Penetration of a spinning sphere impacting a granular medium.

We investigate experimentally the influence of rotation on the penetration depth of a spherical projectile impacting a granular medium. We show that a rotational motion significantly increases the penetration depth achieved. Moreover, we model our experimental results by modifying the frictional term of the equation describing the penetration dynamics of an object in a granular medium. In particular, we find that the frictional drag decreases linearly with the velocity ratio between rotational (spin motion) and translational (falling motion) velocities. The good agreement between our model and our experimental measurements offers perspectives for estimating the depth that spinning projectiles reach after impacting onto a granular ground, such as happens with seeds dropped from aircraft or with landing probes.

Latin-American guidelines of recommendations at discharge from an acute coronary syndrome.

The diagnostic criteria, treatments at the time of admission, and drugs used in patients with acute coronary syndrome are well defined in countless guidelines. However, there is uncertainty about the measures to recommend during patient discharge planning. This document brings together the most recent evidence and the standardized and optimal treatment for patients at the time of discharge from hospitalization for an acute coronary syndrome, for comprehensive and safe care in the patient's transition between care from the acute event to the outpatient care, with the aim of optimizing the recovery of viable myocardium, guaranteeing the most appropriate secondary prevention, reducing the risk of a new coronary event and mortality, as well as the adequate reintegration of patients into daily life.

Los criterios diagnósticos, los tratamientos en el momento de la admisión y los fármacos utilizados en pacientes con síndrome coronario agudo están bien definidos en innumerables guías. Sin embargo, existe incertidumbre acerca de las medidas para recomendar durante la planificación del egreso de los pacientes. Este documento reúne las evidencias más recientes y el tratamiento estandarizado y óptimo para los pacientes al momento del egreso de una hospitalización por un síndrome coronario agudo, para un cuidado integral y seguro en la transición del paciente entre la atención del evento agudo y el cuidado ambulatorio, con el objetivo de optimizar la recuperación de miocardio viable, garantizar la prevención secundaria más adecuada, reducir el riesgo de un nuevo evento coronario y la mortalidad, así como la adecuada reinserción de los pacientes en la vida cotidiana.

Role of UDP-Glycosyltransferase (ugt) Genes in Detoxification and Glycosylation of 1-Hydroxyphenazine (1-HP) in Caenorhabditis elegans.

Caenorhabditis elegans is a useful model organism to study the xenobiotic detoxification pathways of various natural and synthetic toxins, but the mechanisms of phase II detoxification are understudied. 1-Hydroxyphenazine (1-HP), a toxin produced by the bacterium Pseudomonas aeruginosa, kills C. elegans. We previously showed that C. elegans detoxifies 1-HP by adding one, two, or three glucose molecules in N2 worms. Our current study evaluates the roles that some UDP-glycosyltransferase (ugt) genes play in 1-HP detoxification. We show that ugt-23 and ugt-49 knockout mutants are more sensitive to 1-HP than reference strains N2 or PD1074. Our data also show that ugt-23 knockout mutants produce reduced amounts of the trisaccharide sugars, while the ugt-49 knockout mutants produce reduced amounts of all 1-HP derivatives except for the glucopyranosyl product compared to the reference strains. We characterized the structure of the trisaccharide sugar phenazines made by C. elegans and showed that one of the sugar modifications contains an N-acetylglucosamine (GlcNAc) in place of glucose. This implies broad specificity regarding UGT function and the role of genes other than ogt-1 in adding GlcNAc, at least in small-molecule detoxification.

Persistent Radiculopathy Subsequent to Selective Nerve Root Block.

Transforaminal selective nerve root blocks are commonly performed for low back pain but are not without risk. This case report describes a 55-year-old man who underwent transforaminal selective nerve root block at the left lumbar (L) 4, L5, and sacral (S) 1 levels for radiating low back pain in the setting of moderate narrowing of the left L4-L5 foramen with impingement on the exiting left L4 nerve roots seen on magnetic resonance imaging (MRI). He developed left foot drop immediately after the procedure and presented to the acupuncture clinic two weeks later with persistent pain, left foot drop, and paresthesia of the left lateral shin. A repeat MRI of the lumbar spine showed mild enhancement of the left cauda equina, including the L5 and possibly L4 nerve roots. The large volume of injection into an area with neuroforaminal narrowing as well as the cytotoxicity of the contrast and anesthetic agents may have contributed to axon damage and left foot drop.

