ABSTRACT
Pseudomonas aeruginosa harboring Verona Integron-encoded metallo-ß-lactamase enzymes (VIM-CRPA) have been associated with infection outbreaks in several parts of the world. In the US, however, VIM-CRPA remain rare. Starting in December 2018, we identified a cluster of cases in our institution. Herein, we present our epidemiological investigation and strategies to control/manage these challenging infections. This study was conducted in a large academic healthcare system in Miami, FL, between December 2018 and January 2022. Patients were prospectively identified via rapid molecular diagnostics when cultures revealed carbapenem-resistant P. aeruginosa. Alerts were received in real time by the antimicrobial stewardship program and infection prevention teams. Upon alert recognition, a series of interventions were performed as a coordinated effort. A retrospective chart review was conducted to collect patient demographics, antimicrobial therapy, and clinical outcomes. Thirty-nine VIM-CRPA isolates led to infection in 21 patients. The majority were male (76.2%); the median age was 52 years. The majority were mechanically ventilated (n = 15/21; 71.4%); 47.6% (n = 10/21) received renal replacement therapy at the time of index culture. Respiratory (n = 20/39; 51.3%) or bloodstream (n = 13/39; 33.3%) were the most common sources. Most infections (n = 23/37; 62.2%) were treated with an aztreonam-avibactam regimen. Six patients (28.6%) expired within 30 days of index VIM-CRPA infection. Fourteen isolates were selected for whole genome sequencing. Most of them belonged to ST111 (12/14), and they all carried blaVIM-2 chromosomally. This report describes the clinical experience treating serious VIM-CRPA infections with either aztreonam-ceftazidime/avibactam or cefiderocol in combination with other agents. The importance of implementing infection prevention strategies to curb VIM-CRPA outbreaks is also demonstrated.
Subject(s)
Anti-Bacterial Agents , Microbial Sensitivity Tests , Pseudomonas Infections , Pseudomonas aeruginosa , beta-Lactamases , Adult , Female , Humans , Male , Middle Aged , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology , Antimicrobial Stewardship , Azabicyclo Compounds/therapeutic use , Aztreonam/therapeutic use , Aztreonam/pharmacology , beta-Lactamases/genetics , Carbapenems/therapeutic use , Carbapenems/pharmacology , Ceftazidime/therapeutic use , Ceftazidime/pharmacology , Drug Combinations , Drug Resistance, Multiple, Bacterial/genetics , Integrons/genetics , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/genetics , Pseudomonas Infections/drug therapy , Pseudomonas Infections/microbiology , Retrospective StudiesABSTRACT
Chili pepper fruits of the genus Capsicum represent excellent experimental models to study the growth, development, and ripening processes in a non-climacteric species at the physiological, biochemical, and molecular levels. Fruit growth, development, and ripening involve a complex, harmonious, and finely controlled regulation of gene expression. The purpose of this study was to estimate the changes in transcriptome diversity and specialization, as well as gene specificities during fruit development in this crop, and to illustrate the advantages of estimating these parameters. To achieve these aims, we programmed and made publicly available an R package. In this study, we applied these methods to a set of 179 RNA-Seq libraries from a factorial experiment that includes 12 different genotypes at various stages of fruit development. We found that the diversity of the transcriptome decreases linearly from the flower to the mature fruit, while its specialization follows a complex and non-linear behavior during this process. Additionally, by defining sets of genes with different degrees of specialization and applying Gene Ontology enrichment analysis, we identified processes, functions, and components that play a central role in particular fruit development stages. In conclusion, the estimation of diversity, specialization, and specificity summarizes the global properties of the transcriptomes, providing insights that are difficult to achieve by other means.
