

    2013-03-26

    A sample collection vial and process of using a vial is provided. The sample collection vial has an opening secured by a dissolvable plug. When dissolved, liquids may enter into the interior of the collection vial passing along one or more edges of a dissolvable blocking member. As the blocking member is dissolved, a spring actuated closure is directed towards the opening of the vial which, when engaged, secures the vial contents against loss or contamination.

  7. Lunar Sample Compendium

    NASA Technical Reports Server (NTRS)

    Meyer, Charles

    2005-01-01

    The purpose of the Lunar Sample Compendium will be to inform scientists, astronauts and the public about the various lunar samples that have been returned from the Moon. This Compendium will be organized rock by rock in the manor of a catalog, but will not be as comprehensive, nor as complete, as the various lunar sample catalogs that are available. Likewise, this Compendium will not duplicate the various excellent books and reviews on the subject of lunar samples (Cadogen 1981, Heiken et al. 1991, Papike et al. 1998, Warren 2003, Eugster 2003). However, it is thought that an online Compendium, such as this, will prove useful to scientists proposing to study individual lunar samples and should help provide backup information for lunar sample displays. This Compendium will allow easy access to the scientific literature by briefly summarizing the significant findings of each rock along with the documentation of where the detailed scientific data are to be found. In general, discussion and interpretation of the results is left to the formal reviews found in the scientific literature. An advantage of this Compendium will be that it can be updated, expanded and corrected as need be.

  8. Lunar Samples - Apollo 17

    NASA Image and Video Library

    1972-12-27

    S72-56362 (27 Dec. 1972) --- Scientist-astronaut Harrison H. "Jack" Schmitt (facing camera), Apollo 17 lunar module pilot, was one of the first to look at the sample of "orange" soil which was brought back from the Taurus-Littrow landing site by the Apollo 17 crewmen. Schmitt discovered the material at Shorty Crater during the second Apollo 17 extravehicular activity (EVA). The "orange" sample, which was opened Wednesday, Dec. 27, 1972, is in the bag on a weighing platform in the sealed nitrogen cabinet in the upstairs processing line in the Lunar Receiving Laboratory at the Manned Spacecraft Center. Just before, the sample was removed from one of the bolt-top cans visible to the left in the cabinet. The first reaction of Schmitt was "It doesn't look the same." Most of the geologists and staff viewing the sample agreed that it was more tan and brown than orange. Closer comparison with color charts showed that the sample had a definite orange cast, according the MSC geology branch Chief William Phinney. After closer investigation and sieving, it was discovered that the orange color was caused by very fine spheres and fragments of orange glass in the midst of darker colored, larger grain material. Earlier in the day the "orange" soil was taken from the Apollo Lunar Sample Return Container No. 2 and placed in the bolt-top can (as was all the material in the ALSRC "rock box").

  9. Liquid sampling system

    DOEpatents

    Larson, Loren L.

    1987-01-01

    A conduit extends from a reservoir through a sampling station and back to the reservoir in a closed loop. A jet ejector in the conduit establishes suction for withdrawing liquid from the reservoir. The conduit has a self-healing septum therein upstream of the jet ejector for receiving one end of a double-ended cannula, the other end of which is received in a serum bottle for sample collection. Gas is introduced into the conduit at a gas bleed between the sample collection bottle and the reservoir. The jet ejector evacuates gas from the conduit and the bottle and aspirates a column of liquid from the reservoir at a high rate. When the withdrawn liquid reaches the jet ejector the rate of flow therethrough reduces substantially and the gas bleed increases the pressure in the conduit for driving liquid into the sample bottle, the gas bleed forming a column of gas behind the withdrawn liquid column and interrupting the withdrawal of liquid from the reservoir. In the case of hazardous and toxic liquids, the sample bottle and the jet ejector may be isolated from the reservoir and may be further isolated from a control station containing remote manipulation means for the sample bottle and control valves for the jet ejector and gas bleed.

  10. Liquid sampling system

    DOEpatents

    Larson, L.L.

    1984-09-17

    A conduit extends from a reservoir through a sampling station and back to the reservoir in a closed loop. A jet ejector in the conduit establishes suction for withdrawing liquid from the reservoir. The conduit has a self-healing septum therein upstream of the jet ejector for receiving one end of a double-ended cannula, the other end of which is received in a serum bottle for sample collection. Gas is introduced into the conduit at a gas bleed between the sample collection bottle and the reservoir. The jet ejector evacuates gas from the conduit and the bottle and aspirates a column of liquid from the reservoir at a high rate. When the withdrawn liquid reaches the jet ejector the rate of flow therethrough reduces substantially and the gas bleed increases the pressure in the conduit for driving liquid into the sample bottle, the gas bleed forming a column of gas behind the withdrawn liquid column and interrupting the withdrawal of liquid from the reservoir. In the case of hazardous and toxic liquids, the sample bottle and the jet ejector may be isolated from the reservoir and may be further isolated from a control station containing remote manipulation means for the sample bottle and control valves for the jet ejector and gas bleed. 5 figs.

  11. Recommended protocols for sampling macrofungi

    Treesearch

    Gregory M. Mueller; John Paul Schmit; Sabine M. Hubndorf Leif Ryvarden; Thomas E. O' Dell; D. Jean Lodge; Patrick R. Leacock; Milagro Mata; Loengrin Umania; Qiuxin (Florence) Wu; Daniel L. Czederpiltz

    2004-01-01

    This chapter discusses several issues regarding reommended protocols for sampling macrofungi: Opportunistic sampling of macrofungi, sampling conspicuous macrofungi using fixed-size, sampling small Ascomycetes using microplots, and sampling a fixed number of downed logs.

  12. Sample Return Science

    NASA Astrophysics Data System (ADS)

    Williford, K. H.; Allwood, A.; Beegle, L. W.; Bhartia, R.; Flannery, D.; Hoffmann, A.; Mora, M. F.; Orbay, J.; Petrizzo, D. A.; Tuite, M. L., Jr.; Willis, P. A.

    2014-12-01

    The first clear identification of an ancient habitable environment on Mars by the Mars Science Laboratory (MSL) rover mission relied on a synthetic analytical approach combining orbital and surface imagery and spectroscopy with sophisticated sample acquisition and handling technology including a rotary percussive drill that provided powdered rock for bulk geochemical analysis [1]. The recent announcement of the instrument package for the proposed NASA Mars2020 rover mission, including micro x-ray fluorescence (PIXL) for elemental mapping as well as scanning ultraviolet laser fluorescence and Raman (SHERLOC) suggests a shift in emphasis of Mars surface science towards spatially resolved geochemical analysis that will support the selection and acquisition of samples for coring, caching, and possible return to Earth for further analysis. During a recent field expedition to investigate Archean and Proterozoic biosignatures in the Pilbara region of Western Australia, we deployed a dry, rotary percussive coring drill with a bit assembly analogous to that being considered for Mars2020. Six targets of varying age and lithology were sampled with the coring drill, and surrounding and adjacent rock samples were collected simultaneously. These samples were subsequently prepared and subsampled for bulk and in situ, spatially resolved analysis using conventional laboratory methods as well as the existing PIXL and SHERLOC platforms currently in development. Here we present new approaches and data from this integrated and ongoing program of "sample return science" designed to simulate, and eventually reduce risk associated with a long-term effort towards Mars sample return. [1] Grotzinger, J.P. et al. 2014. Science 343 DOI: 10.1126/science.1242777.

  13. Deconvolution with Correct Sampling

    NASA Astrophysics Data System (ADS)

    Magain, P.; Courbin, F.; Sohy, S.

    1998-02-01

    A new method for improving the resolution of astronomical images is presented. It is based on the principle that sampled data cannot be fully deconvolved without violating the sampling theorem. Thus, the sampled image should be deconvolved not by the total point-spread function but by a narrower function chosen so that the resolution of the deconvolved image is compatible with the adopted sampling. Our deconvolution method gives results that are, in at least some cases, superior to those of other commonly used techniques: in particular, it does not produce ringing around point sources superposed on a smooth background. Moreover, it allows researchers to perform accurate astrometry and photometry of crowded fields. These improvements are a consequence of both the correct treatment of sampling and the recognition that the most probable astronomical image is not a flat one. The method is also well adapted to the optimal combination of different images of the same object, as can be obtained, e.g., from infrared observations or via adaptive optics techniques.

  14. Fluid sampling system

    DOEpatents

    Houck, E.D.

    1994-10-11

    An fluid sampling system allows sampling of radioactive liquid without spillage. A feed tank is connected to a liquid transfer jet powered by a pumping chamber pressurized by compressed air. The liquid is pumped upwardly into a sampling jet of a venturi design having a lumen with an inlet, an outlet, a constricted middle portion, and a port located above the constricted middle portion. The liquid is passed under pressure through the constricted portion causing its velocity to increase and its pressure to be decreased, thereby preventing liquid from escaping. A septum sealing the port can be pierced by a two pointed hollow needle leading into a sample bottle also sealed by a pierceable septum affixed to one end. The bottle is evacuated by flow through the sample jet, cyclic variation in the sampler jet pressure periodically leaves the evacuated bottle with lower pressure than that of the port, thus causing solution to pass into the bottle. The remaining solution in the system is returned to the feed tank via a holding tank. 4 figs.

  15. Fluid sampling system

    DOEpatents

    Houck, Edward D.

    1994-01-01

    An fluid sampling system allows sampling of radioactive liquid without spillage. A feed tank is connected to a liquid transfer jet powered by a pumping chamber pressurized by compressed air. The liquid is pumped upwardly into a sampling jet of a venturi design having a lumen with an inlet, an outlet, a constricted middle portion, and a port located above the constricted middle portion. The liquid is passed under pressure through the constricted portion causing its velocity to increase and its pressure to decreased, thereby preventing liquid from escaping. A septum sealing the port can be pierced by a two pointed hollow needle leading into a sample bottle also sealed by a pierceable septum affixed to one end. The bottle is evacuated by flow through the sample jet, cyclic variation in the sampler jet pressure periodically leaves the evacuated bottle with lower pressure than that of the port, thus causing solution to pass into the bottle. The remaining solution in the system is returned to the feed tank via a holding tank.

  16. Fluid sampling system

    SciTech Connect

    Houck, E.D.

    1993-12-31

    This invention comprises a fluid sampling system which allows sampling of radioactive liquid without spillage. A feed tank is connected to a liquid transfer jet powered by a pumping chamber pressurized by compressed air. The liquid is pumped up into a sampling jet of venturi design having a lumen with an inlet, an outlet, a constricted middle portion, and a port located above the constricted middle portion. The liquid is passed under pressure through the constricted portion causing its velocity to increase and its pressure to decrease, thereby preventing liquid from escaping. A septum sealing the port can be pierced by a two pointed hollow needle leading into a sample bottle also sealed by a pierceable septum affixed to one end. The bottle is evacuated by flow through the sample jet, cyclic variation in the sampler jet pressure periodicially leaves the evacuated bottle with lower pressure than that of the port, thus causing solution to pass into the bottle. The remaining solution in the system is returned to the feed tank via a holding tank.

  17. Comparison of polymerase chain reaction and bacteriological culture for the diagnosis of sheep brucellosis using aborted fetus samples.

    PubMed

    Leyla, Güler; Kadri, Gündüz; Umran, Ok

    2003-05-02

    PCR assay has been shown to be a promising option for the diagnosis of brucellosis. However, few studies have been performed with field samples in order to evaluate the assay as a diagnostic tool. In this study, routine use of a species-specific PCR assay previously developed for the identification of Brucella cultures was assessed for the detection of Brucella DNA directly from the stomach contents of aborted sheep fetuses. The assay is based on the insertion sequence IS711 in the Brucella chromosome. In the study, during 3 successive lambing seasons (1998-1999, 1999-2000 and 2000-2001) 126 aborted fetus samples each from different flocks and locations were examined. Brucella strains were isolated from 39 (31%) of the samples and all of the strains were identified as Brucella melitensis by biochemical characteristics, agglutination with monospecific A and M sera and PCR. Thirty-seven of 39 B. melitensis isolates were biotyped as biotype 3, and 2 isolates as biotype 1. From 38 of 39 culture positive fetal stomach contents B. melitensis-specific DNA was detected by PCR. PCR was found negative in all of the culture negative samples. Compared with culture, sensitivity and specificity of PCR were determined as 97.4 and 100%, respectively. The results indicate that this PCR procedure has a potential for use in routine diagnosis of sheep brucellosis.

  18. Thermoluminescence of lunar samples

    USGS Publications Warehouse

    Dalrymple, G.B.; Doell, Richard R.

    1970-01-01

    Appreciable natural thermoluminescence with glow curve peaks at about 350 degrees centigrade for lunar fines and breccias and above 400 degrees centigrade for crystalline rocks has been recognized in lunar samples. Plagioclase has been identified as the principal carrier of thermoluminescence, and the difference in peak temperatures indicates compositional or structural differences between the feldspars of the different rock types. The present thermoluminescence in the lunar samples is probably the result of a dynamic equilibrium between acquisition from radiation and loss in the lunar thermal environment. A progressive change in the glow curves of core samples with depth below the surface suggests the use of thermoluminescence disequilibrium to detect surfaces buried by recent surface activity, and it also indicates that the lunar diurnal temperature variation penetrates to at least 10.5 centimeters.

  19. Sampling inhomogeneous turbulent fields

    NASA Technical Reports Server (NTRS)

    Adrian, R. J.; Moin, P.; Moser, R. D.

    1988-01-01

    The reconstruction of an inhomogeneous random process from a finite number of discrete samples can be performed in terms of the Karhunen-Loeve (KL) expansion for that process. The n(th) eigenfunction has n - 1 zero crossings which are the sampling points for the inhomogeneous process. The rapid variation of the KL eigenfunctions makes it unnecessary to have a high density of sampling (or grid points) near the wall. However, this result should not be construed to indicate that with spectral simulations significantly fewer grid points are required with the KL expansion as compared to other orthogonal expansions. Moin and Moser (1989) have shown that the advantage of the KL expansion over Chebychev expansion rapidly diminishes when high percentage (say 90 percent) energy recovery is demanded.

  20. INEL Sample Management Office

    SciTech Connect

    Watkins, C.

    1994-12-31

    The Idaho National Engineering Laboratory (INEL) Sample Management Office (SMO) was formed as part of the EG&G Idaho Environmental Restoration Program (ERP) in June, 1990. Since then, the SMO has been recognized and sought out by other prime contractors and programs at the INEL. Since December 1991, the DOE-ID Division Directors for the Environmental Restoration Division and Waste Management Division supported the expansion of the INEL ERP SMO into the INEL site wide SMO. The INEL SMO serves as a point of contact for multiple environmental analytical chemistry and laboratory issues (e.g., capacity, capability). The SMO chemists work with project managers during planning to help develop data quality objectives, select appropriate analytical methods, identify special analytical services needs, identify a source for the services, and ensure that requirements for sampling and analysis (e.g., preservations, sample volumes) are clear and technically accurate. The SMO chemists also prepare work scope statements for the laboratories performing the analyses.