Subacute Combined Degeneration Masking Spinal Stenosis: A Case Report.

Subacute combined degeneration (SCD) from vitamin B12 deficiency and spinal stenosis from degenerative changes may present similarly with weakness, sensory disturbances, and ataxia but require different treatments. This case report describes a 74-year-old male with suspected SCD who was discharged to an inpatient rehabilitation facility (IRF), did not improve with B12 supplementation, and later developed signs of myelopathy and diffuse joint pain. He ultimately was found to have severe cervical stenosis and pseudogout that were treated with a laminectomy and colchicine, respectively. Following surgical intervention, he returned to the IRF, where he had considerable functional improvement and was safely discharged home. This report shows the importance of recognizing the two conditions, their overlap, and the contrast between Occam's razor and Hickam's dictum.

Microflow liquid chromatography - multi-emitter nanoelectrospray mass spectrometry of oligonucleotides.

While the most sensitive LC-MS methods for oligonucleotide analysis contain ion-pairs in the mobile phase, these modifiers have been associated with instrument contamination and ion suppression. Typically, entire LC-MS systems are reserved for oligonucleotide LC-MS when using ion-pairing buffers. To overcome these limitations, numerous HILIC methods, liberated from ion-pairs, have been recently developed. Since ion-pairs play a role in analyte desorption from ESI droplets, their removal from mobile phases tend to impact method sensitivity. An effective way to recover MS sensitivity is to reduce the LC flow rate and therefore reduce ESI droplet size. With a focus on MS sensitivity, this study investigates the applicability of a microflow LC- nanoelectrospray MS platform in oligonucleotide ion-pair RP and HILIC LC-MS methods. The platform is effective and substantially increased the MS sensitivity of HILIC methods. Furthermore, LC method development for both types of separations provide insight into microflow chromatography of oligonucleotides, an under investigated chromatographic scale.

Unknown Metabolite Identification Using Machine Learning Collision Cross-Section Prediction and Tandem Mass Spectrometry.

Ion mobility (IM) spectrometry provides semiorthogonal data to mass spectrometry (MS), showing promise for identifying unknown metabolites in complex non-targeted metabolomics data sets. While current literature has showcased IM-MS for identifying unknowns under near ideal circumstances, less work has been conducted to evaluate the performance of this approach in metabolomics studies involving highly complex samples with difficult matrices. Here, we present a workflow incorporating de novo molecular formula annotation and MS/MS structure elucidation using SIRIUS 4 with experimental IM collision cross-section (CCS) measurements and machine learning CCS predictions to identify differential unknown metabolites in mutant strains of Caenorhabditis elegans. For many of those ion features, this workflow enabled the successful filtering of candidate structures generated by in silico MS/MS predictions, though in some cases, annotations were challenged by significant hurdles in instrumentation performance and data analysis. While for 37% of differential features we were able to successfully collect both MS/MS and CCS data, fewer than half of these features benefited from a reduction in the number of possible candidate structures using CCS filtering due to poor matching of the machine learning training sets, limited accuracy of experimental and predicted CCS values, and lack of candidate structures resulting from the MS/MS data. When using a CCS error cutoff of ±3%, on average, 28% of candidate structures could be successfully filtered. Herein, we identify and describe the bottlenecks and limitations associated with the identification of unknowns in non-targeted metabolomics using IM-MS to focus and provide insights into areas requiring further improvement.

An anchored experimental design and meta-analysis approach to address batch effects in large-scale metabolomics.