ABSTRACT
BACKGROUND AND OBJECTIVE: Little information is available on how to assess the impact of research studies conducted in government hospitals in Latin America and specifically in Mexico. We aimed to determine the returns on investment of the research projects that were carried out in the Hospital General "Dr. Manuel Gea Gonzalez" (HGMGG), a general university hospital located in Mexico City, using a categorization model. METHODS: We conducted a study including bibliometric analyses of publications associated with all research studies performed during the period 2016-2019 in the HGMGG and investigator interviews, according to the payback framework categorization model. RESULTS: All studies analyzed had a positive impact based on outcomes in 5 "payback categories": (1) knowledge; (2) research targeting, capacity building, and absorption; (3) policy and product development; (4) health benefits; and (5) broader economic benefits. CONCLUSIONS: To date, it has not been possible to establish a set of indicators that show the results of the investigations carried out by medical specialists in training, who carry out the bulk of medical care in general hospitals and in the National Institutes of Health in Mexico. We identified, in the 5 categories of the payback framework model, different areas of opportunity to improve the benefits of the hospital's medical services through the development of scientific research projects.
Subject(s)
Bibliometrics , United States , Humans , Hospitals, UniversityABSTRACT
BACKGROUND: Survival rate (SR) is frequently used to compare drought tolerance among plant genotypes. While a variety of techniques for evaluating the stress status of plants under drought stress conditions have been developed, determining the critical point for the recovery irrigation to evaluate plant SR often relies directly on a qualitative inspection by the researcher or on the employment of complex and invasive techniques that invalidate the subsequent use of the tested individuals. RESULTS: Here, we present a simple, instantaneous, and non-invasive method to estimate the survival probability of Arabidopsis thaliana plants after severe drought treatments. The quantum yield (QY), or efficiency of photosystem II, was monitored in darkness (Fv/Fm) and light (Fv'/Fm') conditions in the last phase of the drought treatment before recovery irrigation. We found a high correlation between a plant's Fv'/Fm' value before recovery irrigation and its survival phenotype seven days after, allowing us to establish a threshold between alive and dead plants in a calibration stage. This correlation was maintained in the Arabidopsis accessions Col-0, Ler-0, C24, and Kondara under the same conditions. Fv'/Fm' was then applied as a survival predictor to compare the drought tolerance of transgenic lines overexpressing the transcription factors ATAF1 and PLATZ1 with the Col-0 control. CONCLUSIONS: The results obtained in this work demonstrate that the chlorophyll a fluorescence parameter Fv'/Fm' can be used as a survival predictor that gives a numerical estimate of the Arabidopsis drought SR before recovery irrigation. The procedure employed to get the Fv'/Fm' measurements is fast, non-destructive, and requires inexpensive and easy-to-handle equipment. Fv'/Fm' as a survival predictor can be used to offer an overview of the photosynthetic state of the tested plants and determine more accurately the best timing for rewatering to assess the SR, especially when the symptoms of severe dehydration between genotypes are not contrasting enough to identify a difference visually.
ABSTRACT
Background: The impact of strategies for rapid diagnostic screening of Candida auris on hospital operations has not been previously characterized. We describe the implementation of in-house polymerase chain reaction (PCR) testing on admission for screening of colonization with C. auris, associated process improvements, and financial impact. Methods: This study was conducted across an integrated health system. Patients were tested based on risk factors for C. auris carriage. Pre-intervention, the PCR was sent out to a reference laboratory, and postintervention was performed in-house. Changes in the incidence rates (IRs) of C. auris present on admission (CA-POA) and C. auris hospital-onset fungemia (CA-HOF) were assessed using interrupted time series analysis. The economic impact on isolation and testing costs was calculated. Results: Postintervention, the IR of CA-POA doubled (IRR, 2.57; 95% CI, 1.16-5.69; P = .02) compared with the pre-intervention period. The baseline rate of CA-HOF was increasing monthly by 14% (95% CI, 1.05-1.24; P = .002) pre-intervention, while during the postintervention period there was a change in slope with a monthly decrease in IR of 13% (95% CI, 0.80-0.99; P = .02). The median turnaround time (TAT) of the results (interquartile range) was reduced from 11 (8-14) days to 2 (1-3) days. Savings were estimated to be between $772 513.10 and $3 730 480.26. Conclusions: By performing in-house PCR for screening of C. auris colonization on admission, we found a doubling of CA-POA rates, a subsequent decrease in CA-HOF rates, reduced TAT for PCR results, and more efficient use of infection control measures. In-house testing was cost-effective in a setting of relatively high prevalence among individuals with known risk factors.