  1. Viscous sludge sample collector

    DOEpatents

    Beitel, George A [Richland, WA

    1983-01-01

    A vertical core sample collection system for viscous sludge. A sample tube's upper end has a flange and is attached to a piston. The tube and piston are located in the upper end of a bore in a housing. The bore's lower end leads outside the housing and has an inwardly extending rim. Compressed gas, from a storage cylinder, is quickly introduced into the bore's upper end to rapidly accelerate the piston and tube down the bore. The lower end of the tube has a high sludge entering velocity to obtain a full-length sludge sample without disturbing strata detail. The tube's downward motion is stopped when its upper end flange impacts against the bore's lower end inwardly extending rim.

  2. Experimental scattershot boson sampling

    PubMed Central

    Bentivegna, Marco; Spagnolo, Nicolò; Vitelli, Chiara; Flamini, Fulvio; Viggianiello, Niko; Latmiral, Ludovico; Mataloni, Paolo; Brod, Daniel J.; Galvão, Ernesto F.; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto; Sciarrino, Fabio

    2015-01-01

    Boson sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialized quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, scattershot boson sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric down-conversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. We report the first scattershot boson sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We use recently proposed statistical tools to analyze our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy. PMID:26601164

  3. Core sample extractor

    NASA Technical Reports Server (NTRS)

    Akins, James; Cobb, Billy; Hart, Steve; Leaptrotte, Jeff; Milhollin, James; Pernik, Mark

    1989-01-01

    The problem of retrieving and storing core samples from a hole drilled on the lunar surface is addressed. The total depth of the hole in question is 50 meters with a maximum diameter of 100 millimeters. The core sample itself has a diameter of 60 millimeters and will be two meters in length. It is therefore necessary to retrieve and store 25 core samples per hole. The design utilizes a control system that will stop the mechanism at a certain depth, a cam-linkage system that will fracture the core, and a storage system that will save and catalogue the cores to be extracted. The Rod Changer and Storage Design Group will provide the necessary tooling to get into the hole as well as to the core. The mechanical design for the cam-linkage system as well as the conceptual design of the storage device are described.

  4. [INSEE's permanent demographic sample].

    PubMed

    Sautory, O

    1987-01-01

    This article discusses the permanent demographic sample survey developed by France's Institut National de la Statistique et des Etudes Economiques (INSEE), which has been in use in that country since the census of 1968. Approximately one percent of the metropolitan population of France was chosen for inclusion by birthdate. By adding data on marriage, births of children, change of residence, schooling, employment status, and death to each person's file, longitudinal studies of fertility, nuptiality, and mortality can be conducted. Two such studies are included as examples of how the permanent sample survey can be best put to use.

  5. Contamination sampling device

    NASA Technical Reports Server (NTRS)

    Delgado, Felix A. (Inventor); Stern, Susan M. (Inventor)

    1998-01-01

    A contamination sample collection device has a wooden dowel with a cotton swab at one end, the cotton being covered by a nylon cloth and the wooden dowel being encapsulated by plastic tubing which is heat shrunk onto the dowel and onto a portion of the cotton swab to secure the cotton in place. Another plastic tube is heat shrunk onto the plastic that encapsulates the dowel and a portion of the nylon cloth to secure the nylon cloth in place. The device may thereafter be covered with aluminum foil protector. The device may be used for obtaining samples of contamination in clean room environments.

  6. diamond-sampling

    SciTech Connect

    Ballard, Grey; Kolda, Tamara; Pinar, Ali

    2016-01-26

    This software provides a means for computing only the largest few entries of the product of two matrices, both exactly and approximately (using randomized sampling techniques). The purpose of the code is to demonstrate both the time it takes to solve the problem as well as the accuracy of the approximate approach. It is also meant to serve as a foundation to test the applicability of the sampling technique to related problems in data mining, including maximum inner product search, nearest neighbor search, and maximum cosine similarity.

  7. Lunar Samples - Apollo 12

    NASA Image and Video Library

    1969-11-28

    S69-60354 (29 Nov. 1969) --- A scientist's gloved hand holds one of the numerous rock samples brought back to Earth from the Apollo 12 lunar landing mission. The rocks are under thorough examination in the Manned Spacecraft Center's (MSC) Lunar Receiving Laboratory (LRL). This sample is a highly shattered basaltic rock with a thin black-glass coating on five of its six sides. Glass fills fractures and cements the rock together. The rock appears to have been shattered and thrown out by a meteorite impact explosion and coated with molten rock material before the rock fell to the surface.

  8. Lunar Samples - Apollo 12

    NASA Image and Video Library

    1969-12-02

    S69-60580 (November 1969) --- Close-up view of Apollo 12 sample 12,065 under observation in the Manned Spacecraft Center's (MSC) Lunar Receiving Laboratory (LRL). This sample, collected during the second Apollo 12 extravehicular activity (EVA) of astronauts Charles Conrad Jr. and Alan L. Bean, is a fine-grained rock. Note the glass-lined pits. Viewer can gain an idea of the size of the rock by reference to the gauge on the bottom portion of the number meter.

  9. Rapid Dispersion of Polymicrobial Wound Biofilms with Depolymerase Enzymes

    DTIC Science & Technology

    2011-11-01

    Initially, most war wounds are colonized by Gram -positive bacteria. However, after initial stabilization and surgery, residual infections in open...wounds are characterized by predominantly Gram -negative bacteria including Acinetobacter baumannii-calcoaceticus complex, Klebsiella pneumoniae, and...identical to many of the other Gram -negative organisms, for which there are Podoviridae phage and tailspike proteins. If this is not the case, we will

  10. Enhanced Glycolytic Metabolism Contributes to Cardiac Dysfunction in Polymicrobial Sepsis.

    PubMed

    Zheng, Zhibo; Ma, He; Zhang, Xia; Tu, Fei; Wang, Xiaohui; Ha, Tuanzhu; Fan, Min; Liu, Li; Xu, Jingjing; Yu, Kaijiang; Wang, Ruitao; Kalbfleisch, John; Kao, Race; Williams, David; Li, Chuanfu

    2017-05-01

    Cardiac dysfunction is present in >40% of sepsis patients and is associated with mortality rates of up to 70%. Recent evidence suggests that glycolytic metabolism plays a critical role in host defense and inflammation. Activation of Toll-like receptors on immune cells can enhance glycolytic metabolism. This study investigated whether modulation of glycolysis by inhibition of hexokinase will be beneficial to septic cardiomyopathy. Male C57B6/J mice were treated with a hexokinase inhibitor (2-deoxy-d-glucose [2-DG], 0.25-2 g/kg, n = 6-8) before cecal ligation and puncture (CLP) induced sepsis. Untreated septic mice served as control. Sham surgically operated mice treated with or without the 2-DG inhibitor served as sham controls. Cardiac function was assessed 6 hours after CLP sepsis by echocardiography. Serum was harvested for measurement of inflammatory cytokines and lactate. Sepsis-induced cardiac dysfunction was significantly attenuated by administration of 2-DG. Ejection fraction and fractional shortening in 2-DG-treated septic mice were significantly (P < .05) greater than in untreated CLP mice. 2-DG administration also significantly improved survival outcome, reduced kidney and liver injury, attenuated sepsis-increased serum levels of tumor necrosis factor α and interleukin 1β as well as lactate, and enhanced the expression of Sirt1 and Sirt3 in the myocardium, which play an important role in mitochondrial function and metabolism. In addition, 2-DG administration suppresses sepsis-increased expression of apoptotic inducers Bak and Bax as well as JNK phosphorylation in the myocardium. Glycolytic metabolism plays an important role in mediating sepsis-induced septic cardiomyopathy. The mechanisms may involve regulation of inflammatory response and apoptotic signaling.

  11. Rapid Dispersion of Polymicrobial Wound Biofilms with Depolymerase Enzymes

    DTIC Science & Technology

    2013-11-01

    International Phage Biology Meeting. Olympia, WA. Poster. “Rapid Destruction of Biofilm Matrices by Bacteriophage-Encoded Enzymes” ( August , 2011...International Phage Biology Meeting. Olympia, WA. Symposium speaker. “Tail Spikes and Biofilm Degradation” ( August , 2013) 11. Uniformed Services...biofilms for wastewater treatment. Stockholm: Royal Institute of Technology. 22. Comte S, Guibaud G, Baudu M (2007) Effect of extraction method on EPS from

  12. Kinetics and morphology of polymicrobial biofilm formation on polypropylene mesh.

    PubMed

    Stoodley, Paul; Sidhu, Sandeep; Nistico, Laura; Mather, Megan; Boucek, Ashley; Hall-Stoodley, Luanne; Kathju, Sandeep

    2012-07-01

    We examined the ability of three clinical bacterial isolates to form mixed biofilms on surgical polypropylene mesh (PPM) in vitro. The three strains--Staphylococcus aureus, Enterococcus faecalis, and Enterobacter cloacae--were isolated from a patient with an infected PPM. Staphylococcus aureus and E. faecalis (alone and in combination) were inoculated into culture containing squares of PPM and allowed to attach and propagate into mature biofilms. Enterococcus faecalis initially attached to the mesh in greater numbers; however, 7 days postinoculation, there were more S. aureus cells attached, indicating that in vitro S. aureus is the out-competing species. All three isolates were then co-cultured to form mature biofilms on mesh, and the biofilms were examined by confocal microscopy using both Live/Dead staining and fluorescent in situ hybridization (FISH). Imaging revealed a dense biofilm structure with interstitial voids and channels; rods and cocci were interspersed throughout the biofilm, indicating bacterial coexistence in close proximity. FISH revealed staphylococci and enterococci adjacent to each other and also to the Enterobacter, distinguishable by its rod morphology. These studies show that different species can co-operatively form mature biofilms on mesh but that the relative abundance of a species within the biofilm may vary over time. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  13. Polymicrobial skull osteomyelitis: a rare complication of subdural hematoma evacuation.

    PubMed

    Calcagno, Scott W; Graves, Richard M; Baum, Sue E; Teff, Richard J

    2007-08-01

    Osteomyelitis of the skull (SO) is a rare condition. The infection may complicate community-acquired sinusitis, otitis, or mastoiditis, in which case, the skull base is affected most commonly. The flora typically seen in these conditions, such as Streptococcus pneumoniae and Haemophilus influenzae, tends also to be responsible for the SO. Osteomyelitis also may follow neurosurgical procedures that breach the skull, in which case, the pathogens frequently are typical cutaneous flora such as Staphylococcus aureus or coagulase-negative staphylococci. A case report of post-neurosurgical SO and a review of the relevant English-language literature. We report a delayed presentation of SO after craniotomy for the evacuation of a chronic subdural hematoma. Cranial tissue cultures grew Staphylococcus aureus, Corynebacterium spp., and Escherichia coli. The isolation of Escherichia coli as an infecting organism in SO has been reported rarely and may reflect a unique pathogenesis.

  14. Microbial Herd Protection Mediated by Antagonistic Interaction in Polymicrobial Communities

    PubMed Central

    Wong, Megan J. Q.; Liang, Xiaoye; Smart, Matt; Tang, Le; Moore, Richard; Ingalls, Brian

    2016-01-01

    ABSTRACT In host and natural environments, microbes often exist in complex multispecies communities. The molecular mechanisms through which such communities develop and persist, despite significant antagonistic interactions between species, are not well understood. The type VI secretion system (T6SS) is a lethal weapon commonly employed by Gram-negative bacteria to inhibit neighboring species through the delivery of toxic effectors. It is well established that intraspecies protection is conferred by immunity proteins that neutralize effector toxicities. In contrast, the mechanisms for interspecies protection are not clear. Here we use two T6SS-active antagonistic bacterial species, Aeromonas hydrophila and Vibrio cholerae, to demonstrate that interspecies protection is dependent on effectors. A. hydrophila and V. cholerae do not share conserved immunity genes but could coexist equally in a mixture. However, mutants lacking the T6SS or effectors were effectively eliminated by the competing wild-type strain. Time-lapse microscopic analyses showed that mutually lethal interactions drive the segregation of mixed species into distinct single-species clusters by eliminating interspersed single cells. Cluster formation provides herd protection by abolishing lethal interactions inside each cluster and restricting the interactions to the boundary. Using an agent-based modeling approach, we simulated the antagonistic interactions of two hypothetical species. The resulting simulations recapitulated our experimental observations. These results provide mechanistic insights regarding the general role of microbial weapons in determining the structures of complex multispecies communities. IMPORTANCE Investigating the warfare of microbes allows us to better understand the ecological relationships in complex microbial communities such as the human microbiota. Here we use the T6SS, a deadly bacterial weapon, as a model to demonstrate the importance of lethal interactions in determining community structures and the exchange of genetic materials. This simplified model elucidates a mechanism of microbial herd protection by which competing antagonistic species can coexist in the same niche, despite their diverse mutually destructive activities. Our results also suggest that antagonistic interactions impose strong selection that could promote multicellular organism-like social behaviors and contribute to the transition to multicellularity during evolution. PMID:27637882

  15. Photodynamic treatment of endodontic polymicrobial infection in vitro

    PubMed Central

    Fimple, Jacob Lee; Fontana, Carla Raquel; Foschi, Federico; Ruggiero, Karriann; Song, Xiaoqing; Pagonis, Tom C.; Tanner, Anne C. R.; Kent, Ralph; Doukas, Apostolos G.; Stashenko, Philip P.; Soukos, Nikolaos S.