Untargeted metabolomics studies are unbiased but identifying the same feature across studies is complicated by environmental variation, batch effects, and instrument variability. Ideally, several studies that assay the same set of metabolic features would be used to select recurring features to pursue for identification. Here, we developed an anchored experimental design. This generalizable approach enabled us to integrate three genetic studies consisting of 14 test strains of Caenorhabditis elegans prior to the compound identification process. An anchor strain, PD1074, was included in every sample collection, resulting in a large set of biological replicates of a genetically identical strain that anchored each study. This enables us to estimate treatment effects within each batch and apply straightforward meta-analytic approaches to combine treatment effects across batches without the need for estimation of batch effects and complex normalization strategies. We collected 104 test samples for three genetic studies across six batches to produce five analytical datasets from two complementary technologies commonly used in untargeted metabolomics. Here, we use the model system C. elegans to demonstrate that an augmented design combined with experimental blocks and other metabolomic QC approaches can be used to anchor studies and enable comparisons of stable spectral features across time without the need for compound identification. This approach is generalizable to systems where the same genotype can be assayed in multiple environments and provides biologically relevant features for downstream compound identification efforts. All methods are included in the newest release of the publicly available SECIMTools based on the open-source Galaxy platform.

The Re-Identification of Previously Unidentifiable Clinical Non-Tuberculous Mycobacterial Isolates Shows Great Species Diversity and the Presence of Other Acid-Fast Genera.

Non-tuberculous mycobacteria that cannot be identified at the species level represent a challenge for clinical laboratories, as proper species assignment is key to implementing successful treatments or epidemiological studies. We re-identified forty-eight isolates of Ziehl-Neelsen (ZN)-staining-positive "acid-fast bacilli" (AFB), which were isolated in a clinical laboratory and previously identified as Mycobacterium species but were unidentifiable at the species level with the hsp65 PCR restriction fragment length polymorphism analysis (PRA). As most isolates also could not be identified confidently via 16S, hsp65, or rpoB DNA sequencing and a nBLAST search analysis, we employed a phylogenetic method for their identification using the sequences of the 16S rDNA, which resulted in the identification of most AFB and a Mycobacterium species diversity not found before in our laboratory. Most were rare species with only a few clinical reports. Moreover, although selected with the ZN staining as AFB, not all isolates belonged to the genus Mycobacterium, and we report for the first time in Latin America the isolation of Nocardia puris, Tsukamurella pulmosis, and Gordonia sputi from sputum samples of symptomatic patients. We conclude that ZN staining does not differentiate between the genus Mycobacterium and other genera of AFB. Moreover, there is a need for a simple and more accurate tree-based identification method for mycobacterial species. For this purpose, and in development in our lab, is a web-based identification system using a phylogenetic analysis (including all AFB genera) based on 16S rDNA sequences (and in the future multigene datasets) and the closest relatives.

Ventilación mecánica invasiva en COVID-19, ¿una estrategia mortal? / Invasive mechanical ventilation in COVID-19, a deadly strategy? / Ventilação mecânica invasiva no COVID-19, uma estratégia mortal?

Resumen Desde la epidemia de poliomielitis de Copenhague en 1952, los cuidados intensivos no habían enfrentado un desafío tan importante desde el punto de vista médico y mediático como la pandemia por COVID-19, la cual ha tenido consecuencias devastadoras; una de ellas es el desborde en la capacidad de las Unidades de Cuidados Intensivos y, como resultado, la posibilidad de ofrecer ventilación mecánica ha sido insuficiente; además, las características avasallantes y rápidamente cambiantes de la información médica y no médica, al igual que la mortalidad relacionada a la enfermedad, han desarrollado una narrativa deletérea al tratamiento de estos pacientes con apoyo ventilatorio invasivo, lo que ha hecho resurgir viejas cuestiones sobre ésta como lesiones inducidas por ventilación mecánica invasiva. Todo esto ha promovido la revivificación del apoyo ventilatorio no invasivo como medida salvadora; sin embargo, como veremos en esta aproximación a la luz de la evidencia, es errónea y puede resultar deletérea no sólo para el paciente, sino también para el personal de salud que cuida de éstos.