ABSTRACT
The presence and levels of transgenic maize in Mexico and the effect this could have on local landraces or closely related species such as teosinte has been the subject of several previous reports, some showing contrasting results. Cultural, social and political factors all affect maize cultivation in Mexico and although since 1998 there has been a moratorium on the commercial cultivation of transgenic maize, Mexico imports maize, mainly from the USA where transgenic cultivars are widely grown. Additionally extensive migration between rural areas in Mexico and the USA and customs of seed exchange between farmers may also play an unintentional role in the establishment of transgenic seed. A comprehensive study of all Mexican maize landraces throughout the country is not feasible, however this report presents data based on analysis of 3204 maize accessions obtained from the central region of Mexico (where permits have never been authorized for cultivation of transgenic maize) and the northern region (where for a short period authorization for experimental plots was granted). The results of the study confirm that transgenes are present in all the geographical areas sampled and were more common in germplasm obtained in the northern region. However, there was no evidence that regions where field trials had been authorized showed higher levels of transgene presence or that the morphology of seed lots harboring transgenic material was significantly modified in favor of expected transgenic phenotypes.
Subject(s)
Zea mays , Animals , Plants, Genetically Modified/genetics , Zea mays/genetics , Mexico , Transgenes , Animals, Genetically ModifiedABSTRACT
INTRODUCTION: Multidrug-resistant (MDR) Gram-negative organisms cause life-threatening infections, and the incidence is rising globally. Timely therapy for these infections has a direct impact on patient survival. This study aimed to determine the impact of a multidisciplinary diagnostic and antimicrobial stewardship (AMS) workflow on time to appropriate therapy (TAP) for these infections using novel beta-lactam/beta-lactamase inhibitors. METHODS: This was a retrospective quasi-experimental study of adult patients with carbapenem-resistant Enterobacterales (CRE) and multidrug-resistant Pseudomonas (MDR PsA) infections at a 1500 bed university hospital. Included patients who received ≥ 72 hours of ceftazidime-avibactam (CZA) or ceftolozane-tazobactam (C/T) from December 2017 to December 2019. During the pre-intervention period (December 2017 to December 2018), additional susceptibilities (including CZA and C/T) were performed only upon providers' request. In 2019, reflex algorithms were implemented for faster identification and testing of all CRE/MDR PsA isolates. Results were communicated in real-time to the AMS team to tailor therapy. RESULTS: A total of 99 patients were included, with no between-group differences at baseline. The median age was 60 years and 56 (56.7%) were in intensive care at the time of culture collection. Identified organisms included 71 (71.7%) MDR PsA and 26 CRE, of which 18 were carbapenemase producers (Klebsiella-producing carbapenemase = 12, New Delhi metallo-ß-lactamase = 4, Verona integron-encoded metallo-ß-lactamase = 2). The most common infections were pneumonia (49.5%) and bacteraemia (30.3%). A decrease was found in median TAP (103 [IQR 76.0-156.0] vs. 75 [IQR 56-100] hours; P < 0.001). Median time from culture collection to final susceptibility results was shorter in the post-intervention group (123 vs. 93 hours; P < 0.001). CONCLUSION: This study identified improvement in TAP in MDR PsA and CRE infections with implementation of a reflex microbiology workflow and multidisciplinary antimicrobial stewardship initiatives.
Subject(s)
Antimicrobial Stewardship , Arthritis, Psoriatic , Humans , Middle Aged , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology , Retrospective Studies , Workflow , Arthritis, Psoriatic/drug therapy , Ceftazidime/pharmacology , Gram-Negative Bacteria , beta-Lactamase Inhibitors/therapeutic use , beta-Lactamase Inhibitors/pharmacology , beta-Lactamases , Carbapenems/pharmacology , Drug Combinations , Azabicyclo Compounds/pharmacology , Microbial Sensitivity Tests , Pseudomonas aeruginosaABSTRACT
Gene co-expression networks are powerful tools to understand functional interactions between genes. However, large co-expression networks are difficult to interpret and do not guarantee that the relations found will be true for different genotypes. Statistically verified time expression profiles give information about significant changes in expressions through time, and genes with highly correlated time expression profiles, which are annotated in the same biological process, are likely to be functionally connected. A method to obtain robust networks of functionally related genes will be useful to understand the complexity of the transcriptome, leading to biologically relevant insights. We present an algorithm to construct gene functional networks for genes annotated in a given biological process or other aspects of interest. We assume that there are genome-wide time expression profiles for a set of representative genotypes of the species of interest. The method is based on the correlation of time expression profiles, bound by a set of thresholds that assure both, a given false discovery rate, and the discard of correlation outliers. The novelty of the method consists in that a gene expression relation must be repeatedly found in a given set of independent genotypes to be considered valid. This automatically discards relations particular to specific genotypes, assuring a network robustness, which can be set a priori. Additionally, we present an algorithm to find transcription factors candidates for regulating hub genes within a network. The algorithms are demonstrated with data from a large experiment studying gene expression during the development of the fruit in a diverse set of chili pepper genotypes. The algorithm is implemented and demonstrated in a new version of the publicly available R package "Salsa" (version 1.0).