    2008-01-01

    We investigated the photodynamic effects of methylene blue (MB) on multi-species root canal biofilms comprising Actinomyces israelii, Fusobacterium nucleatum subspecies nucleatum, Porphyromonas gingivalis and Prevotella intermedia in experimentally infected root canals of extracted human teeth in vitro. The four test microorganisms were detected in root canals using DNA probes. Scanning electron microscopy (SEM) showed the presence of biofilms in root canals prior to therapy. Root canal systems were incubated with MB (25 µg/ml) for 10 minutes followed by exposure to red light at 665 nm with an energy fluence of 30 J/cm2. Light was delivered from a diode laser via a 250 µm diameter polymethyl methacrylate optical fiber that uniformly distributed light at 360°. Photodynamic therapy (PDT) achieved up to 80% reduction of colony-forming unit counts. We conclude that PDT can be an effective adjunct to standard endodontic antimicrobial treatment when the PDT parameters are optimized. PMID:18498901

  16. Microbial Community Composition Impacts Pathogen Iron Availability during Polymicrobial Infection

    PubMed Central

    Stacy, Apollo; Whiteley, Marvin

    2016-01-01

    Iron is an essential nutrient for bacterial pathogenesis, but in the host, iron is tightly sequestered, limiting its availability for bacterial growth. Although this is an important arm of host immunity, most studies examine how bacteria respond to iron restriction in laboratory rather than host settings, where the microbiome can potentially alter pathogen strategies for acquiring iron. One of the most important transcriptional regulators controlling bacterial iron homeostasis is Fur. Here we used a combination of RNA-seq and chromatin immunoprecipitation (ChIP)-seq to characterize the iron-restricted and Fur regulons of the biofilm-forming opportunistic pathogen Aggregatibacter actinomycetemcomitans. We discovered that iron restriction and Fur regulate 4% and 3.5% of the genome, respectively. While most genes in these regulons were related to iron uptake and metabolism, we found that Fur also directly regulates the biofilm-dispersing enzyme Dispersin B, allowing A. actinomycetemcomitans to escape from iron-scarce environments. We then leveraged these datasets to assess the availability of iron to A. actinomycetemcomitans in its primary infection sites, abscesses and the oral cavity. We found that A. actinomycetemcomitans is not restricted for iron in a murine abscess mono-infection, but becomes restricted for iron upon co-infection with the oral commensal Streptococcus gordonii. Furthermore, in the transition from health to disease in human gum infection, A. actinomycetemcomitans also becomes restricted for iron. These results suggest that host iron availability is heterogeneous and dependent on the infecting bacterial community. PMID:27973608

  17. Sinomenine hydrochloride protects against polymicrobial sepsis via autophagy.

    PubMed

    Jiang, Yu; Gao, Min; Wang, Wenmei; Lang, Yuejiao; Tong, Zhongyi; Wang, Kangkai; Zhang, Huali; Chen, Guangwen; Liu, Meidong; Yao, Yongming; Xiao, Xianzhong

    2015-01-23

    Sepsis, a systemic inflammatory response to infection, is the major cause of death in intensive care units (ICUs). The mortality rate of sepsis remains high even though the treatment and understanding of sepsis both continue to improve. Sinomenine (SIN) is a natural alkaloid extracted from Chinese medicinal plant Sinomenium acutum, and its hydrochloride salt (Sinomenine hydrochloride, SIN-HCl) is widely used to treat rheumatoid arthritis (RA). However, its role in sepsis remains unclear. In the present study, we investigated the role of SIN-HCl in sepsis induced by cecal ligation and puncture (CLP) in BALB/c mice and the corresponding mechanism. SIN-HCl treatment improved the survival of BALB/c mice that were subjected to CLP and reduced multiple organ dysfunction and the release of systemic inflammatory mediators. Autophagy activities were examined using Western blotting. The results showed that CLP-induced autophagy was elevated, and SIN-HCl treatment further strengthened the autophagy activity. Autophagy blocker 3-methyladenine (3-MA) was used to investigate the mechanism of SIN-HCl in vitro. Autophagy activities were determined by examining the autophagosome formation, which was shown as microtubule-associated protein light chain 3 (LC3) puncta with green immunofluorescence. SIN-HCl reduced lipopolysaccharide (LPS)-induced inflammatory cytokine release and increased autophagy in peritoneal macrophages (PM). 3-MA significantly decreased autophagosome formation induced by LPS and SIN-HCl. The decrease of inflammatory cytokines caused by SIN-HCl was partially aggravated by 3-MA treatment. Taken together, our results indicated that SIN-HCl could improve survival, reduce organ damage, and attenuate the release of inflammatory cytokines induced by CLP, at least in part through regulating autophagy activities.

  18. Sinomenine Hydrochloride Protects against Polymicrobial Sepsis via Autophagy

    PubMed Central

    Jiang, Yu; Gao, Min; Wang, Wenmei; Lang, Yuejiao; Tong, Zhongyi; Wang, Kangkai; Zhang, Huali; Chen, Guangwen; Liu, Meidong; Yao, Yongming; Xiao, Xianzhong

    2015-01-01

    Sepsis, a systemic inflammatory response to infection, is the major cause of death in intensive care units (ICUs). The mortality rate of sepsis remains high even though the treatment and understanding of sepsis both continue to improve. Sinomenine (SIN) is a natural alkaloid extracted from Chinese medicinal plant Sinomenium acutum, and its hydrochloride salt (Sinomenine hydrochloride, SIN-HCl) is widely used to treat rheumatoid arthritis (RA). However, its role in sepsis remains unclear. In the present study, we investigated the role of SIN-HCl in sepsis induced by cecal ligation and puncture (CLP) in BALB/c mice and the corresponding mechanism. SIN-HCl treatment improved the survival of BALB/c mice that were subjected to CLP and reduced multiple organ dysfunction and the release of systemic inflammatory mediators. Autophagy activities were examined using Western blotting. The results showed that CLP-induced autophagy was elevated, and SIN-HCl treatment further strengthened the autophagy activity. Autophagy blocker 3-methyladenine (3-MA) was used to investigate the mechanism of SIN-HCl in vitro. Autophagy activities were determined by examining the autophagosome formation, which was shown as microtubule-associated protein light chain 3 (LC3) puncta with green immunofluorescence. SIN-HCl reduced lipopolysaccharide (LPS)-induced inflammatory cytokine release and increased autophagy in peritoneal macrophages (PM). 3-MA significantly decreased autophagosome formation induced by LPS and SIN-HCl. The decrease of inflammatory cytokines caused by SIN-HCl was partially aggravated by 3-MA treatment. Taken together, our results indicated that SIN-HCl could improve survival, reduce organ damage, and attenuate the release of inflammatory cytokines induced by CLP, at least in part through regulating autophagy activities. PMID:25625512

  19. Comparative Metagenomics of the Polymicrobial Black Band Disease of Corals.

    PubMed

    Meyer, Julie L; Paul, Valerie J; Raymundo, Laurie J; Teplitski, Max

    2017-01-01

    Black Band Disease (BBD), the destructive microbial consortium dominated by the cyanobacterium Roseofilum reptotaenium, affects corals worldwide. While the taxonomic composition of BBD consortia has been well-characterized, substantially less is known about its functional repertoire. We sequenced the metagenomes of Caribbean and Pacific black band mats and cultured Roseofilum and obtained five metagenome-assembled genomes (MAGs) of Roseofilum, nine of Proteobacteria, and 12 of Bacteroidetes. Genomic content analysis suggests that Roseofilum is a source of organic carbon and nitrogen, as well as natural products that may influence interactions between microbes. Proteobacteria and Bacteroidetes members of the disease consortium are suited to the degradation of amino acids, proteins, and carbohydrates. The accumulation of sulfide underneath the black band mat, in part due to a lack of sulfur oxidizers, contributes to the lethality of the disease. The presence of sulfide:quinone oxidoreductase genes in all five Roseofilum MAGs and in the MAGs of several heterotrophs demonstrates that resistance to sulfide is an important characteristic for members of the BBD consortium.

  20. Comparative Metagenomics of the Polymicrobial Black Band Disease of Corals

    PubMed Central

    Meyer, Julie L.; Paul, Valerie J.; Raymundo, Laurie J.; Teplitski, Max

    2017-01-01

    Black Band Disease (BBD), the destructive microbial consortium dominated by the cyanobacterium Roseofilum reptotaenium, affects corals worldwide. While the taxonomic composition of BBD consortia has been well-characterized, substantially less is known about its functional repertoire. We sequenced the metagenomes of Caribbean and Pacific black band mats and cultured Roseofilum and obtained five metagenome-assembled genomes (MAGs) of Roseofilum, nine of Proteobacteria, and 12 of Bacteroidetes. Genomic content analysis suggests that Roseofilum is a source of organic carbon and nitrogen, as well as natural products that may influence interactions between microbes. Proteobacteria and Bacteroidetes members of the disease consortium are suited to the degradation of amino acids, proteins, and carbohydrates. The accumulation of sulfide underneath the black band mat, in part due to a lack of sulfur oxidizers, contributes to the lethality of the disease. The presence of sulfide:quinone oxidoreductase genes in all five Roseofilum MAGs and in the MAGs of several heterotrophs demonstrates that resistance to sulfide is an important characteristic for members of the BBD consortium. PMID:28458657

  1. Protective effect of Aloe vera on polymicrobial sepsis in mice.

    PubMed

    Yun, Nari; Lee, Chan-Ho; Lee, Sun-Mee

    2009-06-01

    Sepsis is an acute life-threatening clinical condition and remains the major cause of death in intensive care units. The primary pathophysiologic event central to the septic response is an overwhelming activation of the inflammatory system and countervailing response from the anti-inflammatory system. However, the cause of this perturbation has yet to be elucidated. In this study, we report that Aloe vera therapeutically reverses the lethality induced by cecal ligation and puncture (CLP), a clinically relevant model of sepsis. The administration of Aloe vera ameliorated the multiple organ dysfunction syndrome, as evidenced by the serum levels of biochemical parameters and histological changes. In order to investigate the pharmacological mechanism of Aloe vera, the levels of the cytokines, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-6 were determined by ELISA at various time points. The increases in the levels of TNF-alpha, IL-1beta, and IL-6 were attenuated by Aloe vera.In vivo administration of Aloe vera also markedly enhanced bacterial clearance. Our findings suggest that Aloe vera could be a potential therapeutic agent for the clinical treatment of sepsis.

  2. Returning Samples from Enceladus

    NASA Astrophysics Data System (ADS)

    Tsou, P.; Kanik, I.; Brownlee, D.; McKay, C.; Anbar, A.; Glavin, D.; Yano, H.

    2012-12-01

    From the first half century of space exploration, we have obtained samples only from the Moon, comet Wild 2, the Solar Wind and the asteroid Itokawa. The in-depth analyses of these samples in terrestrial laboratories have yielded profound knowledge that could not have been obtained without the returned samples. While obtaining samples from Solar System bodies is crucial science, it is rarely done due to cost and complexity. Cassini's discovery of geysers on Enceladus and organic materials, indicate that there is an exceptional opportunity and science rational to do a low-cost flyby sample return mission, similar to what was done by the Stardust. The earliest low cost possible flight opportunity is the next Discovery Mission [Tsou et al 2012]. Enceladus Plume Discovery - While Voyager provided evidence for young surfaces on Enceladus, the existence of Enceladus plumes was discovered by Cassini. Enceladus and comets are the only known solar system bodies that have jets enabling sample collection without landing or surface contact. Cassini in situ Findings -Cassini's made many discoveries at Saturn, including the break up of large organics in the plumes of Enceladus. Four prime criteria for habitability are liquid water, a heat source, organics and nitrogen [McKay et al. 2008, Waite et al. 2009, Postberg et al. 2011]. Out of all the NASA designated habitability targets, Enceladus is the single body that presents evidence for all four criteria. Significant advancement in the exploration of the biological potential of Enceladus can be made on returned samples in terrestrial laboratories where the full power of state-of-the-art laboratory instrumentation and procedures can be used. Without serious limits on power, mass or even cost, terrestrial laboratories provide the ultimate in analytical capability, adaptability, reproducibility and reliability. What Questions can Samples Address? - Samples collected from the Enceladus plume will enable a thorough and replicated

  3. Lunar sample analysis

    NASA Technical Reports Server (NTRS)

    Housley, R. M.

    1978-01-01

    Flameless atomic abosrption, X-ray photoemission spectroscopy, ferromagnetic resonance, scanning electron microscopy, and Moessbauer spectroscopy were used to investigate the evolution of the lunar regolith, the transport of volatile trace metals, and the surface composition of lunar samples. The development of a model for lunar volcanic eruptions is also discussed.

  4. Randomization and sampling issues

    USGS Publications Warehouse

    Geissler, P.H.

    1996-01-01

    The need for randomly selected routes and other sampling issues have been debated by the Amphibian electronic discussion group. Many excellent comments have been made, pro and con, but we have not reached consensus yet. This paper brings those comments together and attempts a synthesis. I hope that the resulting discussion will bring us closer to a consensus.

  5. Sampling for Chemical Analysis.

    ERIC Educational Resources Information Center

    Kratochvil, Byron; And Others

    1984-01-01

    This review, designed to make analysts aware of uncertainties introduced into analytical measurements during sampling, is organized under these headings: general considerations; theory; standards; and applications related to mineralogy, soils, sediments, metallurgy, atmosphere, water, biology, agriculture and food, medical and clinical areas, oil…

  6. Driven Boson Sampling

    NASA Astrophysics Data System (ADS)

    Barkhofen, Sonja; Bartley, Tim J.; Sansoni, Linda; Kruse, Regina; Hamilton, Craig S.; Jex, Igor; Silberhorn, Christine

    2017-01-01

    Sampling the distribution of bosons that have undergone a random unitary evolution is strongly believed to be a computationally hard problem. Key to outperforming classical simulations of this task is to increase both the number of input photons and the size of the network. We propose driven boson sampling, in which photons are input within the network itself, as a means to approach this goal. We show that the mean number of photons entering a boson sampling experiment can exceed one photon per input mode, while maintaining the required complexity, potentially leading to less stringent requirements on the input states for such experiments. When using heralded single-photon sources based on parametric down-conversion, this approach offers an ˜e -fold enhancement in the input state generation rate over scattershot boson sampling, reaching the scaling limit for such sources. This approach also offers a dramatic increase in the signal-to-noise ratio with respect to higher-order photon generation from such probabilistic sources, which removes the need for photon number resolution during the heralding process as the size of the system increases.

  7. Sampling for Chemical Analysis.

    ERIC Educational Resources Information Center

    Kratochvil, Byron; And Others

    1984-01-01

    This review, designed to make analysts aware of uncertainties introduced into analytical measurements during sampling, is organized under these headings: general considerations; theory; standards; and applications related to mineralogy, soils, sediments, metallurgy, atmosphere, water, biology, agriculture and food, medical and clinical areas, oil…

  8. Proficiency Sample Project.

    ERIC Educational Resources Information Center

    Apodaca, Mary

    The instrument for Colorado's Foreign Language Proficiency Sample Project and directions for its administration are provided in this document. The project is a voluntary, teacher-designed and -administered effort to standardize high school student language proficiency assessment techniques. The materials are used in teacher workshops. The…

  9. Using Language Sample Databases

    ERIC Educational Resources Information Center

    Heilmann, John J.; Miller, Jon F.; Nockerts, Ann

    2010-01-01

    Purpose: Over the past 50 years, language sample analysis (LSA) has evolved from a powerful research tool that is used to document children's linguistic development into a powerful clinical tool that is used to identify and describe the language skills of children with language impairment. The Systematic Analysis of Language Transcripts (SALT; J.…

  10. Lunar sample analysis

    NASA Technical Reports Server (NTRS)

    Housley, R. M.

    1986-01-01

    A wide variety of lunar sample and meteorite studies were performed. Abstracts of the most recent reports are also attached. Experimental techniques employed have included scanning electron microscopy, transmission electron microscopy, Mossbauer spectroscopy, atomic absorption analysis and a variety of simulation studies.

  11. Beliefs Underlying Random Sampling.

    ERIC Educational Resources Information Center

    Pollatsek, Alexander; And Others

    The general question examined by this study was whether the tendency of subjects to ignore the known score in giving the best guess for a sample mean was due to a descriptive heuristic such as representativeness or to a mechanistic one such as active balancing. Two experiments were conducted. In Experiment 1, subjects estimated: (1) the mean of a…

  12. Groundwater sampling: Chapter 5

    USGS Publications Warehouse

    Wang, Qingren; Munoz-Carpena, Rafael; Foster, Adam; Migliaccio, Kati W.; Li, Yuncong; Migliaccio, Kati

    2011-01-01

    Discussing an array of water quality topics, from water quality regulations and criteria, to project planning and sampling activities, this book outlines a framework for improving water quality programs. Using this framework, you can easily put the proper training and tools in place for better management of water resources.

