scholarly journals Evaluation of Commercial Molecular Diagnostic Methods for Detection and Determination of Macrolide Resistance in Mycoplasma pneumoniae

2020 ◽  
Vol 58 (6) ◽  
Author(s):  
Sixto M. Leal ◽  
Arthur H. Totten ◽  
Li Xiao ◽  
Donna M. Crabb ◽  
Amy Ratliff ◽  
...  
Keyword(s):  
Mycoplasma Pneumoniae ◽  
Large Scale ◽  
The United States ◽  
Macrolide Resistance ◽  
Diagnostic Methods ◽  
Respiratory Pathogen ◽  
Molecular Diagnostic ◽  
Content Type ◽  
Significant Difference ◽  
The Impact

ABSTRACT We evaluated six commercial molecular tests targeting Mycoplasma pneumoniae, namely, the BioFire FilmArray respiratory panel (RP), the Meridian Alethia Mycoplasma Direct, the GenMark ePlex respiratory pathogen panel (RPP), the Luminex NxTAG RPP, the ELITech ELITe InGenius Mycoplasma MGB research use only (RUO) PCR, and the SpeeDx Resistance Plus MP assays. Laboratory-developed PCR assays at the University of Alabama at Birmingham and the Centers for Disease Control and Prevention were used as reference standards. Among 428 specimens, 212 were designated confirmed positives for M. pneumoniae. The highest clinical sensitivities were found with the InGenius PCR (99.5%) and the FilmArray RP (98.1%). The Resistance Plus MP identified 93.3% of the confirmed-positive specimens, whereas 83.6, 64.6, and 55.7% were identified by the ePlex RPP, NxTAG RPP, and Mycoplasma Direct assays, respectively. There was no significant difference between the sensitivity of the reference methods and that of the FilmArray RP and InGenius assays, but the remaining four assays detected significantly fewer positive specimens (P < 0.05). Specificities of all assays were 99.5 to 100%. The Resistance Plus MP assay detected macrolide resistance in 27/33 specimens, resulting in a sensitivity of 81.8%. This study provides the first large-scale comparison of commercial molecular assays for detection of M. pneumoniae in the United States and identified clear differences among their performance. Additional studies are necessary to explore the impact of various test performances on patient outcome.

scholarly journals Molecular Characterization of Mycoplasma pneumoniae Isolates in the United States from 2012 to 2018

2020 ◽  
Vol 58 (10) ◽  
Author(s):  
L. Xiao ◽  
A. E. Ratliff ◽  
D. M. Crabb ◽  
E. Mixon ◽  
X. Qin ◽  
...  
Keyword(s):  
United States ◽  
Mycoplasma Pneumoniae ◽  
Tandem Repeats ◽  
Geographic Location ◽  
The United States ◽  
Resistance Rate ◽  
Macrolide Resistance ◽  
Content Type ◽  
Mlva Type ◽  
Epidemiological Characteristics

ABSTRACT Mycoplasma pneumoniae is a major cause of community-acquired pneumonia. There are limited data in the United States on the molecular epidemiological characteristics of M. pneumoniae. We collected 446 M. pneumoniae-positive specimens from 9 states between August 2012 and October 2018. Culture, antimicrobial susceptibility testing, P1 subtyping, and multilocus VNTR (variable-number tandem repeats) analysis (MLVA) were performed to characterize the isolates. Macrolide-resistant M. pneumoniae (MRMp) was detected in 37 (8.3%) specimens. P1 subtype 2 (P1-2) was the predominant P1 subtype (59.8%). P1 subtype distribution did not change significantly chronologically or geographically. The macrolide resistance rate in P1 subtype 1 (P1-1) samples was significantly higher than that in P1-2 (12.9% versus 5.5%). Six P1-2 variants were identified, including two novel types, and variant 2c was predominant (64.6%). P1-2 variants were distributed significantly differently among geographic regions. Classical P1-2 was more frequent in lower respiratory tract specimens and had longer p1 trinucleotide repeats. Classical P1-2 was most common in MRMp (35.7%), while variant 2c was most common in macrolide-susceptible M. pneumoniae (67.5%). Fifteen MLVA types were identified; 3-5-6-2 (41.7%), 4-5-7-2 (35.3%), and 3-6-6-2 (16.6%) were the major types, and four MLVA clusters were delineated. The distribution of MLVA types varied significantly over time and geographic location. The predominant MLVA type switched from 4-5-7-2 to 3-5-6-2 in 2015. MLVA type was associated with P1 subtypes and P1-2 variant types but not with macrolide resistance. To investigate the M. pneumoniae genotype shift and its impact on clinical presentations, additional surveillance programs targeting more diverse populations and prolonged sampling times are required.