ABSTRACT
During the ripening process, the pericarp of chili pepper (Capsicum spp.) fruits accumulates large amounts of carotenoids. Although the carotenoid biosynthesis pathway in the Capsicum genus has been widely studied from different perspectives, the transcriptional regulation of genes encoding carotenoid biosynthetic enzymes has not been elucidated in this fruit. We analyzed RNA-Seq transcriptomic data from the fruits of 12 accessions of Capsicum annuum during the growth, development, and ripening processes using the R package named Salsa. We performed coexpression analyses between the standardized expression of genes encoding carotenoid biosynthetic enzymes (target genes (TGs)) and the genes of all expressed transcription factors (TFs). Additionally, we analyzed the promoter region of each biosynthetic gene to identify putative binding sequences for each selected TF candidate. We selected 83 TFs as putative regulators of the carotenogenic structural genes. From them, putative binding sites in the promoters of the carotenoid-biosynthesis-related structural genes were found for only 54 TFs. These results could guide the search for transcription factors involved in the regulation of the carotenogenic pathway in chili pepper fruits and might facilitate the collection of corresponding experimental evidence to corroborate their participation in the regulation of this biosynthetic pathway in Capsicum spp.
Subject(s)
Capsicum , Capsicum/metabolism , Carotenoids/metabolism , Fruit/metabolism , Gene Expression Regulation, Plant , RNA-Seq , Transcription Factors/genetics , Transcription Factors/metabolism , Transfer Factor/genetics , Transfer Factor/metabolismABSTRACT
Background: Mycobacterium abscessus is increasingly recognized as a human pathogen causing life-threatening infections in immunocompromised patients. There is a paucity of data around this topic in solid organ transplant (SOT) recipients. Methods: This work was a single-center retrospective cohort study of all SOT recipients with a positive culture for M abscessus between 2013 and 2018. Results: A total of 20 patients (55% female) met inclusion criteria, including 1 kidney recipient (5.0%), 2 liver recipients (10.0%), 12 lung recipients (60.0%), 1 heart recipient (5.0%), and 4 combined organ recipients (20.0%). The median time from SOT to infection was 100 days (range, 30-431 days). Thirteen (65.0%) patients (1 kidney, 1 heart, 7 lung, 1 liver, 1 intestine, and 2 multivisceral) were treated with a median duration of 185 antibiotic days (range, 20-523 days). Among them, M abscessus was isolated from respiratory samples in 8 and nonrespiratory samples in 5; 4 of 13 (30.8%) patients had treatment failure and 3 of 13 (23.1%) had unrelated deaths within 1 year after diagnosis. Seven patients (5 lung transplant recipients) with the organism isolated from respiratory samples were not treated as their cultures represented airway colonization or contamination; of those, 2 (28.6%) died (unrelated to infection) and 5 (71.4%) were alive without the infection after 1 year of follow-up. Conclusions: Mycobacterium abscessus infections affect SOT recipients with a high proportion of clinical failures. However, in lung recipients, not all positive cultures correlated with infection, and without treatment some patients had good clinical outcomes. Thus, differentiating colonization from infection is important, and infection prevention measures and novel therapeutic agents are needed for SOT recipients.