  13. Comparing Organizational Sampling Frames.

    ERIC Educational Resources Information Center

    Kalleberg, Arne L.; And Others

    1990-01-01

    Compares costs and effectiveness of five organizational sampling frames (direct enumeration, unemployment insurance (UI) forms, Dun and Bradstreet's Market Identifier (DMI) files, telephone directory white pages, and chamber of commerce membership directories) at identifying a population of business organizations in Durham County, North Carolina.…

  14. MELFI Sample Insertion

    NASA Image and Video Library

    2010-06-28

    ISS024-E-006699 (28 June 2010) --- NASA astronaut Doug Wheelock, Expedition 24 flight engineer, prepares to insert biological samples into trays in the Minus Eighty Laboratory Freezer for ISS-2 (MELFI-2) in the Destiny laboratory of the International Space Station.

  15. MELFI Sample Insertion

    NASA Image and Video Library

    2010-07-02

    ISS024-E-007346 (2 July 2010) --- NASA astronauts Tracy Caldwell Dyson (background) and Shannon Walker, both Expedition 24 flight engineers, prepare to insert biological samples in a dewar tray in the Minus Eighty Laboratory Freezer for ISS (MELFI-1) in the Kibo laboratory of the International Space Station.

  16. MELFI Sample Insertion

    NASA Image and Video Library

    2010-06-28

    ISS024-E-006697 (28 June 2010) --- NASA astronaut Doug Wheelock, Expedition 24 flight engineer, prepares to insert biological samples into trays in the Minus Eighty Laboratory Freezer for ISS-2 (MELFI-2) in the Destiny laboratory of the International Space Station.

  17. Drafting Work Sample.

    ERIC Educational Resources Information Center

    Shawsheen Valley Regional Vocational-Technical High School, Billerica, MA.

    This manual contains a work sample intended to assess a handicapped student's interest in and to screen interested students into a training program in basic mechanical drawing. (The course is based on the entry level of an assistant drafter.) Section 1 describes the assessment, correlates the work performed and worker traits required for…

  18. Color Discrimination Work Sample.

    ERIC Educational Resources Information Center

    Shawsheen Valley Regional Vocational-Technical High School, Billerica, MA.

    This manual contains a work sample intended to assess a handicapped student's ability to see likenesses or differences in colors or shades, identifying or matching certain colors, and selecting colors that go together. Section 1 describes the assessment and lists related occupations and DOT codes. Instructions to the evaluator are provided in the…

  19. Drill Press Work Sample.

    ERIC Educational Resources Information Center

    Shawsheen Valley Regional Vocational-Technical High School, Billerica, MA.

    This manual contains a work sample intended to assess a handicapped student's interest in and to screen interested students into a training program in basic machine shop I. (The course is based on the entry level of the drill press operator.) Section 1 describes the assessment, correlates the work performed and worker traits required for…

  20. Electrical Wiring Work Sample.

    ERIC Educational Resources Information Center

    Shawsheen Valley Regional Vocational-Technical High School, Billerica, MA.

    This manual contains a work sample intended to screen handicapped students' interest in and to screen interested students into a training program in basic electricity. (The course is based on the entry level of an electrician helper.) Section 1 describes the assessment, correlates the work performed and worker traits required for completing the…

  1. Stardust Sample Return

    NASA Image and Video Library

    2006-01-17

    This image shows the return capsule inside a protective covering. The capsule, which landed at 2:10 a.m. Pacific time 3:10 a.m. Mountain time, contains cometary and interstellar samples gathered by NASA Stardust spacecraft.

  2. ANNULAR IMPACTOR SAMPLING DEVICE

    DOEpatents

    Tait, G.W.C.

    1959-03-31

    A high-rate air sampler capable of sampling alphaemitting particles as small as 0.5 microns is described. The device is a cylindrical shaped cup that fits in front of a suction tube and which has sticky grease coating along its base. Suction forces contaminated air against the periodically monitored particle absorbing grease.

  3. Using Language Sample Databases

    ERIC Educational Resources Information Center

    Heilmann, John J.; Miller, Jon F.; Nockerts, Ann

    2010-01-01

    Purpose: Over the past 50 years, language sample analysis (LSA) has evolved from a powerful research tool that is used to document children's linguistic development into a powerful clinical tool that is used to identify and describe the language skills of children with language impairment. The Systematic Analysis of Language Transcripts (SALT; J.…

  4. Color Discrimination Work Sample.

    ERIC Educational Resources Information Center

    Shawsheen Valley Regional Vocational-Technical High School, Billerica, MA.

    This manual contains a work sample intended to assess a handicapped student's ability to see likenesses or differences in colors or shades, identifying or matching certain colors, and selecting colors that go together. Section 1 describes the assessment and lists related occupations and DOT codes. Instructions to the evaluator are provided in the…

  5. Transition Path Sampling Methods

    NASA Astrophysics Data System (ADS)

    Dellago, C.; Bolhuis, P. G.; Geissler, P. L.

    Transition path sampling, based on a statistical mechanics in trajectory space, is a set of computational methods for the simulation of rare events in complex systems. In this chapter we give an overview of these techniques and describe their statistical mechanical basis as well as their application.

  6. Adaptive Sampling Designs.

    ERIC Educational Resources Information Center

    Flournoy, Nancy

    Designs for sequential sampling procedures that adapt to cumulative information are discussed. A familiar illustration is the play-the-winner rule in which there are two treatments; after a random start, the same treatment is continued as long as each successive subject registers a success. When a failure occurs, the other treatment is used until…

  7. Minimum variance geographic sampling

    NASA Technical Reports Server (NTRS)

    Terrell, G. R. (Principal Investigator)

    1980-01-01

    Resource inventories require samples with geographical scatter, sometimes not as widely spaced as would be hoped. A simple model of correlation over distances is used to create a minimum variance unbiased estimate population means. The fitting procedure is illustrated from data used to estimate Missouri corn acreage.

  8. Biological Sampling Variability Study

    SciTech Connect

    Amidan, Brett G.; Hutchison, Janine R.

    2016-11-08

    There are many sources of variability that exist in the sample collection and analysis process. This paper addresses many, but not all, sources of variability. The main focus of this paper was to better understand and estimate variability due to differences between samplers. Variability between days was also studied, as well as random variability within each sampler. Experiments were performed using multiple surface materials (ceramic and stainless steel), multiple contaminant concentrations (10 spores and 100 spores), and with and without the presence of interfering material. All testing was done with sponge sticks using 10-inch by 10-inch coupons. Bacillus atrophaeus was used as the BA surrogate. Spores were deposited using wet deposition. Grime was coated on the coupons which were planned to include the interfering material (Section 3.3). Samples were prepared and analyzed at PNNL using CDC protocol (Section 3.4) and then cultured and counted. Five samplers were trained so that samples were taken using the same protocol. Each sampler randomly sampled eight coupons each day, four coupons with 10 spores deposited and four coupons with 100 spores deposited. Each day consisted of one material being tested. The clean samples (no interfering materials) were run first, followed by the dirty samples (coated with interfering material). There was a significant difference in recovery efficiency between the coupons with 10 spores deposited (mean of 48.9%) and those with 100 spores deposited (mean of 59.8%). There was no general significant difference between the clean and dirty (containing interfering material) coupons or between the two surface materials; however, there was a significant interaction between concentration amount and presence of interfering material. The recovery efficiency was close to the same for coupons with 10 spores deposited, but for the coupons with 100 spores deposited, the recovery efficiency for the dirty samples was significantly larger (65

  9. Phoenix Test Sample Site

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image, acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on Sol 7, the seventh day of the mission (June 1, 2008), shows the so-called 'Knave of Hearts' first-dig test area to the north of the lander. The Robotic Arm's scraping blade left a small horizontal depression above where the sample was taken.

    Scientists speculate that white material in the depression left by the dig could represent ice or salts that precipitated into the soil. This material is likely the same white material observed in the sample in the Robotic Arm's scoop.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  10. Sample Analysis at Mars

    NASA Technical Reports Server (NTRS)

    Brinckerhoff, W. B.; Mahaffy, P. R.; Cabane, M.; Atreya, S. K.; Coll, P.; Cornish, T. J.; Harpold, D. N.; Israel, G.; Niemann, H. B.; Owen, T.

    2003-01-01

    The next landed missions to Mars, such as the planned Mars Science Laboratory and ExoMars, will require sample analysis capabilities refined well beyond what has been flown to date. A key science objective driving this requirement is the determination of the carbon inventory of Mars, and particularly the detection of organic compounds. While the gas chromatograph mass spectrometers (GC/MS) on the Viking landers did not detect any indigenous organics in near surface fines, it is possible that these measurements were not representative of Mars on the whole. That is, those compounds to which the GC/MS was sensitive would likely not have survived the strong oxidative decomposition in the regolith at the landing sites in question. The near surface fines could very well contain a significant quantity of refractory compounds that would not have been volatilized in the sample ovens on Viking. It is also possible that volatile organics exist on Mars in sedimentary, subsurface, or polar niches.

  11. Nonadiabatic transition path sampling

    NASA Astrophysics Data System (ADS)

    Sherman, M. C.; Corcelli, S. A.

    2016-07-01

    Fewest-switches surface hopping (FSSH) is combined with transition path sampling (TPS) to produce a new method called nonadiabatic path sampling (NAPS). The NAPS method is validated on a model electron transfer system coupled to a Langevin bath. Numerically exact rate constants are computed using the reactive flux (RF) method over a broad range of solvent frictions that span from the energy diffusion (low friction) regime to the spatial diffusion (high friction) regime. The NAPS method is shown to quantitatively reproduce the RF benchmark rate constants over the full range of solvent friction. Integrating FSSH within the TPS framework expands the applicability of both approaches and creates a new method that will be helpful in determining detailed mechanisms for nonadiabatic reactions in the condensed-phase.

  12. Phoenix Test Sample Site

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image, acquired by NASA's Phoenix Mars Lander's Surface Stereo Imager on Sol 7, the seventh day of the mission (June 1, 2008), shows the so-called 'Knave of Hearts' first-dig test area to the north of the lander. The Robotic Arm's scraping blade left a small horizontal depression above where the sample was taken.

    Scientists speculate that white material in the depression left by the dig could represent ice or salts that precipitated into the soil. This material is likely the same white material observed in the sample in the Robotic Arm's scoop.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  13. Lunar sample analysis

    NASA Technical Reports Server (NTRS)

    Tittmann, B. R.

    1975-01-01

    Previous studies have shown that very small amounts of absorbed volatiles only removed by outgassing in high vacuum and elevated temperatures-drastically increase the internal friction in terrestrial analogs of lunar basalt. Recently room temperature Q values as high as 2000 were achieved by thorough outgassing procedures in 10 to the 8th power torr. Results are presented on Q measurements for lunar rock 70215.85, along with some data on the effect on Q of a variety of gases. Data show that substantially greater increases in Q are obtainable in a lunar rock sample than in the terrestrial analog samples studied, and that in addition to H2O other gases also can make non-negligible contributions to the internal friction.

  14. Sampling system and method

    DOEpatents

    Decker, David L.; Lyles, Brad F.; Purcell, Richard G.; Hershey, Ronald Lee

    2017-03-07

    In one embodiment, the present disclosure provides an apparatus and method for supporting a tubing bundle during installation or removal. The apparatus includes a clamp for securing the tubing bundle to an external wireline. In various examples, the clamp is external to the tubing bundle or integral with the tubing bundle. According to one method, a tubing bundle and wireline are deployed together and the tubing bundle periodically secured to the wireline using a clamp. In another embodiment, the present disclosure provides an apparatus and method for coupling conduit segments together. A first pump obtains a sample and transmits it through a first conduit to a reservoir accessible by a second pump. The second pump further conducts the sample from the reservoir through a second conduit. In a specific example, one or more clamps are used to connect the first and/or second conduits to an external wireline.

  15. Apollo 11 lunar sample

    NASA Image and Video Library

    2009-06-24

    ISS020-E-14200 (FOR RELEASE 21 JULY 2009) --- A moon rock brought to Earth by Apollo 11, humans? first landing on the moon in July 1969, is shown as it floats aboard the International Space Station. Part of Earth can be seen through the window. The 3.6 billion year-old lunar sample was flown to the station aboard Space Shuttle mission STS-119 in April 2009 in honor of the July 2009 40th anniversary of the historic first moon landing. The rock, lunar sample 10072, was flown to the station to serve as a symbol of the nation?s resolve to continue the exploration of space. It will be returned on shuttle mission STS-128 to be publicly displayed.

  16. Apollo 11 lunar sample

    NASA Image and Video Library

    2009-06-24

    ISS020-E-014193 (FOR RELEASE 21 JULY 2009) --- A moon rock brought to Earth by Apollo 11, humans? first landing on the moon in July 1969, is shown as it floats aboard the International Space Station. Part of Earth can be seen through the window. The 3.6 billion year-old lunar sample was flown to the station aboard Space Shuttle mission STS-119 in April 2009 in honor of the July 2009 40th anniversary of the historic first moon landing. The rock, lunar sample 10072, was flown to the station to serve as a symbol of the nation?s resolve to continue the exploration of space. It will be returned on shuttle mission STS-128 to be publicly displayed.

  17. Apollo 11 lunar sample

    NASA Image and Video Library

    2009-06-24

    ISS020-E-14196 (FOR RELEASE 21 JULY 2009) --- A moon rock brought to Earth by Apollo 11, humans? first landing on the moon in July 1969, is shown as it floats aboard the International Space Station. Part of Earth can be seen through the window. The 3.6 billion year-old lunar sample was flown to the station aboard Space Shuttle mission STS-119 in April 2009 in honor of the July 2009 40th anniversary of the historic first moon landing. The rock, lunar sample 10072, was flown to the station to serve as a symbol of the nation?s resolve to continue the exploration of space. It will be returned on shuttle mission STS-128 to be publicly displayed.

  18. Cerenkov fiber sampling calorimeters

    SciTech Connect

    Arrington, K.; Kefford, D.; Kennedy, J.; Pisani, R.; Sanzeni, C.; Segall, K.; Wall, D.; Winn, D.R. ); Carey, R.; Dye, S.; Miller, J.; Sulak, L.; Worstell, W. ); Efremenko, Y.; Kamyshkov, Y.; Savin, A.; Shmakov, K.; Tarkovsky, E. )

    1994-08-01

    Clear optical fibers were used as a Cerenkov sampling media in Pb (electromagnetic) and Cu (hadron) absorbers in spaghetti calorimeters, for high rate and high radiation dose experiments, such as the forward region of high energy colliders. The fiber axes were aligned close to the direction of the incident particles (1[degree]--7[degree]). The 7 [lambda] deep hadron tower contained 2.8% by volume 1.5 mm diameter core clear plastic fibers. The 27 radiation length deep electromagnetic towers had packing fractions of 6.8% and 7.2% of 1 mm diameter core quartz fibers as the active Cerenkov sampling medium. The energy resolution on electrons and pions, energy response, pulse shapes and angular studies are presented.