scholarly journals Evaluation of GENECUBE Mycoplasma for the detection of macrolide-resistant Mycoplasma pneumoniae

2020 ◽  
Vol 69 (12) ◽  
pp. 1346-1350
Author(s):  
Yoshitomo Morinaga ◽  
Hiromichi Suzuki ◽  
Shigeyuki Notake ◽  
Takashi Mizusaka ◽  
Keiichi Uemura ◽  
...  
Keyword(s):  
Mycoplasma Pneumoniae ◽  
Type Species ◽  
Resistance Mutation ◽  
Macrolide Resistance ◽  
23S Rrna ◽  
Molecular Diagnostic ◽  
Content Type ◽  
Link Type ◽  
High Level ◽  
Synthetic Oligonucleotides

Introduction. Resistance against macrolide antibiotics in Mycoplasma pneumoniae is becoming non-negligible in terms of both appropriate therapy and diagnostic stewardship. Molecular methods have attractive features for the identification of Mycoplasma pneumoniae as well as its resistance-associated mutations of 23S ribosomal RNA (rRNA). Hypothesis/Gap Statement. The automated molecular diagnostic sytem can identify macrolide-resistant M. pneumoniae . Aim. To assess the performance of an automated molecular diagnostic system, GENECUBE Mycoplasma, in the detection of macrolide resistance-associated mutations. Methodology. To evaluate whether the system can distinguish mutant from wild-type 23S rRNA, synthetic oligonucleotides mimicking known mutations (high-level macrolide resistance, mutation in positions 2063 and 2064; low-level macrolide resistance, mutation in position 2067) were assayed. To evaluate clinical oropharyngeal samples, purified nucleic acids were obtained from M. pneumoniae -positive samples by using the GENECUBE system from nine hospitals. After confirmation by re-evaluation of M. pneumoniae positivity, Sanger-based sequencing of 23S rRNA and mutant typing using GENECUBE Mycoplasma were performed. Results. The system reproducibly identified all synthetic oligonucleotides associated with high-level macrolide resistance. Detection errors were only observed for A2067G (in 2 of the 10 measurements). The point mutation in 23S rRNA was detected in 67 (26.9 %) of 249 confirmed M. pneumoniae -positive clinical samples. The mutations at positions 2063, 2064 and 2617 were observed in 65 (97.0 %), 2 (3.0 %) and 0 (0.0 %) of the 67 samples, respectively. The mutations at positions 2063 and 2064 were A2063G and A2064G, respectively. The results from mutant typing using GENECUBE Mycoplasma were in full agreement with the results from sequence-based typing. Conclusion. GENECUBE Mycoplasma is a reliable test for the identification of clinically significant macrolide-resistant M. pneumoniae .

scholarly journals Comparison of Molecular Characteristics of Mycoplasma pneumoniae Specimens Collected from the United States and China

2015 ◽  
Vol 53 (12) ◽  
pp. 3891-3893 ◽  
Author(s):  
Chao Yan ◽  
Hongmei Sun ◽  
Stella Lee ◽  
Rangaraj Selvarangan ◽  
Xuan Qin ◽  
...  
Keyword(s):  
United States ◽  
Mycoplasma Pneumoniae ◽  
The United States ◽  
Macrolide Resistance ◽  
Molecular Characteristics ◽  
Lower Prevalence ◽  
Content Type ◽  
Clinical Specimens ◽  
The U.S

Mycoplasma pneumoniae-positive clinical specimens obtained from the United States and China during the same period were studied for their molecular characteristics. We found much more diverse genotypes and a lower prevalence of macrolide resistance in the U.S. specimens. Data from the study also showed an association of the resistance with certain genotypes.

scholarly journals Investigations of Mycoplasma pneumoniae Infections in the United States: Trends in Molecular Typing and Macrolide Resistance from 2006 to 2013

2014 ◽  
Vol 53 (1) ◽  
pp. 124-130 ◽  
Author(s):  
Maureen H. Diaz ◽  
Alvaro J. Benitez ◽  
Jonas M. Winchell
Keyword(s):  
United States ◽  
Mycoplasma Pneumoniae ◽  
Diagnostic Testing ◽  
Variable Number Tandem Repeat ◽  
The United States ◽  
Macrolide Resistance ◽  
Severe Illness ◽  
Surveillance Program ◽  
Content Type ◽  
Time Period