ABSTRACT
Capsicum spp. members are a rich source of specialized compounds due to their secondary metabolism. Some metabolic pathways have suffered modifications during the domestication process and improvement of agricultural traits. Here, we compared non-targeted LC-MS profiles from several areas: wild accessions (C. annuum L. var. glabriusculum), domesticated cultivars (C. annuum L.), and the F1 progeny of a domesticated, and a wild accession cross (in both directions) throughout seven stages of fruit development of chili pepper fruits. The main detected differences were in glycerophospholipid metabolism, flavone and flavonol biosynthesis, sphingolipid metabolism, and cutin biosynthesis. The domesticated group exhibited a higher abundance in 12'-apo-ß-carotenal, among others capsorubin, and ß-tocopherol. Palmitic acid and derivates, terpenoids, and quercitrin were prevalent in the wild accessions. F1 progeny showed a higher abundance of capsaicin, glycol stearate, and soyacerebroside I. This work supports evidence of the side-affectation of trait selection over the metabolism of chili pepper fruit development. Furthermore, it was also observed that there was a possible heterosis effect over the secondary metabolism in the F1 progeny.
ABSTRACT
BACKGROUND: A large portion of prescribing errors can be attributed to deficiencies in medication knowledge. These errors are preventable and most often occur at the time of prescription. Antimicrobials are the drug class most common incorrectly prescribed. OBJECTIVE: To characterize the relationship between clinical competence and antibiotic prescription errors. We also investigated the frequency and severity of antibiotic prescription errors to identify items and attributes of clinical competence which are correlated with the antibiotic prescription error ratio. METHOD: A cross-sectional study was applied to assess clinical competence of junior medical residents in two reference academic hospitals and a regional hospital in Mexico City. It was conducted during February 2019. We used an infectious disease Objective Structured Clinical Examination (OSCE) to assess clinical competence and a measure of frequency, and severity of antibiotic prescription errors. RESULTS: The number of eligible participants was ~ 255 (hospital meeting attendance), and the number of residents in this study were 51 (~ 20%), 31 were female (60.8%). The mean OSCE score was 0.692 ± 0.073. The inter-item (Cronbach's alpha = 0.927) and inter-station internal consistency was adequate (Cronbach's alpha = 0.774). The G coefficient in generalizability theory analysis was 0.84. The antibiotic prescription error ratio was 45.1% ± 7%. The most frequent category of severity of antibiotic prescription errors was category E (errors that may contribute to or result in temporary harm to the patient and require intervention), 235 (65.2%). We observed a negative and significant correlation between clinical competence and antibiotic prescription errors (r = -0.33, p < 0.05, CI95% -0.57 to -0.07), which remained significant after controlling for the effect of gender and time since graduation from medical school (r = -0.39, p < 0.01, CI95% -0.625 to -0.118). Using exploratory factor analysis we identified two factors, which explained 69% of the variance in clinical competence, factor 1 evaluated socio-clinical skills and factor 2 evaluated diagnostic-therapeutic skills. Factor 2 was correlated with antibiotic prescription error ratio (r = -0.536, p < 0.001). CONCLUSIONS: We observed a negative correlation between clinical competence and antibiotic prescription error ratio in graduated physicians who have been accepted in a medical specialty. The therapeutic plan, which is a component of the clinical competence score, and the prescription skills had a negative correlation with antibiotic prescription errors. The most frequent errors in antibiotic prescriptions would require a second intervention.
Subject(s)
Clinical Competence , Internship and Residency , Anti-Bacterial Agents/therapeutic use , Cross-Sectional Studies , Drug Prescriptions , Female , Humans , MaleABSTRACT
BACKGROUND: Joint ultrasound examination using the HEAD-US method in the detection of early arthropathy is poorly studied in our country. OBJECTIVE: To compare the clinical and ultrasound evaluation of the joints in haemophilia. METHOD: Longitudinal, prospective and descriptive study with paediatric patients with haemophilia A and B evaluated with the HJHS 2.1 scale and ultrasound with a linear transducer of 8 to 12 MHz. Elbows, knees and ankles joints were evaluated bilaterally, with HEAD-US protocol. RESULTS: 69 paediatric patients were included of which 48 with severe haemophilia A (weight: 40.1 kg). On the HJHS scale, a greater involvement was observed in the left knee (0.49), and less in the right ankle (0.05). With the HEAD-US scale, the most affected was the right knee (0.78). There is a significant relationship in the involvement of the right knee evaluated with the HEAD-US scale in the presence of inhibitor. CONCLUSIONS: Weight above the 50th percentile is an independent risk factor for joint bleeding complications, while age and type of haemophilia do not appear to be related. The HEAD-US method is a useful and accessible tool for early detection of arthropathy and hemarthrosis.