  19. Seabed observation & sampling system

    USGS Publications Warehouse

    Blackwood, D.; Parolski, K.

    2001-01-01

    SEABOSS has proved to be a valuable addition to the USGS data-acquisition and processing field program. It has allowed researchers to collect high-quality images and seabed samples in a timely manner. It is a simple, dependable and trouble-free system with a track record of over 3,000 deployments. When used as part of the USGS seafloor mapping acquisition, processing, and ground-truth program, SEABOSS has been invaluable in providing information quickly and efficiently, with a minimum of downtime. SEABOSS enables scientists to collect high-quality images and samples of the seabed, essential to the study of sedimentary environments and biological habitats and to the interpretation of side-scan sonar and multibeam imagery, the most common tools for mapping the seabed.

  20. Natural sampling strategy

    NASA Technical Reports Server (NTRS)

    Hallum, C. R.; Basu, J. P. (Principal Investigator)

    1979-01-01

    A natural stratum-based sampling scheme and the aggregation procedures for estimating wheat area, yield, and production and their associated prediction error estimates are described. The methodology utilizes LANDSAT imagery and agrophysical data to permit an improved stratification in foreign areas by ignoring political boundaries and restratifying along boundaries that are more homogeneous with respect to the distribution of agricultural density, soil characteristics, and average climatic conditions. A summary of test results is given including a discussion of the various problems encountered.

  1. Digital Microfluidics Sample Analyzer

    NASA Technical Reports Server (NTRS)

    Pollack, Michael G.; Srinivasan, Vijay; Eckhardt, Allen; Paik, Philip Y.; Sudarsan, Arjun; Shenderov, Alex; Hua, Zhishan; Pamula, Vamsee K.

    2010-01-01

    Three innovations address the needs of the medical world with regard to microfluidic manipulation and testing of physiological samples in ways that can benefit point-of-care needs for patients such as premature infants, for which drawing of blood for continuous tests can be life-threatening in their own right, and for expedited results. A chip with sample injection elements, reservoirs (and waste), droplet formation structures, fluidic pathways, mixing areas, and optical detection sites, was fabricated to test the various components of the microfluidic platform, both individually and in integrated fashion. The droplet control system permits a user to control droplet microactuator system functions, such as droplet operations and detector operations. Also, the programming system allows a user to develop software routines for controlling droplet microactuator system functions, such as droplet operations and detector operations. A chip is incorporated into the system with a controller, a detector, input and output devices, and software. A novel filler fluid formulation is used for the transport of droplets with high protein concentrations. Novel assemblies for detection of photons from an on-chip droplet are present, as well as novel systems for conducting various assays, such as immunoassays and PCR (polymerase chain reaction). The lab-on-a-chip (a.k.a., lab-on-a-printed-circuit board) processes physiological samples and comprises a system for automated, multi-analyte measurements using sub-microliter samples of human serum. The invention also relates to a diagnostic chip and system including the chip that performs many of the routine operations of a central labbased chemistry analyzer, integrating, for example, colorimetric assays (e.g., for proteins), chemiluminescence/fluorescence assays (e.g., for enzymes, electrolytes, and gases), and/or conductometric assays (e.g., for hematocrit on plasma and whole blood) on a single chip platform.

  2. Water sample filtration unit

    USGS Publications Warehouse

    Skougstad, M.W.; Scarbro, G.F.

    1968-01-01

    A readily portable, all plastic, pressure filtration unit is described which greatly facilitates rapid micropore membrane field filtration of up to several liters of water with a minimum risk of inorganic chemical alteration or contamination of the sample. The unit accommodates standard 10.2-cm. (4-inch) diameter filters. The storage and carrying case serves as a convenient filter stand for both field and laboratory use.

  3. Nutrition: blood sample collection

    NASA Image and Video Library

    2007-03-20

    ISS014-E-17550 (20 March 2007) --- Astronaut Michael E. Lopez-Alegria, Expedition 14 commander and NASA space station science officer, prepares to insert a test sample in the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods.

  4. Nutrition: blood sample collection

    NASA Image and Video Library

    2007-03-20

    ISS014-E-17547 (20 March 2007) --- Astronaut Michael E. Lopez-Alegria, Expedition 14 commander and NASA space station science officer, prepares to insert a test sample in the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods.

  5. Natural sampling strategy

    NASA Technical Reports Server (NTRS)

    Hallum, C. R.; Basu, J. P. (Principal Investigator)

    1979-01-01

    A natural stratum-based sampling scheme and the aggregation procedures for estimating wheat area, yield, and production and their associated prediction error estimates are described. The methodology utilizes LANDSAT imagery and agrophysical data to permit an improved stratification in foreign areas by ignoring political boundaries and restratifying along boundaries that are more homogeneous with respect to the distribution of agricultural density, soil characteristics, and average climatic conditions. A summary of test results is given including a discussion of the various problems encountered.

  6. Advanced hierarchical distance sampling

    USGS Publications Warehouse

    Royle, Andy

    2016-01-01

    In this chapter, we cover a number of important extensions of the basic hierarchical distance-sampling (HDS) framework from Chapter 8. First, we discuss the inclusion of “individual covariates,” such as group size, in the HDS model. This is important in many surveys where animals form natural groups that are the primary observation unit, with the size of the group expected to have some influence on detectability. We also discuss HDS integrated with time-removal and double-observer or capture-recapture sampling. These “combined protocols” can be formulated as HDS models with individual covariates, and thus they have a commonality with HDS models involving group structure (group size being just another individual covariate). We cover several varieties of open-population HDS models that accommodate population dynamics. On one end of the spectrum, we cover models that allow replicate distance sampling surveys within a year, which estimate abundance relative to availability and temporary emigration through time. We consider a robust design version of that model. We then consider models with explicit dynamics based on the Dail and Madsen (2011) model and the work of Sollmann et al. (2015). The final major theme of this chapter is relatively newly developed spatial distance sampling models that accommodate explicit models describing the spatial distribution of individuals known as Point Process models. We provide novel formulations of spatial DS and HDS models in this chapter, including implementations of those models in the unmarked package using a hack of the pcount function for N-mixture models.

  7. Sustainable Mars Sample Return

    NASA Technical Reports Server (NTRS)

    Alston, Christie; Hancock, Sean; Laub, Joshua; Perry, Christopher; Ash, Robert

    2011-01-01

    The proposed Mars sample return mission will be completed using natural Martian resources for the majority of its operations. The system uses the following technologies: In-Situ Propellant Production (ISPP), a methane-oxygen propelled Mars Ascent Vehicle (MAV), a carbon dioxide powered hopper, and a hydrogen fueled balloon system (large balloons and small weather balloons). The ISPP system will produce the hydrogen, methane, and oxygen using a Sabatier reactor. a water electrolysis cell, water extracted from the Martian surface, and carbon dioxide extracted from the Martian atmosphere. Indigenous hydrogen will fuel the balloon systems and locally-derived methane and oxygen will fuel the MAV for the return of a 50 kg sample to Earth. The ISPP system will have a production cycle of 800 days and the estimated overall mission length is 1355 days from Earth departure to return to low Earth orbit. Combining these advanced technologies will enable the proposed sample return mission to be executed with reduced initial launch mass and thus be more cost efficient. The successful completion of this mission will serve as the next step in the advancement of Mars exploration technology.

  8. Same-day diagnostic and surveillance data for tuberculosis via whole genome sequencing of direct respiratory samples.

    PubMed

    Votintseva, Antonina A; Bradley, Phelim; Pankhurst, Louise; Del Ojo Elias, Carlos; Loose, Matthew; Nilgiriwala, Kayzad; Chatterjee, Anirvan; Smith, E Grace; Sanderson, Nicolas; Walker, Timothy M; Morgan, Marcus R; Wyllie, David H; Walker, A Sarah; Peto, Tim E A; Crook, Derrick W; Iqbal, Zamin

    2017-03-08

    Routine full characterization of Mycobacterium tuberculosis (TB) is culture-based, taking many weeks. Whole-genome sequencing (WGS) can generate antibiotic susceptibility profiles to inform treatment, augmented with strain information for global surveillance; such data could be transformative if provided at or near point of care.We demonstrate a low-cost DNA extraction method for TB WGS direct from patient samples. We initially evaluated the method using the Illumina MiSeq sequencer (40 smear-positive respiratory samples, obtained after routine clinical testing, and 27 matched liquid cultures). M. tuberculosis was identified in all 39 samples from which DNA was successfully extracted. Sufficient data for antibiotic susceptibility prediction was obtained from 24 (62%) samples; all results were concordant with reference laboratory phenotypes. Phylogenetic placement was concordant between direct and cultured samples. Using an Illumina MiSeq/MiniSeq the workflow from patient sample to results can be completed in 44/16 hours at a reagent cost of £96/£198 per sample.We then employed a non-specific PCR-based library preparation method for sequencing on an Oxford Nanopore Technologies MinION sequencer. We applied this to cultured Mycobacterium bovis BCG strain (BCG), and to combined culture-negative sputum DNA and BCG DNA. For flowcell version R9.4, the estimated turnaround time from patient to identification of BCG, detection of pyrazinamide resistance, and phylogenetic placement was 7.5 hours, with full susceptibility results 5 hours later. Antibiotic susceptibility predictions were fully concordant. A critical advantage of the MinION is the ability to continue sequencing until sufficient coverage is obtained, providing a potential solution to the problem of variable amounts of M. tuberculosis in direct samples.

  9. 340 Representative sampling verification tank sampling and analysis plan

    SciTech Connect

    Olander, A.R., Westinghouse Hanford

    1996-08-21

    This Sampling and Analysis Plan contains requirements for characterizing the 340 vault tank 1. The objective of the sampling and characterization is to determine if the tank is homogeneous when agitated and which sampling method provides the most representative sample. A secondary objective is to collect and characterize solid samples.

  10. NID Copper Sample Analysis

    SciTech Connect

    Kouzes, Richard T.; Zhu, Zihua

    2011-09-12

    The current focal point of the nuclear physics program at PNNL is the MAJORANA DEMONSTRATOR, and the follow-on Tonne-Scale experiment, a large array of ultra-low background high-purity germanium detectors, enriched in 76Ge, designed to search for zero-neutrino double-beta decay (0νββ). This experiment requires the use of germanium isotopically enriched in 76Ge. The MAJORANA DEMONSTRATOR is a DOE and NSF funded project with a major science impact. The DEMONSTRATOR will utilize 76Ge from Russia, but for the Tonne-Scale experiment it is hoped that an alternate technology, possibly one under development at Nonlinear Ion Dynamics (NID), will be a viable, US-based, lower-cost source of separated material. Samples of separated material from NID require analysis to determine the isotopic distribution and impurities. DOE is funding NID through an SBIR grant for development of their separation technology for application to the Tonne-Scale experiment. The Environmental Molecular Sciences facility (EMSL), a DOE user facility at PNNL, has the required mass spectroscopy instruments for making isotopic measurements that are essential to the quality assurance for the MAJORANA DEMONSTRATOR and for the development of the future separation technology required for the Tonne-Scale experiment. A sample of isotopically separated copper was provided by NID to PNNL in January 2011 for isotopic analysis as a test of the NID technology. The results of that analysis are reported here. A second sample of isotopically separated copper was provided by NID to PNNL in August 2011 for isotopic analysis as a test of the NID technology. The results of that analysis are also reported here.

  11. Air Sampling Filter

    NASA Technical Reports Server (NTRS)

    1980-01-01

    General Metal Works' Accu-Vol is a high-volume air sampling system used by many government agencies to monitor air quality for pollution control purposes. Procedure prevents possible test-invalidating contamination from materials other than particulate pollutants, caused by manual handling or penetration of windblown matter during transit, a cassette was developed in which the filter is sealed within a metal frame and protected in transit by a snap-on aluminum cover, thus handled only under clean conditions in the laboratory.

  12. Stack sampling apparatus

    DOEpatents

    Lind, Randall F; Lloyd, Peter D; Love, Lonnie J; Noakes, Mark W; Pin, Francois G; Richardson, Bradley S; Rowe, John C

    2014-09-16

    An apparatus for obtaining samples from a structure includes a support member, at least one stabilizing member, and at least one moveable member. The stabilizing member has a first portion coupled to the support member and a second portion configured to engage with the structure to restrict relative movement between the support member and the structure. The stabilizing member is radially expandable from a first configuration where the second portion does not engage with a surface of the structure to a second configuration where the second portion engages with the surface of the structure.

  13. Germanium-76 Sample Analysis

    SciTech Connect

    Kouzes, Richard T.; Engelhard, Mark H.; Zhu, Zihua

    2011-04-01

    The MAJORANA DEMONSTRATOR is a large array of ultra-low background high-purity germanium detectors, enriched in 76Ge, designed to search for zero-neutrino double-beta decay (0νββ). The DEMONSTRATOR will utilize 76Ge from Russia, and the first one gram sample was received from the supplier for analysis on April 24, 2011. The Environmental Molecular Sciences facility, a DOE user facility at PNNL, was used to make the required isotopic and chemical purity measurements that are essential to the quality assurance for the MAJORANA DEMONSTRATOR. The results of this first analysis are reported here.

  14. Pulsed field sample neutralization

    DOEpatents

    Appelhans, Anthony D.; Dahl, David A.; Delmore, James E.

    1990-01-01

    An apparatus and method for alternating voltage and for varying the rate of extraction during the extraction of secondary particles, resulting in periods when either positive ions, or negative ions and electrons are extracted at varying rates. Using voltage with alternating charge during successive periods to extract particles from materials which accumulate charge opposite that being extracted causes accumulation of surface charge of opposite sign. Charge accumulation can then be adjusted to a ratio which maintains a balance of positive and negative charge emission, thus maintaining the charge neutrality of the sample.

  15. Phobos Sample Return mission

    NASA Astrophysics Data System (ADS)

    Zelenyi, Lev; Zakharov, A.; Martynov, M.; Polischuk, G.