Mycoplasma pneumoniaeis a leading cause of respiratory infections, including community-acquired pneumonia (CAP). Currently, pathogen-specific testing is not routinely performed in the primary care setting, and the United States lacks a systematic surveillance program forM. pneumoniae. Documentation of individual cases and clusters typically occurs only when severe illness and/or failure to improve with empirical antibiotic therapy is observed. Outbreaks, some lasting for extended periods and involving a large number of cases, occur regularly. However, many more likely go unrecognized due to the lack of diagnostic testing and structured reporting. We reviewed data from 17 investigations of cases, small clusters, and outbreaks ofM. pneumoniaeinfections that were supported by the Centers for Disease Control and Prevention (CDC) between 2006 and 2013. We examined 199M. pneumoniae-positive specimens collected during this time period in order to identify trends in antimicrobial resistance and circulating types. Overall, macrolide resistance was identified in approximately 10% ofM. pneumoniaeinfections occurring during this time period. Typing of strains revealed cocirculation of multiple multilocus variable-number tandem-repeat analysis (MLVA) and P1 types throughout this period, including diversity in types detected within individual outbreaks. Three MLVA types (4572, 3562, and 3662) accounted for 97% of the infections during the study period. A systematic surveillance program is necessary to understand the burden ofM. pneumoniaedisease in the United States, facilitate case and outbreak identification, and inform appropriate therapeutic and infection control strategies.

The impact of natural disasters on the performance and solvency of US banks

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Thomas Walker ◽  
Yixin Xu ◽  
Dieter Gramlich ◽  
Yunfei Zhao
Keyword(s):  
Natural Disasters ◽  
Financial Institutions ◽  
Large Scale ◽  
State Level ◽  
The United States ◽  
Capital Requirements ◽  
Net Income ◽  
Content Type ◽  
Equity Ratio ◽  
The Impact

PurposeThis paper explores the effect of natural disasters on the profitability and solvency of US banks.Design/methodology/approachEmploying a sample of 187 large-scale natural disasters that occurred in the United States between 2000 and 2014 and a sample of 2,891 banks, we examine whether and how disaster-related damages affect various measures of bank profitability and bank solvency. We differentiate between different types of banks (with local, regional and national operations) based on a breakdown of their state-level deposits and explore the reaction of these banks to damages weighted by the GDP of the states they operate in.FindingsWe find that natural disasters have a pronounced effect on the net-income-to-assets and the net-income-to-equity ratio of banks, as well as the banks' impaired loans and return on average assets. We also observe significant effects on the equity ratio and the tier-1 capital ratio (two solvency measures). Interestingly, the latter are positive for regional banks which appear to benefit from increased customer deposits related to safekeeping, government payments for post-disaster recovery, insurance payouts and decreased withdrawals, while they are significantly negative for banks that operate locally or nationally.Originality/valueWe contribute to the literature by offering various new insights regarding the effects natural disasters have on financial institutions. With climate change-driven natural disasters widely expected to increase both in terms of frequency and severity, their economic fallout is likely to impose an increasing burden on financial institutions. Large, nationally operating banks tend to be well diversified both geographically and in terms of their product offerings. Small, locally operating banks, however, are increasingly at risk – particularly if they operate in disaster-prone areas. Current banking regulations generally do not factor natural disaster risks into their capital requirements. To avoid the next big financial crisis, regulators may want to adjust their reserve requirements by taking this growing risk exposure into consideration.

scholarly journals Impact of a Rapid Diagnostic Meningitis/Encephalitis Panel on Antimicrobial Use and Clinical Outcomes in Children

Antibiotics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 822
Author(s):  
Danielle McDonald ◽  
Christina Gagliardo ◽  
Stephanie Chiu ◽  
M. Cecilia Di Pentima
Keyword(s):  
Antibiotic Therapy ◽  
Secondary Analysis ◽  
Generation Cephalosporin ◽  
Respiratory Pathogen ◽  
Molecular Diagnostic ◽  
Antimicrobial Use ◽  
Rapid Diagnostics ◽  
Days Of Therapy ◽  
Significant Difference ◽  
The Impact