ANTECEDENTES: La exploración articular por ultrasonido mediante el método HEAD-US en la detección de la artropatía temprana ha sido poco estudiada en nuestro país. OBJETIVO: Comparar la evaluación clínica y por ultrasonido de las articulaciones en niños con hemofilia. MÉTODOS: Estudio longitudinal, prospectivo y descriptivo con pacientes pediátricos con hemofilia A y B valorados con la escala HJHS 2.1 y ultrasonido con transductor lineal de 8 a 12 MHz. Se evaluaron las articulaciones de codos, rodillas y tobillos de forma bilateral, con el método HEAD-US. RESULTADOS: Se incluyeron 69 pacientes; de ellos, 48 con hemofilia A grave (peso: 40.1 kg). En la escala HJHS se observó mayor afectación en la rodilla izquierda (0.49) y menor en el tobillo derecho (0.05). Con la escala HEAD-US, la más afectada fue la rodilla derecha (0.78). Existe una relación significativa en la afectación de la rodilla derecha evaluada con la escala HEAD-US en presencia de inhibidor. CONCLUSIONES: El peso superior al percentil 50 es un factor de riesgo independiente de complicaciones por sangrado articular, mientras que la edad y el tipo de hemofilia no parecen relacionados. El método HEAD-US es una herramienta útil y accesible para la detección temprana de artropatía y hemartrosis.
Subject(s)
Elbow Joint , Hemophilia A , Child , Elbow Joint/diagnostic imaging , Hemarthrosis/diagnostic imaging , Hemarthrosis/etiology , Hemophilia A/complications , Hemophilia A/diagnostic imaging , Humans , Prospective Studies , Ultrasonography/methodsABSTRACT
BACKGROUND: Pseudomonas aeruginosa is a persistent and difficult-to-treat pathogen in many patients, especially those with Cystic Fibrosis (CF). Herein, we describe a longitudinal analysis of a series of multidrug resistant (MDR) P. aeruginosa isolates recovered in a 17-month period, from a young female CF patient who underwent double lung transplantation. Our goal was to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence evolution over time. METHODS: Twenty-two sequential P. aeruginosa isolates were obtained within a 17-month period, before and after a double-lung transplant. At the end of the study period, antimicrobial susceptibility testing, whole genome sequencing (WGS), phylogenetic analyses and RNAseq were performed in order to understand the genetic basis of the observed resistance phenotypes, establish the genomic population diversity, and define the nature of sequence changes over time. RESULTS: The majority of isolates were resistant to almost all tested antibiotics. A phylogenetic reconstruction revealed 3 major clades representing a genotypically and phenotypically heterogeneous population. The pattern of mutation accumulation and variation of gene expression suggested that a group of closely related strains was present in the patient prior to transplantation and continued to change throughout the course of treatment. A trend toward accumulation of mutations over time was observed. Different mutations in the DNA mismatch repair gene mutL consistent with a hypermutator phenotype were observed in two clades. RNAseq performed on 12 representative isolates revealed substantial differences in the expression of genes associated with antibiotic resistance and virulence traits. CONCLUSIONS: The overwhelming current practice in the clinical laboratories setting relies on obtaining a pure culture and reporting the antibiogram from a few isolated colonies to inform therapy decisions. Our analyses revealed significant underlying genomic heterogeneity and unpredictable evolutionary patterns that were independent of prior antibiotic treatment, highlighting the need for comprehensive sampling and population-level analysis when gathering microbiological data in the context of CF P. aeruginosa chronic infection. Our findings challenge the applicability of antimicrobial stewardship programs based on single-isolate resistance profiles for the selection of antibiotic regimens in chronic infections such as CF.