    Very mysterious objects of the Solar system are the Martian satellites, Phobos and Deimos. Attempt to study Phobos in situ from an orbiter and from landers have been done by the Russian mission FOBOS in 1988. However, due to a malfunction of the onboard control system the landers have not been delivered to the Phobos surface. A new robotics mission to Phobos is under development now in Russia. Its main goal is the delivery of samples of the Phobos surface material to the Earth for laboratory studies of its chemical, isotopic, mineral composition, age etc. Other goals are in situ studies of Phobos (regolith, internal structure, peculiarities in orbital and proper rotation), studies of Martian environment (dust, plasma, fields). The payload includes a number of scientific instruments: gamma and neutron spectrometers, gaschromatograph, mass spectrometers, IR spectrometer, seismometer, panoramic camera, dust sensor, plasma package. To implement the tasks of this mission a cruise-transfer spacecraft after the launch and the Earth-Mars interplanetary flight will be inserted into the first elliptical orbit around Mars, then after several corrections the spacecraft orbit will be formed very close to the Phobos orbit to keep the synchronous orbiting with Phobos. Then the spacecraft will encounter with Phobos and will land at the surface. After the landing the sampling device of the spacecraft will collect several samples of the Phobos regolith and will load these samples into the return capsule mounted at the returned vehicle. This returned vehicle will be launched from the mother spacecraft and after the Mars-Earth interplanetary flight after 11 monthes with reach the terrestrial atmosphere. Before entering into the atmosphere the returned capsule will be separated from the returned vehicle and will hopefully land at the Earth surface. The mother spacecraft at the Phobos surface carrying onboard scientific instruments will implement the "in situ" experiments during an year

  16. Inspecting Engineering Samples

    NASA Image and Video Library

    2017-09-27

    Goddard's Ritsko Wins 2011 SAVE Award The winner of the 2011 SAVE Award is Matthew Ritsko, a Goddard financial manager. His tool lending library would track and enable sharing of expensive space-flight tools and hardware after projects no longer need them. This set of images represents the types of tools used at NASA. To read more go to: www.nasa.gov/topics/people/features/ritsko-save.html Dr. Doug Rabin (Code 671) and PI La Vida Cooper (Code 564) inspect engineering samples of the HAS-2 imager which will be tested and readout using a custom ASIC with a 16-bit ADC (analog to digital converter) and CDS (correlated double sampling) circuit designed by the Code 564 ASIC group as a part of an FY10 IRAD. The purpose of the IRAD was to develop and high resolution digitizer for Heliophysics applications such as imaging. Future goals for the collaboration include characterization testing and eventually a sounding rocket flight of the integrated system. *ASIC= Application Specific Integrated Circuit NASA/GSFC/Chris Gunn

  17. NID Copper Sample Analysis

    SciTech Connect

    Kouzes, Richard T.; Zhu, Zihua

    2011-02-01

    The current focal point of the nuclear physics program at PNNL is the MAJORANA DEMONSTRATOR, and the follow-on Tonne-Scale experiment, a large array of ultra-low background high-purity germanium detectors, enriched in 76Ge, designed to search for zero-neutrino double-beta decay (0νββ). This experiment requires the use of germanium isotopically enriched in 76Ge. The DEMONSTRATOR will utilize 76Ge from Russia, but for the Tonne-Scale experiment it is hoped that an alternate technology under development at Nonlinear Ion Dynamics (NID) will be a viable, US-based, lower-cost source of separated material. Samples of separated material from NID require analysis to determine the isotopic distribution and impurities. The MAJORANA DEMONSTRATOR is a DOE and NSF funded project with a major science impact. DOE is funding NID through an SBIR grant for development of their separation technology for application to the Tonne-Scale experiment. The Environmental Molecular Sciences facility (EMSL), a DOE user facility at PNNL, has the required mass spectroscopy instruments for making these isotopic measurements that are essential to the quality assurance for the MAJORANA DEMONSTRATOR and for the development of the future separation technology required for the Tonne-Scale experiment. A sample of isotopically separated copper was provided by NID to PNNL for isotopic analysis as a test of the NID technology. The results of that analysis are reported here.

  18. Fluid sampling tool

    DOEpatents

    Garcia, A.R.; Johnston, R.G.; Martinez, R.K.

    1999-05-25

    A fluid sampling tool is described for sampling fluid from a container. The tool has a fluid collecting portion which is drilled into the container wall, thereby affixing it to the wall. The tool may have a fluid extracting section which withdraws fluid collected by the fluid collecting section. The fluid collecting section has a fluted shank with an end configured to drill a hole into a container wall. The shank has a threaded portion for tapping the borehole. The shank is threadably engaged to a cylindrical housing having an inner axial passageway sealed at one end by a septum. A flexible member having a cylindrical portion and a bulbous portion is provided. The housing can be slid into an inner axial passageway in the cylindrical portion and sealed to the flexible member. The bulbous portion has an outer lip defining an opening. The housing is clamped into the chuck of a drill, the lip of the bulbous section is pressed against a container wall until the shank touches the wall, and the user operates the drill. Wall shavings (kerf) are confined in a chamber formed in the bulbous section as it folds when the shank advances inside the container. After sufficient advancement of the shank, an o-ring makes a seal with the container wall. 6 figs.

  19. Acclerated rare event sampling

    NASA Astrophysics Data System (ADS)

    Yevick, David

    2015-03-01

    We suggest a strategy for biased transition matrix Monte-Carlo calculations that both ensures the most rapid coverage of the entire computational window in the macroscopic variables of interest E --> and yields estimates of transition probabilities between states that are equally accurate in low and high probability regions. Further, paths between different low probability regions are sampled at regular intervals. For the case of a single E variable, a random system realization for which the value of E falls in e.g. the i:th histogram bin is generated. This state is perturbed and the resulting realization is rejected until a transition is observed to a neighboring bin, taken here as i + 1 . All accepted and rejected transitions are simultaneously employed to generate the elements of a transition matrix. Subsequently, only a transition to bin i + 2 is accepted and this procedure is continued until the last of the N bins comprising the computational window is sampled. The procedure is then repeated but in the direction of decreasing bin number. The probability distribution of E can then be obtained by e.g. repeatedly multiplying a random vector by the transition matrix.

  20. Fluid sampling tool

    DOEpatents

    Garcia, Anthony R.; Johnston, Roger G.; Martinez, Ronald K.

    1999-05-25

    A fluid sampling tool for sampling fluid from a container. The tool has a fluid collecting portion which is drilled into the container wall, thereby affixing it to the wall. The tool may have a fluid extracting section which withdraws fluid collected by the fluid collecting section. The fluid collecting section has a fluted shank with an end configured to drill a hole into a container wall. The shank has a threaded portion for tapping the borehole. The shank is threadably engaged to a cylindrical housing having an inner axial passageway sealed at one end by a septum. A flexible member having a cylindrical portion and a bulbous portion is provided. The housing can be slid into an inner axial passageway in the cylindrical portion and sealed to the flexible member. The bulbous portion has an outer lip defining an opening. The housing is clamped into the chuck of a drill, the lip of the bulbous section is pressed against a container wall until the shank touches the wall, and the user operates the drill. Wall shavings (kerf) are confined in a chamber formed in the bulbous section as it folds when the shank advances inside the container. After sufficient advancement of the shank, an o-ring makes a seal with the container wall.

  1. Conformational sampling techniques.

    PubMed

    Hatfield, Marcus P D; Lovas, Sándor

    2014-01-01

    The potential energy hyper-surface of a protein relates the potential energy of the protein to its conformational space. This surface is useful in determining the native conformation of a protein or in examining a statistical-mechanical ensemble of structures (canonical ensemble). In determining the potential energy hyper-surface of a protein three aspects must be considered; reducing the degrees of freedom, a method to determine the energy of each conformation and a method to sample the conformational space. For reducing the degrees of freedom the choice of solvent, coarse graining, constraining degrees of freedom and periodic boundary conditions are discussed. The use of quantum mechanics versus molecular mechanics and the choice of force fields are also discussed, as well as the sampling of the conformational space through deterministic and heuristic approaches. Deterministic methods include knowledge-based statistical methods, rotamer libraries, homology modeling, the build-up method, self-consistent electrostatic field, deformation methods, tree-based elimination and eigenvector following routines. The heuristic methods include Monte Carlo chain growing, energy minimizations, metropolis monte carlo and molecular dynamics. In addition, various methods to enhance the conformational search including the deformation or smoothing of the surface, scaling of system parameters, and multi copy searching are also discussed.

  2. Diagnosis of neonatal group B Streptococcus sepsis by nested-PCR of residual urine samples

    PubMed Central

    Cezarino, Bruno Nicolino; Yamamoto, Lidia; Del Negro, Gilda Maria Barbaro; Rocha, Daisy; Okay, Thelma Suely

    2008-01-01

    Group B streptococcus (GBS) remains the most common cause of early-onset sepsis in newborns. Laboratory gold-standard, broth culture methods are highly specific, but lack sensitivity. The aim of this study was to validate a nested-PCR and to determine whether residue volumes of urine samples obtained by non invasive, non sterile methods could be used to confirm neonatal GBS sepsis. The nested-PCR was performed with primers of the major GBS surface antigen. Unavailability of biological samples to perform life supporting exams, as well as others to elucidate the etiology of infections is a frequent problem concerning newborn patients. Nevertheless, we decided to include cases according to strict criteria: newborns had to present with signs and symptoms compatible with GBS infection; at least one of the following biological samples had to be sent for culture: blood, urine, or cerebrospinal fluid; availability of residue volumes of the samples sent for cultures, or of others collected on the day of hospitalization, prior to antibiotic therapy prescription, to be analyzed by PCR; favorable outcome after GBS empiric treatment. In only one newborn GBS infection was confirmed by cultures, while infection was only presumptive in the other three patients (they fulfilled inclusion criteria but were GBS-culture negative). From a total of 12 biological samples (5 blood, 3 CSF and 4 urine specimen), eight were tested by culture methods (2/8 were positive), and 8 were tested by PCR (7/8 were positive), and only 4 samples were simultaneously tested by both methods (1 positive by culture and 3 by PCR). In conclusion, although based on a restricted number of neonates and samples, our results suggest that the proposed nested-PCR might be used to diagnose GBS sepsis as it has successfully amplified the three types of biological samples analyzed (blood, urine and cerebrospinal fluid), and was more sensitive than culture methods as PCR in urine confirmed diagnosis in all four patients

  3. 46. VIEW OF SAMPLING ROOM FROM SOUTHEAST. TO LEFT, SAMPLING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    46. VIEW OF SAMPLING ROOM FROM SOUTHEAST. TO LEFT, SAMPLING ELEVATOR AND IN CENTER, SAMPLE BINS WITH DISCHARGE CHUTE AND THREE LABELS. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  4. GROUND WATER SAMPLING FOR VOCS

    EPA Science Inventory

    Sampling protocol should be dictated by the sampling objective(s). It is important to obtain representative ground water samples, regardless of the sampling objective(s). Low-flow (minimum draw-down) purging and sampling techniques are best in most instances, particularly for VOC...

  5. Global atmospheric sampling program

    NASA Technical Reports Server (NTRS)

    Lezberg, E. A.; Perkins, P. J.; Englund, D. R.; Gauntner, D. J.; Holdeman, J. D.

    1977-01-01

    Automated instruments were installed on a commercial B-747 aircraft, during the program, to obtain baseline data and to monitor key atmospheric constituents associated with emissions of aircraft engines in order to determine if aircraft are contributing to pollution of the upper atmosphere. Data thus acquired on a global basis over the commercial air routes for 5 to 10 years will be analyzed. Ozone measurements in the 29,000 to 45,000 foot altitude were expanded over what has been available from ozonesondes. Limited aerosol composition measurements from filter samples show low levels of sulfates and nitrates in the upper troposphere. Recently installed instruments for measurement of carbon monoxide and condensation nuclei are beginning to return data.

  6. Stratospheric CCN sampling program

    NASA Technical Reports Server (NTRS)

    Rogers, C. F.

    1981-01-01

    When Mt. St. Helens produced several major eruptions in the late spring of 1980, there was a strong interest in the characterization of the cloud condensation nuclei (CCN) activity of the material that was injected into the troposphere and stratosphere. The scientific value of CCN measurements is two fold: CCN counts may be directly applied to calculations of the interaction of the aerosol (enlargement) at atmospherically-realistic relative humidities or supersaturations; and if the chemical constituency of the aerosol can be assumed, the number-versus-critical supersaturation spectrum may be converted into a dry aerosol size spectrum covering a size region not readily measured by other methods. The sampling method is described along with the instrumentation used in the experiments.

  7. Revisiting sample entropy analysis

    NASA Astrophysics Data System (ADS)

    Govindan, R. B.; Wilson, J. D.; Eswaran, H.; Lowery, C. L.; Preißl, H.

    2007-03-01

    We modify the definition of sample entropy (SaEn) by incorporating a time delay between the components of the block (from which the densities are estimated) and show that the modified method characterizes the complexity of the system better than the original version. We apply the modified SaEn to the standard deterministic systems and stochastic processes (uncorrelated and long range correlated (LRC) processes) and show that the underlying complexity of the system is better quantified by the modified method. We extend this analysis to the RR intervals of the normal and congestive heart failure (CHF) subjects (available via www.physionet.org) and show that there is a good degree of separation between the two groups.

  8. Fluid sampling tool

    DOEpatents

    Johnston, Roger G.; Garcia, Anthony R. E.; Martinez, Ronald K.

    2001-09-25

    The invention includes a rotatable tool for collecting fluid through the wall of a container. The tool includes a fluid collection section with a cylindrical shank having an end portion for drilling a hole in the container wall when the tool is rotated, and a threaded portion for tapping the hole in the container wall. A passageway in the shank in communication with at least one radial inlet hole in the drilling end and an opening at the end of the shank is adapted to receive fluid from the container. The tool also includes a cylindrical chamber affixed to the end of the shank opposite to the drilling portion thereof for receiving and storing fluid passing through the passageway. The tool also includes a flexible, deformable gasket that provides a fluid-tight chamber to confine kerf generated during the drilling and tapping of the hole. The invention also includes a fluid extractor section for extracting fluid samples from the fluid collecting section.

  9. Glass sample characterization

    NASA Technical Reports Server (NTRS)

    Ahmad, Anees

    1990-01-01

    The development of in-house integrated optical performance modelling capability at MSFC is described. This performance model will take into account the effects of structural and thermal distortions, as well as metrology errors in optical surfaces to predict the performance of large an complex optical systems, such as Advanced X-Ray Astrophysics Facility. The necessary hardware and software were identified to implement an integrated optical performance model. A number of design, development, and testing tasks were supported to identify the debonded mirror pad, and rebuilding of the Technology Mirror Assembly. Over 300 samples of Zerodur were prepared in different sizes and shapes for acid etching, coating, and polishing experiments to characterize the subsurface damage and stresses produced by the grinding and polishing operations.

  10. Sub-Nyquist Sampling

    NASA Astrophysics Data System (ADS)

    Mishali, Moshe; Eldar, Yonina

    2011-11-01

    In this article, we review sampling strategies that target reduction of the ADC rate below Nyquist. Our survey covers classic works from the early 1950s through recent publications from the past several years. The prime focus is bridging theory and practice, that is, to pinpoint the potential of sub-Nyquist strategies to emerge from the math to the hardware. In this spirit, we integrate contemporary theoretical viewpoints, which study signal modeling in a union of subspaces, together with a taste of practical aspects, more specifically how the avant-garde modalities boil down to concrete signal processing systems. Our hope is that this presentation style will attract the interest of both researchers and engineers with the aim of promoting the sub-Nyquist premise into practical applications while encouraging further research into this exciting new frontier.