Rapid molecular diagnostic assays are increasingly used to guide effective antimicrobial therapy. Data on their effectiveness to decrease antimicrobial use in children have been limited and varied. We aimed to assess the impact of the implementation of the FilmArray Meningitis Encephalitis Panel (MEP) on antimicrobial use and outcomes in children. In an observational retrospective study performed at Atlantic Health System (NJ), we sought to evaluate the duration of intravenous antibiotic treatment (days of therapy (DoT)) for patients <21 years of age hospitalized and evaluated for presumptive meningitis or encephalitis before and after the introduction of the MEP. A secondary analysis was performed to determine if recovery of a respiratory pathogen influenced DoT. The median duration of antibiotic therapy prior to the implementation of the MEP was 5 DoT (interquartile range (IQR): 3–6) versus 3 DoT (IQR: 1–5) (p < 0.001) when MEP was performed. The impact was greatest on intravenous third-generation cephalosporin and ampicillin use. We found a reduction in the number of inpatient days associated with the MEP. In the regression analysis, a positive respiratory pathogen panel (RPP) was not a significant predictor of DoT (p = 0.08). Furthermore, we found no significant difference between DoT among patients with negative and positive RPP (p = 0.12). Our study supports the implementation of rapid diagnostics to decrease the utilization of antibiotic therapy among pediatric patients admitted with concerns related to meningitis or encephalitis.

Situational Breakdowns

2019 ◽  
Author(s):  
Anne Nassauer
Keyword(s):  
United States ◽  
Large Scale ◽  
Contextual Factors ◽  
The United States ◽  
Social Outcomes ◽  
Dynamic Processes ◽  
Collective Decisions ◽  
Different Types ◽  
The Impact

This book provides an account of how and why routine interactions break down and how such situational breakdowns lead to protest violence and other types of surprising social outcomes. It takes a close-up look at the dynamic processes of how situations unfold and compares their role to that of motivations, strategies, and other contextual factors. The book discusses factors that can draw us into violent situations and describes how and why we make uncommon individual and collective decisions. Covering different types of surprise outcomes from protest marches and uprisings turning violent to robbers failing to rob a store at gunpoint, it shows how unfolding situations can override our motivations and strategies and how emotions and culture, as well as rational thinking, still play a part in these events. The first chapters study protest violence in Germany and the United States from 1960 until 2010, taking a detailed look at what happens between the start of a protest and the eruption of violence or its peaceful conclusion. They compare the impact of such dynamics to the role of police strategies and culture, protesters’ claims and violent motivations, the black bloc and agents provocateurs. The analysis shows how violence is triggered, what determines its intensity, and which measures can avoid its outbreak. The book explores whether we find similar situational patterns leading to surprising outcomes in other types of small- and large-scale events: uprisings turning violent, such as Ferguson in 2014 and Baltimore in 2015, and failed armed store robberies.

scholarly journals Potentiating Effect of Mandelate and Lactate on Chemically Induced Germination in Members of Bacillus cereus Sensu Lato

2017 ◽  
Vol 83 (24) ◽  
Author(s):  
Alistair H. Bishop
Keyword(s):  
Bacillus Cereus ◽  
Large Scale ◽  
Germination Rate ◽  
Dependent Manner ◽  
Clostridium Sporogenes ◽  
Specific Chemical ◽  
Content Type ◽  
Ph Range ◽  
Significant Discovery ◽  
The Impact

ABSTRACT Endospores of the genus Bacillus can be triggered to germinate by a limited number of chemicals. Mandelate had powerful additive effects on the levels and rates of germination produced in non-heat-shocked spores of Bacillus anthracis strain Sterne, Bacillus cereus, and Bacillus thuringiensis when combined with l-alanine and inosine. Mandelate had no germinant effect on its own but was active with these germinants in a dose-dependent manner at concentrations higher than 0.5 mM. The maximum rate and extent of germination were produced in B. anthracis by 100 mM l-alanine with 10 mM inosine; this was equaled by just 25% of these germinants when supplemented with 10 mM mandelate. Half the maximal germination rate was produced by 40% of the optimum germinant concentrations or 15% of them when supplemented with 0.8 mM mandelate. Germination rates in B. thuringiensis were highest around neutrality, but the potentiating effect of mandelate was maintained over a wider pH range than was germination with l-alanine and inosine alone. For all species, lactate also promoted germination in the presence of l-alanine and inosine; this was further increased by mandelate. Ammonium ions also enhanced l-alanine- and inosine-induced germination but only when mandelate was present. In spite of the structural similarities, mandelate did not compete with phenylalanine as a germinant. Mandelate appeared to bind to spores while enhancing germination. There was no effect when mandelate was used in conjunction with nonnutrient germinants. No effect was produced with spores of Bacillus subtilis, Clostridium sporogenes, or C. difficile. IMPORTANCE The number of chemicals that can induce germination in the species related to Bacillus cereus has been defined for many years, and they conform to specific chemical types. Although not a germinant itself, mandelate has a structure that is different from these germination-active compounds, and its addition to this list represents a significant discovery in the fundamental biology of spore germination. This novel activity may also have important applied relevance given the impact of spores of B. cereus in foodborne disease and B. anthracis as a threat agent. The destruction of spores of B. anthracis, for example, particularly over large outdoor areas, poses significant scientific and logistical problems. The addition of mandelate and lactate to the established mixtures of l-alanine and inosine would decrease the amount of the established germinants required and increase the speed and level of germination achieved. The large-scale application of “germinate to decontaminate” strategy may thus become more practicable.