Subject(s)
Cystic Fibrosis , Pseudomonas Infections , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Cystic Fibrosis/complications , Cystic Fibrosis/drug therapy , Cystic Fibrosis/genetics , Drug Resistance, Multiple , Female , Humans , Microbial Sensitivity Tests , Phylogeny , Pseudomonas Infections/microbiology , Pseudomonas aeruginosaABSTRACT
BACKGROUND: Carbapenemase-producing, carbapenem-resistant Pseudomonas aeruginosa (CP-CRPA) is a global challenge. However, detection efforts can be laborious because numerous mechanisms produce carbapenem resistance. A minimum inhibitory concentration-based algorithm (imipenem- or meropenem-resistant plus ceftazidime-nonsusceptible plus cefepime-nonsusceptible) was proposed to identify the isolates most likely to harbor a carbapenemase; however, prospective validation in geographies displaying genotypic diversity and varied carbapenemase prevalence is warranted. METHODS: CRPA isolates were collected during the Enhancing Rational Antimicrobials for P. aeruginosa (ERACE-PA) global surveillance program from 17 sites in 12 countries. Isolates underwent susceptibility testing following local standards to ceftazidime, cefepime, and ceftolozane/tazobactam. Isolates underwent initial phenotypic carbapenemase screening followed by molecular testing if positive. The primary algorithm criteria were applied, and results were compared with phenotypic carbapenemase results to assess the performance of the algorithm. A secondary criterion, the algorithm criterion or imipenem- or meropenem-resistant plus ceftolozane/tazobactam-nonsusceptible, was assessed. RESULTS: A total of 807 CRPA were assessed, and 464 isolates met the algorithm criteria described above. Overall, testing was reduced by 43% compared with testing all CRPA. Carbapenemase-positive isolates missed by the algorithm were largely driven by Guiana extended spectrum (GES). Addition of the criterion of imipenem- or meropenem-resistant plus ceftolozane/tazobactam-nonsusceptible decreased the number of CP-CRPA missed by the algorithm (21 vs 40 isolates, respectively), reducing number of isolates tested by 39%. CONCLUSIONS: Application of the initial algorithm (imipenem- or meropenem-resistant plus ceftazidime-nonsusceptible plus cefepime-nonsusceptible) performed well in a global cohort, with 33% phenotypically carbapenemase-positive isolates. The addition of imipenem- or meropenem-resistant plus ceftolozane/tazobactam-nonsusceptible reduced the number of phenotypically carbapenemase-positive isolates missed and may be useful in areas with a prominence of GES.
ABSTRACT
Resumen Antecedentes: La exploración articular por ultrasonido mediante el método HEAD-US en la detección de la artropatía temprana ha sido poco estudiada en nuestro país. Objetivo: Comparar la evaluación clínica y por ultrasonido de las articulaciones en niños con hemofilia. Métodos: Estudio longitudinal, prospectivo y descriptivo con pacientes pediátricos con hemofilia A y B valorados con la escala HJHS 2.1 y ultrasonido con transductor lineal de 8 a 12 MHz. Se evaluaron las articulaciones de codos, rodillas y tobillos de forma bilateral, con el método HEAD-US. Resultados: Se incluyeron 69 pacientes; de ellos, 48 con hemofilia A grave (peso: 40.1 kg). En la escala HJHS se observó mayor afectación en la rodilla izquierda (0.49) y menor en el tobillo derecho (0.05). Con la escala HEAD-US, la más afectada fue la rodilla derecha (0.78). Existe una relación significativa en la afectación de la rodilla derecha evaluada con la escala HEAD-US en presencia de inhibidor. Conclusiones: El peso superior al percentil 50 es un factor de riesgo independiente de complicaciones por sangrado articular, mientras que la edad y el tipo de hemofilia no parecen relacionados. El método HEAD-US es una herramienta útil y accesible para la detección temprana de artropatía y hemartrosis.
Abstract Background: Joint ultrasound examination using the HEAD-US method in the detection of early arthropathy is poorly studied in our country. Objective: To compare the clinical and ultrasound evaluation of the joints in haemophilia. Methods: Longitudinal, prospective and descriptive study with paediatric patients with haemophilia A and B evaluated with the HJHS 2.1 scale and ultrasound with a linear transducer of 8 to 12 MHz. Elbows, knees and ankles joints were evaluated bilaterally, with HEAD-US protocol. Results: 69 paediatric patients were included of which 48 with severe haemophilia A (weight: 40.1 kg). On the HJHS scale, a greater involvement was observed in the left knee (0.49), and less in the right ankle (0.05). With the HEAD-US scale, the most affected was the right knee (0.78). There is a significant relationship in the involvement of the right knee evaluated with the HEAD-US scale in the presence of inhibitor. Conclusions: Weight above the 50th percentile is an independent risk factor for joint bleeding complications, while age and type of haemophilia do not appear to be related. The HEAD-US method is a useful and accessible tool for early detection of arthropathy and hemarthrosis.