  11. Samples from Asteroid Itokawa

    NASA Astrophysics Data System (ADS)

    Taylor, G. J.; Martel, L. M. V.

    2011-08-01

    The Hayabusa spacecraft, flown by the Japanese Aerospace Exploration Agency (JAXA), returned samples from asteroid 25143 Itokawa on June 13, 2010. Though the sampling device did not operate properly, the mission was able to return a couple thousand particles, from a few- to a few hundred-micrometers across. A battery of laboratory analyses (electron microscopy, elemental analysis, and oxygen isotopic measurements) shows that the particles derive from materials like those in thermally metamorphosed LL group ordinary chondrites. Astronomical observations had classified Itokawa as a stony S(IV) type of asteroid. The nature of S-type asteroids has been debated for decades; some astronomers argued that S-type asteroids are ordinary chondrites while others suggested that they were more likely to be differentiated objects (i.e., melted or partially melted to make igneous rocks). The problem was that we did not know enough about space weathering on asteroids to know how the spectra of chondritic or differentiated asteroids changed with exposure to micrometeorites and solar wind. The examinations of Hayabusa's treasure have settled the argument: S-type asteroid, Itokawa, indeed has an ordinary chondrite composition whose spectrum has been reddened by space weathering. This conclusion is supported by detailed studies of the surfaces of 10 Itokawa particles, half of which have glassy rims (5-50 nanometers thick) containing nano-sized particles of iron sulfide and metallic iron, signatures of space weathering. Analysis of noble gases in three particles from the asteroid indicate that they were exposed on the surface of Itokawa for surprisingly short times, less than 8 million years. The Hayabusa science team suggests that the short exposure time indicates loss of particles into space through small impacts at the surprisingly fast rate of tens of centimeters per million years. This might not seem fast, but the asteroid, only 535 x 294 x 209 meters in size, would become just a

  12. Sample introducing apparatus and sample modules for mass spectrometer

    DOEpatents

    Thompson, Cyril V.; Wise, Marcus B.

    1993-01-01

    An apparatus for introducing gaseous samples from a wide range of environmental matrices into a mass spectrometer for analysis of the samples is described. Several sample preparing modules including a real-time air monitoring module, a soil/liquid purge module, and a thermal desorption module are individually and rapidly attachable to the sample introducing apparatus for supplying gaseous samples to the mass spectrometer. The sample-introducing apparatus uses a capillary column for conveying the gaseous samples into the mass spectrometer and is provided with an open/split interface in communication with the capillary and a sample archiving port through which at least about 90 percent of the gaseous sample in a mixture with an inert gas that was introduced into the sample introducing apparatus is separated from a minor portion of the mixture entering the capillary discharged from the sample introducing apparatus.

  13. Sample introducing apparatus and sample modules for mass spectrometer

    DOEpatents

    Thompson, C.V.; Wise, M.B.

    1993-12-21

    An apparatus for introducing gaseous samples from a wide range of environmental matrices into a mass spectrometer for analysis of the samples is described. Several sample preparing modules including a real-time air monitoring module, a soil/liquid purge module, and a thermal desorption module are individually and rapidly attachable to the sample introducing apparatus for supplying gaseous samples to the mass spectrometer. The sample-introducing apparatus uses a capillary column for conveying the gaseous samples into the mass spectrometer and is provided with an open/split interface in communication with the capillary and a sample archiving port through which at least about 90 percent of the gaseous sample in a mixture with an inert gas that was introduced into the sample introducing apparatus is separated from a minor portion of the mixture entering the capillary discharged from the sample introducing apparatus. 5 figures.

  14. Soil sampling kit and a method of sampling therewith

    DOEpatents

    Thompson, C.V.

    1991-02-05

    A soil sampling device and a sample containment device for containing a soil sample is disclosed. In addition, a method for taking a soil sample using the soil sampling device and soil sample containment device to minimize the loss of any volatile organic compounds contained in the soil sample prior to analysis is disclosed. The soil sampling device comprises two close fitting, longitudinal tubular members of suitable length, the inner tube having the outward end closed. With the inner closed tube withdrawn a selected distance, the outer tube can be inserted into the ground or other similar soft material to withdraw a sample of material for examination. The inner closed end tube controls the volume of the sample taken and also serves to eject the sample. The soil sample containment device has a sealing member which is adapted to attach to an analytical apparatus which analyzes the volatile organic compounds contained in the sample. The soil sampling device in combination with the soil sample containment device allows an operator to obtain a soil sample containing volatile organic compounds and minimizing the loss of the volatile organic compounds prior to analysis of the soil sample for the volatile organic compounds. 11 figures.

  15. Soil sampling kit and a method of sampling therewith

    DOEpatents

    Thompson, Cyril V.

    1991-01-01

    A soil sampling device and a sample containment device for containing a soil sample is disclosed. In addition, a method for taking a soil sample using the soil sampling device and soil sample containment device to minimize the loss of any volatile organic compounds contained in the soil sample prior to analysis is disclosed. The soil sampling device comprises two close fitting, longitudinal tubular members of suitable length, the inner tube having the outward end closed. With the inner closed tube withdrawn a selected distance, the outer tube can be inserted into the ground or other similar soft material to withdraw a sample of material for examination. The inner closed end tube controls the volume of the sample taken and also serves to eject the sample. The soil sample containment device has a sealing member which is adapted to attach to an analytical apparatus which analyzes the volatile organic compounds contained in the sample. The soil sampling device in combination with the soil sample containment device allow an operator to obtain a soil sample containing volatile organic compounds and minimizing the loss of the volatile organic compounds prior to analysis of the soil sample for the volatile organic compounds.

  16. COMPOSITE SAMPLING FOR ENVIRONMENTAL MONITORING

    EPA Science Inventory

    Guidance for selecting a plan to tomposite environmental or biological samples is provided in the form of models, equations, tables, and criteria. Composite sampling procedures can increase sensitivity, reduce sampling variance, and dramatically reduce analytical costs, depending...

  17. Fluid sampling apparatus and method

    DOEpatents

    Yeamans, David R.

    1998-01-01

    Incorporation of a bellows in a sampling syringe eliminates ingress of contaminants, permits replication of amounts and compression of multiple sample injections, and enables remote sampling for off-site analysis.

  18. Fluid sampling apparatus and method

    DOEpatents

    Yeamans, D.R.

    1998-02-03

    Incorporation of a bellows in a sampling syringe eliminates ingress of contaminants, permits replication of amounts and compression of multiple sample injections, and enables remote sampling for off-site analysis. 3 figs.

  19. Bacterial community composition of chronic periodontitis and novel oral sampling sites for detecting disease indicators.

    PubMed

    Galimanas, Vaia; Hall, Michael William; Singh, Natasha; Lynch, Michael David Joseph; Goldberg, Michael; Tenenbaum, Howard; Cvitkovitch, Dennis Gerard; Neufeld, Josh David; Senadheera, Dilani Braziunas

    2014-01-01

    Periodontitis is an infectious and inflammatory disease of polymicrobial etiology that can lead to the destruction of bones and tissues that support the teeth. The management of chronic periodontitis (CP) relies heavily on elimination or at least control of known pathogenic consortia associated with the disease. Until now, microbial plaque obtained from the subgingival (SubG) sites has been the primary focus for bacterial community analysis using deep sequencing. In addition to the use of SubG plaque, here, we investigated whether plaque obtained from supragingival (SupG) and tongue dorsum sites can serve as alternatives for monitoring CP-associated bacterial biomarkers. Using SubG, SupG, and tongue plaque DNA from 11 healthy and 13 diseased subjects, we sequenced V3 regions (approximately 200 bases) of the 16S rRNA gene using Illumina sequencing. After quality filtering, approximately 4.1 million sequences were collapsed into operational taxonomic units (OTUs; sequence identity cutoff of >97%) that were classified to a total of 19 phyla spanning 114 genera. Bacterial community diversity and overall composition was not affected by health or disease, and multiresponse permutation procedure (MRPP) on Bray-Curtis distance measures only supported weakly distinct bacterial communities in SubG and tongue plaque depending on health or disease status (P < 0.05). Nonetheless, in SubG and tongue sites, the relative abundance of Firmicutes was increased significantly from health to disease and members of Synergistetes were found in higher abundance across all sites in disease. Taxa indicative of CP were identified in all three locations (for example, Treponema denticola, Porphyromonas gingivalis, Synergistes oral taxa 362 and 363). For the first time, this study demonstrates that SupG and tongue dorsum plaque can serve as alternative sources for detecting and enumerating known and novel bacterial biomarkers of CP. This finding is clinically important because, in contrast

  20. Bacterial community composition of chronic periodontitis and novel oral sampling sites for detecting disease indicators

    PubMed Central

    2014-01-01

    Background Periodontitis is an infectious and inflammatory disease of polymicrobial etiology that can lead to the destruction of bones and tissues that support the teeth. The management of chronic periodontitis (CP) relies heavily on elimination or at least control of known pathogenic consortia associated with the disease. Until now, microbial plaque obtained from the subgingival (SubG) sites has been the primary focus for bacterial community analysis using deep sequencing. In addition to the use of SubG plaque, here, we investigated whether plaque obtained from supragingival (SupG) and tongue dorsum sites can serve as alternatives for monitoring CP-associated bacterial biomarkers. Results Using SubG, SupG, and tongue plaque DNA from 11 healthy and 13 diseased subjects, we sequenced V3 regions (approximately 200 bases) of the 16S rRNA gene using Illumina sequencing. After quality filtering, approximately 4.1 million sequences were collapsed into operational taxonomic units (OTUs; sequence identity cutoff of >97%) that were classified to a total of 19 phyla spanning 114 genera. Bacterial community diversity and overall composition was not affected by health or disease, and multiresponse permutation procedure (MRPP) on Bray-Curtis distance measures only supported weakly distinct bacterial communities in SubG and tongue plaque depending on health or disease status (P < 0.05). Nonetheless, in SubG and tongue sites, the relative abundance of Firmicutes was increased significantly from health to disease and members of Synergistetes were found in higher abundance across all sites in disease. Taxa indicative of CP were identified in all three locations (for example, Treponema denticola, Porphyromonas gingivalis, Synergistes oral taxa 362 and 363). Conclusions For the first time, this study demonstrates that SupG and tongue dorsum plaque can serve as alternative sources for detecting and enumerating known and novel bacterial biomarkers of CP. This finding is clinically

  1. Considerations in sampling of water.

    PubMed

    Ramsey, Charles A

    2015-01-01

    Sampling water is no different than sampling any other media. It starts with the development of Sample Quality Criteria, understanding of material properties, then application of the Theory of Sampling. The main difference with sampling water as opposed to solids is the material properties. This paper addresses some of the material properties and consequences of those properties for the development of the sampling protocols. Two properties that must be addressed for water are the temporal nature and the inclusion of suspended solids. Examples are provided for three specific water sampling scenarios which may have application to other water sampling scenarios.

  2. Variable Sampling Mapping

    NASA Technical Reports Server (NTRS)

    Smith, Jeffrey, S.; Aronstein, David L.; Dean, Bruce H.; Lyon, Richard G.

    2012-01-01

    The performance of an optical system (for example, a telescope) is limited by the misalignments and manufacturing imperfections of the optical elements in the system. The impact of these misalignments and imperfections can be quantified by the phase variations imparted on light traveling through the system. Phase retrieval is a methodology for determining these variations. Phase retrieval uses images taken with the optical system and using a light source of known shape and characteristics. Unlike interferometric methods, which require an optical reference for comparison, and unlike Shack-Hartmann wavefront sensors that require special optical hardware at the optical system's exit pupil, phase retrieval is an in situ, image-based method for determining the phase variations of light at the system s exit pupil. Phase retrieval can be used both as an optical metrology tool (during fabrication of optical surfaces and assembly of optical systems) and as a sensor used in active, closed-loop control of an optical system, to optimize performance. One class of phase-retrieval algorithms is the iterative transform algorithm (ITA). ITAs estimate the phase variations by iteratively enforcing known constraints in the exit pupil and at the detector, determined from modeled or measured data. The Variable Sampling Mapping (VSM) technique is a new method for enforcing these constraints in ITAs. VSM is an open framework for addressing a wide range of issues that have previously been considered detrimental to high-accuracy phase retrieval, including undersampled images, broadband illumination, images taken at or near best focus, chromatic aberrations, jitter or vibration of the optical system or detector, and dead or noisy detector pixels. The VSM is a model-to-data mapping procedure. In VSM, fully sampled electric fields at multiple wavelengths are modeled inside the phase-retrieval algorithm, and then these fields are mapped to intensities on the light detector, using the properties

  3. [A comparison of convenience sampling and purposive sampling].

    PubMed

    Suen, Lee-Jen Wu; Huang, Hui-Man; Lee, Hao-Hsien

    2014-06-01

    Convenience sampling and purposive sampling are two different sampling methods. This article first explains sampling terms such as target population, accessible population, simple random sampling, intended sample, actual sample, and statistical power analysis. These terms are then used to explain the difference between "convenience sampling" and purposive sampling." Convenience sampling is a non-probabilistic sampling technique applicable to qualitative or quantitative studies, although it is most frequently used in quantitative studies. In convenience samples, subjects more readily accessible to the researcher are more likely to be included. Thus, in quantitative studies, opportunity to participate is not equal for all qualified individuals in the target population and study results are not necessarily generalizable to this population. As in all quantitative studies, increasing the sample size increases the statistical power of the convenience sample. In contrast, purposive sampling is typically used in qualitative studies. Researchers who use this technique carefully select subjects based on study purpose with the expectation that each participant will provide unique and rich information of value to the study. As a result, members of the accessible population are not interchangeable and sample size is determined by data saturation not by statistical power analysis.

  4. Sample Manipulation System for Sample Analysis at Mars

    NASA Technical Reports Server (NTRS)

    Mumm, Erik; Kennedy, Tom; Carlson, Lee; Roberts, Dustyn

    2008-01-01

    The Sample Analysis at Mars (SAM) instrument will analyze Martian samples collected by the Mars Science Laboratory Rover with a suite of spectrometers. This paper discusses the driving requirements, design, and lessons learned in the development of the Sample Manipulation System (SMS) within SAM. The SMS stores and manipulates 74 sample cups to be used for solid sample pyrolysis experiments. Focus is given to the unique mechanism architecture developed to deliver a high packing density of sample cups in a reliable, fault tolerant manner while minimizing system mass and control complexity. Lessons learned are presented on contamination control, launch restraint mechanisms for fragile sample cups, and mechanism test data.