Analytical redefinition of DOL and managerial investment decisions

2014 ◽  
Vol 40 (7) ◽  
pp. 734-754 ◽  
Author(s):  
Yoram Kroll ◽  
David Yechiam Aharon
Keyword(s):  
Large Scale ◽  
Investment Decision ◽  
Production Level ◽  
Fixed Cost ◽  
Theoretical Formulation ◽  
Optimal Production ◽  
Demand Shocks ◽  
Content Type ◽  
Operating Leverage ◽  
The Impact

Purpose – The purpose of this paper is to develop alternative analytical measures for the degree of operating leverage (DOL) that reflect the impact of uncertain demand shocks in the product's market on optimal production levels, sales and profits of the firm. Design/methodology/approach – The elasticity measures are constructed according to a theoretical formulation of optimal production level that corresponds to demand shocks for given predetermined levels of fixed cost. Findings – The paper suggests two main findings. First, the analytical marginal DOL is at least twice the traditional DOL depending on the structure of the shock, the production function and demand's elasticity. The traditional DOL is equal to the measure only when large-scale negative demand prompts the firm to abandon production. Second, the paper also provides an analytical measure of DOL in terms of elasticity of profit to sales rather than to production level. Both theoretically and empirically elasticity of profit to sales can be better measured and better reflects risk. Research limitations/implications – This paper should be extended to encompass multiple shocks on demand and supply while investigating the empirical multi variants distribution of the shocks. Practical implications – The model can be used by managers who are well informed about the fixed and variable costs of their firm. The model determines the mean profit- risk trade off which is an important factor in all investment decision problems. Originality/value – Surprisingly and according to the best knowledge, this paper is the first attempt in the literature for alternative analytical DOLs’ formulations that is coherent with basic economic theories of optimal production level under risk.

scholarly journals Lianas reduce carbon accumulation and storage in tropical forests

2015 ◽  
Vol 112 (43) ◽  
pp. 13267-13271 ◽  
Author(s):  
Geertje M. F. van der Heijden ◽  
Jennifer S. Powers ◽  
Stefan A. Schnitzer
Keyword(s):  
Tropical Forests ◽  
Large Scale ◽  
Net Primary Production ◽  
Carbon Dynamics ◽  
Carbon Accumulation ◽  
Carbon Uptake ◽  
Woody Vines ◽  
Significant Difference ◽  
Agent Of Change ◽  
The Impact

Tropical forests store vast quantities of carbon, account for one-third of the carbon fixed by photosynthesis, and are a major sink in the global carbon cycle. Recent evidence suggests that competition between lianas (woody vines) and trees may reduce forest-wide carbon uptake; however, estimates of the impact of lianas on carbon dynamics of tropical forests are crucially lacking. Here we used a large-scale liana removal experiment and found that, at 3 y after liana removal, lianas reduced net above-ground carbon uptake (growth and recruitment minus mortality) by ∼76% per year, mostly by reducing tree growth. The loss of carbon uptake due to liana-induced mortality was four times greater in the control plots in which lianas were present, but high variation among plots prevented a significant difference among the treatments. Lianas altered how aboveground carbon was stored. In forests where lianas were present, the partitioning of forest aboveground net primary production was dominated by leaves (53.2%, compared with 39.2% in liana-free forests) at the expense of woody stems (from 28.9%, compared with 43.9%), resulting in a more rapid return of fixed carbon to the atmosphere. After 3 y of experimental liana removal, our results clearly demonstrate large differences in carbon cycling between forests with and without lianas. Combined with the recently reported increases in liana abundance, these results indicate that lianas are an important and increasing agent of change in the carbon dynamics of tropical forests.

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