ABSTRACT
Gene expression is the primary molecular phenotype and can be estimated in specific organs or tissues at particular times. Here we analyzed genome-wide inheritance of gene expression in fruits of chili pepper (Capsicum annuum L.) in reciprocal crosses between a domesticated and a wild accession, estimating this parameter during fruit development. We defined a general hierarchical schema to classify gene expression inheritance which can be employed for any quantitative trait. We found that inheritance of gene expression is affected by both, the time of fruit development as well as the direction of the cross, and propose that such variations could be common in many developmental processes. We conclude that classification of inheritance patterns is important to have a better understanding of the mechanisms underlying gene expression regulation, and demonstrate that sets of genes with specific inheritance pattern at particular times of fruit development are enriched in different biological processes, molecular functions and cell components. All curated data and functions for analysis and visualization are publicly available as an R package.
Subject(s)
Capsicum/genetics , Fruit/genetics , Gene Expression Regulation, Plant , Computational Biology , Crosses, Genetic , Databases, Genetic , Gene Expression , Gene Expression Profiling , Genes, Plant , Genetic Techniques , Genotype , Models, Statistical , Programming Languages , SoftwareABSTRACT
The most studied DNA methylation pathway in plants is the RNA Directed DNA Methylation (RdDM), a conserved mechanism that involves the role of noncoding RNAs to control the expansion of the noncoding genome. Genome-wide DNA methylation levels have been reported to correlate with genome size. However, little is known about the catalog of noncoding RNAs and the impact on DNA methylation in small plant genomes with reduced noncoding regions. Because of the small length of intergenic regions in the compact genome of the carnivorous plant Utricularia gibba, we investigated its repertoire of noncoding RNA and DNA methylation landscape. Here, we report that, compared to other angiosperms, U. gibba has an unusual distribution of small RNAs and reduced global DNA methylation levels. DNA methylation was determined using a novel strategy based on long-read DNA sequencing with the Pacific Bioscience platform and confirmed by whole-genome bisulfite sequencing. Moreover, some key genes involved in the RdDM pathway may not represented by compensatory paralogs or comprise truncated proteins, for example, U. gibba DICER-LIKE 3 (DCL3), encoding a DICER endonuclease that produces 24-nt small-interfering RNAs, has lost key domains required for complete function. Our results unveil that a truncated DCL3 correlates with a decreased proportion of 24-nt small-interfering RNAs, low DNA methylation levels, and developmental abnormalities during female gametogenesis in U. gibba. Alterations in female gametogenesis are reminiscent of RdDM mutant phenotypes in Arabidopsis thaliana. It would be interesting to further study the biological implications of the DCL3 truncation in U. gibba, as it could represent an initial step in the evolution of RdDM pathway in compact genomes.
Subject(s)
DNA Methylation , Endonucleases/genetics , Endonucleases/metabolism , Gametogenesis , Lamiales/physiology , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism , Arabidopsis/physiology , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Gene Expression Regulation, Plant , Genome, Plant , Mutation , Plant Proteins/genetics , Plant Proteins/metabolism , RNA, Plant , RNA, Untranslated/metabolism , Ribonuclease III/genetics , Ribonuclease III/metabolismABSTRACT
The present study evaluated the in vitro potency of ceftazidime and cefepime among carbapenem-resistant Pseudomonas aeruginosa isolates collected as part of a global surveillance program and assessed the pharmacodynamic implications using previously published population pharmacokinetics. When susceptible, MICs resulted at the high end of distribution for both ceftazidime and cefepime, thus 6 g/day was required to achieve optimal pharmacodynamic profiles. These findings should be considered in the clinic and for the application of CLSI susceptibility breakpoints.