  5. Quantum Metropolis sampling.

    PubMed

    Temme, K; Osborne, T J; Vollbrecht, K G; Poulin, D; Verstraete, F

    2011-03-03

    The original motivation to build a quantum computer came from Feynman, who imagined a machine capable of simulating generic quantum mechanical systems--a task that is believed to be intractable for classical computers. Such a machine could have far-reaching applications in the simulation of many-body quantum physics in condensed-matter, chemical and high-energy systems. Part of Feynman's challenge was met by Lloyd, who showed how to approximately decompose the time evolution operator of interacting quantum particles into a short sequence of elementary gates, suitable for operation on a quantum computer. However, this left open the problem of how to simulate the equilibrium and static properties of quantum systems. This requires the preparation of ground and Gibbs states on a quantum computer. For classical systems, this problem is solved by the ubiquitous Metropolis algorithm, a method that has basically acquired a monopoly on the simulation of interacting particles. Here we demonstrate how to implement a quantum version of the Metropolis algorithm. This algorithm permits sampling directly from the eigenstates of the Hamiltonian, and thus evades the sign problem present in classical simulations. A small-scale implementation of this algorithm should be achievable with today's technology.

  6. Sample preparation techniques.

    PubMed

    Baumgartner, W A; Hill, V A

    1993-12-01

    Evidentiary false positives are caused by passive exposure to drugs in the environment rather than by active use of drugs. The avoidance of such positives is essential for both hair and urine analysis. Hair analysis enjoys the advantage over urinalysis in having a number of approaches for making this distinction. These include: methylene blue staining of the hair specimen for selecting the appropriate wash solvent; application of hair digestion techniques for the complete release of chemically unaltered analytes; the determination of three diagnostic ratios from wash and digestion data; the measurement of metabolite:drug ratios; the use of cut-off levels setting the limits for passive endogenous drug exposure; reproducibility of results (including segmental analysis) with a newly collected hair specimen; and the reporting of results as either negative, positive, or contaminated. Our sample preparation procedures have been effectively applied to the analyses of nearly 200,000 specimens, i.e. to approximately one million drug analyses for cocaine, opiates, methamphetamine, phencyclidine or marijuana. On the basis of this experience we conclude that hair analysis is a safe and effective method for workplace drug testing.

  7. TEMPUS Experiment Sample

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This metal sample, which is approximately 1 cm in diameter, is typical of the metals that were studied using the German designed electromagnetic containerless processing facility. The series of experiments that use this device is known as TEMPUS which is the acronym that stands for the German Tiegelfreies Elektromanetisches Prozessieren Unter Schwerelosigkeit. Most of the TEMPUS experiments focused on various aspects of undercooling liquid metal and alloys. Undercooling is the process of melting a material and then cooling it to a temperature that is below its normal freezing or solidification point. The TEMPUS experiments that used the metal cages as shown in the photograph, often studied bulk metallic glass, a solid material with no crystalline structures. We study metals and alloys not only to build things in space, but to improve things that are made on Earth. Metals and alloys are everywhere around us; in our automobiles, in the engines of aircraft, in our power-plants, and elsewhere. Despite their presence in everyday life, there are many scientific aspects of metals that we do not understand.

  8. Sample holder with optical features

    DOEpatents

    Milas, Mirko; Zhu, Yimei; Rameau, Jonathan David

    2013-07-30

    A sample holder for holding a sample to be observed for research purposes, particularly in a transmission electron microscope (TEM), generally includes an external alignment part for directing a light beam in a predetermined beam direction, a sample holder body in optical communication with the external alignment part and a sample support member disposed at a distal end of the sample holder body opposite the external alignment part for holding a sample to be analyzed. The sample holder body defines an internal conduit for the light beam and the sample support member includes a light beam positioner for directing the light beam between the sample holder body and the sample held by the sample support member.

  9. Subsurface Samples: Collection and Processing

    SciTech Connect

    Long, Philip E.; Griffin, W. Timothy; Phelps, Tommy J.

    2002-12-01

    Microbiological data, interpretation, and conclusions from subsurface samples ultimately depend on the quality and representative character of the samples. Subsurface samples for environmental microbiology ideally contain only the microbial community and geochemical properties that are representative of the subsurface environment from which the sample was taken. To that end, sample contamination by exogenous microorganisms or chemical constituents must be eliminated or minimized, and sample analyses need to begin before changes in the microbial community or geochemical characteristics occur. This article presents sampling methods and sample processing techniques for collecting representative samples from a range of subsurface environments. Factors that should be considered when developing a subsurface sampling program are discussed, including potential benefits, costs, and limitations enabling researchers to evaluate the techniques that are presented and match them to their project requirements. Methods and protocols to address coring, sampling, processing and quality assessment issues are presented.

  10. Deterministic multidimensional nonuniform gap sampling.

    PubMed

    Worley, Bradley; Powers, Robert

    2015-12-01

    Born from empirical observations in nonuniformly sampled multidimensional NMR data relating to gaps between sampled points, the Poisson-gap sampling method has enjoyed widespread use in biomolecular NMR. While the majority of nonuniform sampling schemes are fully randomly drawn from probability densities that vary over a Nyquist grid, the Poisson-gap scheme employs constrained random deviates to minimize the gaps between sampled grid points. We describe a deterministic gap sampling method, based on the average behavior of Poisson-gap sampling, which performs comparably to its random counterpart with the additional benefit of completely deterministic behavior. We also introduce a general algorithm for multidimensional nonuniform sampling based on a gap equation, and apply it to yield a deterministic sampling scheme that combines burst-mode sampling features with those of Poisson-gap schemes. Finally, we derive a relationship between stochastic gap equations and the expectation value of their sampling probability densities. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Systematic sampling for suspended sediment

    Treesearch

    Robert B. Thomas

    1991-01-01

    Abstract - Because of high costs or complex logistics, scientific populations cannot be measured entirely and must be sampled. Accepted scientific practice holds that sample selection be based on statistical principles to assure objectivity when estimating totals and variances. Probability sampling--obtaining samples with known probabilities--is the only method that...

  12. Dimensionality and the sample unit

    Treesearch

    Francis A. Roesch

    2009-01-01

    The sample unit and its implications for the Forest Service, U.S. Department of Agriculture's Forest Inventory and Analysis program are discussed in light of a generalized three-dimensional concept of continuous forest inventories. The concept views the sampled population as a spatial-temporal cube and the sample as a finite partitioning of the cube. The sample...

  13. Importance sampling : promises and limitations.

    SciTech Connect

    West, Nicholas J.; Swiler, Laura Painton

    2010-04-01

    Importance sampling is an unbiased sampling method used to sample random variables from different densities than originally defined. These importance sampling densities are constructed to pick 'important' values of input random variables to improve the estimation of a statistical response of interest, such as a mean or probability of failure. Conceptually, importance sampling is very attractive: for example one wants to generate more samples in a failure region when estimating failure probabilities. In practice, however, importance sampling can be challenging to implement efficiently, especially in a general framework that will allow solutions for many classes of problems. We are interested in the promises and limitations of importance sampling as applied to computationally expensive finite element simulations which are treated as 'black-box' codes. In this paper, we present a customized importance sampler that is meant to be used after an initial set of Latin Hypercube samples has been taken, to help refine a failure probability estimate. The importance sampling densities are constructed based on kernel density estimators. We examine importance sampling with respect to two main questions: is importance sampling efficient and accurate for situations where we can only afford small numbers of samples? And does importance sampling require the use of surrogate methods to generate a sufficient number of samples so that the importance sampling process does increase the accuracy of the failure probability estimate? We present various case studies to address these questions.

  14. Preservation of Liquid Biological Samples

    NASA Technical Reports Server (NTRS)

    Putcha, Lakshmi (Inventor); Nimmagudda, Ramalingeshwara R. (Inventor)

    2000-01-01

    The present invention provides a method of preserving a liquid biological sample, comprising the step of: contacting said liquid biological sample with a preservative comprising, sodium benzoate in an amount of at least about 0.15% of the sample (weight/volume) and citric acid in an amount of at least about 0.025% of the sample (weight/volume).

  15. Nonuniform sampling and spectral aliasing

    NASA Astrophysics Data System (ADS)

    Maciejewski, Mark W.; Qui, Harry Z.; Rujan, Iulian; Mobli, Mehdi; Hoch, Jeffrey C.

    2009-07-01

    The Nyquist theorem stipulates the largest sampling interval sufficient to avoid aliasing is the reciprocal of the spectral bandwidth. When data are not sampled uniformly, the Nyquist theorem no longer applies, and aliasing phenomena become more complex. For samples selected from an evenly spaced grid, signals that are within the nominal bandwidth of the grid can give rise to aliases. The effective bandwidth afforded by a set of nonuniformly sampled evolution times does not necessarily correspond to spacing of the grid from which the samples are selected, but instead depends on the actual distribution of sample times. For conventional uniform sampling there is no distinction between the grid spacing and the sampling interval. For nonuniform sampling, an effective bandwidth can be inferred from the greatest common divisor of the sample times, provided that none of the sample times are irrational. A simple way to increase the effective bandwidth for a set of nonuniformly spaced samples is to randomly select them from an oversampled grid. For a given grid spacing, "bursty" sampling helps to minimize aliasing artifacts. We show that some spectral artifacts arising from nonuniform sampling are aliases, and that increasing the effective bandwidth shifts these artifacts out of the spectral window and improves spectral quality. An advantage of nonuniform sampling is that some of the benefits of oversampling can be realized without incurring experiment time or resolution penalties. We illustrate the improvements that can be obtained with nonuniform sampling in the indirect dimension of a SOFAST-HMQC experiment.

  16. How Many Samples are Needed

    DTIC Science & Technology

    2011-03-29

    if the sampling grid pattern or the regular frequency of taking samples coincides with any pattern of contamination 61 Example: Littlewood Site...Conclusion for Littlewood 71 Need 22 + 4 = 26 samples for Production Area Need 5 + 1 = 6 samples for Parking/Admin As the budget allowed

  17. Preservation of Liquid Biological Samples

    NASA Technical Reports Server (NTRS)

    Putcha, Lakshmi (Inventor); Nimmagudda, Ramalingeshwara (Inventor)

    2004-01-01

    The present invention related to the preservation of a liquid biological sample. The biological sample is exposed to a preservative containing at least about 0.15 g of sodium benzoate and at least about 0.025 g of citric acid per 100 ml of sample. The biological sample may be collected in a vessel or an absorbent mass. The biological sample may also be exposed to a substrate and/or a vehicle.

  18. Adaptive sampling in behavioral surveys.

    PubMed

    Thompson, S K

    1997-01-01

    Studies of populations such as drug users encounter difficulties because the members of the populations are rare, hidden, or hard to reach. Conventionally designed large-scale surveys detect relatively few members of the populations so that estimates of population characteristics have high uncertainty. Ethnographic studies, on the other hand, reach suitable numbers of individuals only through the use of link-tracing, chain referral, or snowball sampling procedures that often leave the investigators unable to make inferences from their sample to the hidden population as a whole. In adaptive sampling, the procedure for selecting people or other units to be in the sample depends on variables of interest observed during the survey, so the design adapts to the population as encountered. For example, when self-reported drug use is found among members of the sample, sampling effort may be increased in nearby areas. Types of adaptive sampling designs include ordinary sequential sampling, adaptive allocation in stratified sampling, adaptive cluster sampling, and optimal model-based designs. Graph sampling refers to situations with nodes (for example, people) connected by edges (such as social links or geographic proximity). An initial sample of nodes or edges is selected and edges are subsequently followed to bring other nodes into the sample. Graph sampling designs include network sampling, snowball sampling, link-tracing, chain referral, and adaptive cluster sampling. A graph sampling design is adaptive if the decision to include linked nodes depends on variables of interest observed on nodes already in the sample. Adjustment methods for nonsampling errors such as imperfect detection of drug users in the sample apply to adaptive as well as conventional designs.

  19. Rapid screening for Mycobacterium tuberculosis complex in clinical elephant trunk wash samples.

    PubMed

    Magnuson, Roberta J; Linke, Lyndsey M; Isaza, Ramiro; Salman, Mo D

    2017-06-01

    Mycobacterium tuberculosis can infect and be transmitted between elephants and humans. In elephants, the 'gold standard' reference test for detection of tuberculosis is culture, which takes a minimum of eight weeks for results and has limited sensitivity. A screening test that is rapid, easily implemented, and accurate is needed to aid in diagnosis of tuberculosis in elephants. Ninety-nine clinical trunk wash samples obtained from 33 elephants were utilized to validate three molecular extraction techniques followed by a polymerase chain reaction for detection of M. tuberculosis. Diagnostic sensitivity and specificity were estimated compared to culture. Kappa coefficients were determined between molecular results and various culture categories and serological test results. An internal amplification control was developed and assessed to monitor for PCR inhibition. One molecular test (the Column method) outperformed the other two, with diagnostic sensitivity and kappa agreement estimates of 100% (CI 57-100) and 0.46 (CI 0.2-0.74), respectively, compared to culture alone. The percentage of molecular-positive/culture-negative samples was 8.4% overall. The molecular extraction technique followed by PCR provides a much-needed rapid screening tool for detection of tuberculosis in elephants. Immediate procedures can be implemented to further assess PCR-positive animals and provide personnel biosecurity. While a positive result is not a definitive test for elephant tuberculosis, the molecular test results can be used to support current diagnostic procedures applied by veterinarians for treatment decisions to prevent the spread of tuberculosis in elephants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Detection of bacterial pathogens from clinical specimens using conventional microbial culture and 16S metagenomics: a comparative study.

    PubMed

    Abayasekara, Lalanika M; Perera, Jennifer; Chandrasekharan, Vishvanath; Gnanam, Vaz S; Udunuwara, Nisala A; Liyanage, Dileepa S; Bulathsinhala, Nuwani E; Adikary, Subhashanie; Aluthmuhandiram, Janith V S; Thanaseelan, Chrishanthi S; Tharmakulasingam, D Portia; Karunakaran, Tharaga; Ilango, Janahan

    2017-09-19

    Infectious disease is the leading cause of death worldwide, and diagnosis of polymicrobial and fungal infections is increasingly challenging in the clinical setting. Conventionally, molecular detection is still the best method of species identification in clinical samples. However, the limitations of Sanger sequencing make diagnosis of polymicrobial infections one of the biggest hurdles in treatment. The development of massively parallel sequencing or next generation sequencing (NGS) has revolutionized the field of metagenomics, with wide application of the technology in identification of microbial communities in environmental sources, human gut and others. However, to date there has been no commercial application of this technology in infectious disease diagnostic settings. Credence Genomics Rapid Infection Detection™ test, is a molecular based diagnostic test that uses next generation sequencing of bacterial 16S rRNA gene and fungal ITS1 gene region to provide accurate identification of species within a clinical sample. Here we present a study comparing 16S and ITS1 metagenomic identification against conventional culture for clinical samples. Using culture results as gold standard, a comparison was conducted using patient specimens from a clinical microbiology lab. Metagenomics based results show a 91.8% concordance rate for culture positive specimens and 52.8% concordance rate with culture negative samples. 10.3% of specimens were also positive for fungal species which was not investigated by culture. Specificity and sensitivity for metagenomics analysis is 91.8 and 52.7% respectively. 16S based metagenomic identification of bacterial species within a clinical specimen is on par with conventional culture based techniques and when coupled with clinical information can lead to an accurate diagnostic tool for infectious disease diagnosis.