Abstract Since the Copenhagen polio epidemic in 1952, intensive care has not faced as important a challenge from a medical and media point of view as the COVID-19 pandemic, which has had devastating consequences, one of which is the overflow in the capacity of Intensive Care Units, and as a result of the capacity to offer mechanical ventilation has been insufficient, in addition to the overwhelming and rapidly changing characteristics of medical and non-medical information, also of disease-related mortality, has developed a deleterious narrative to the treatment of these patients with invasive ventilatory support and raising old questions about this as injuries induced by invasive mechanical ventilation. All this has promoted the rise of non-invasive ventilatory support as a saving lifes strategy, however, as we will see, this approach, in scope of the evidence, is erroneous and can be hazardous not only for the patient but also for health personnel who care for them.

Resumo Desde a epidemia de poliomielite em Copenhague em 1952, a terapia intensiva não enfrenta um desafio tão importante do ponto de vista médico e midiático como a pandemia de COVID-19, que teve consequências devastadoras, sendo uma delas o transbordamento da capacidade de terapia intensiva unidades, e com isso a possibilidade de oferta de ventilação mecânica tem sido insuficiente, além das características avassaladoras e em rápida mudança das informações médicas e não médicas, bem como a mortalidade relacionada à doença, desenvolveu uma narrativa deletéria ao tratamento da esses pacientes com suporte ventilatório invasivo e ressurgiu antigas questões sobre o mesmo, como as lesões induzidas pela ventilação mecânica invasiva. Tudo isso tem promovido o renascimento do suporte ventilatório não invasivo como medida de economia, porém, como veremos, essa abordagem, à luz das evidências, é errônea e pode ser deletéria não só para o paciente, mas também para o pessoal de saúde quem cuida deles.

The specificity of the malarial VAR2CSA protein for chondroitin sulfate depends on 4-O-sulfation and ligand accessibility.

Placental malaria infection is mediated by the binding of the malarial VAR2CSA protein to the placental glycosaminoglycan, chondroitin sulfate. Recombinant subfragments of VAR2CSA (rVAR2) have also been shown to bind specifically and with high affinity to cancer cells and tissues, suggesting the presence of a shared type of oncofetal chondroitin sulfate (ofCS) in the placenta and in tumors. However, the exact structure of ofCS and what determines the selective tropism of VAR2CSA remains poorly understood. In this study, ofCS was purified by affinity chromatography using rVAR2 and subjected to detailed structural analysis. We found high levels of N-acetylgalactosamine 4-O-sulfation (∼80-85%) in placenta- and tumor-derived ofCS. This level of 4-O-sulfation was also found in other tissues that do not support parasite sequestration, suggesting that VAR2CSA tropism is not exclusively determined by placenta- and tumor-specific sulfation. Here, we show that both placenta and tumors contain significantly more chondroitin sulfate moieties of higher molecular weight than other tissues. In line with this, CHPF and CHPF2, which encode proteins required for chondroitin polymerization, are significantly upregulated in most cancer types. CRISPR/Cas9 targeting of CHPF and CHPF2 in tumor cells reduced the average molecular weight of cell-surface chondroitin sulfate and resulted in a marked reduction of rVAR2 binding. Finally, utilizing a cell-based glycocalyx model, we showed that rVAR2 binding correlates with the length of the chondroitin sulfate chains in the cellular glycocalyx. These data demonstrate that the total amount and cellular accessibility of chondroitin sulfate chains impact rVAR2 binding and thus malaria infection.

Inpatient Rehabilitation Outcomes After Severe COVID-19 Infections: A Retrospective Cohort Study.

OBJECTIVE: The aim of the study was to describe the characteristics and functional outcomes of patients undergoing acute inpatient rehabilitation after hospitalization for COVID-19. DESIGN: Using a retrospective chart review, patients were identified who were admitted to inpatient rehabilitation after COVID-19. Patient information collected included sociodemographic characteristics, comorbidities, length of stay, discharge disposition, self-care, mobility, and cognitive functioning. These patients were compared with patients (controls) without COVID-19 with similar impairment codes treated at the same facility before the COVID-19 pandemic. RESULTS: There were 43 patients who were admitted to the inpatient rehabilitation hospital after COVID-19 infection and 247 controls. Patients who had COVID-19 were significantly more likely to be African American and to have been admitted to a long-term acute care hospital. They also had a longer length of rehabilitation stay. The groups did not differ by age, sex, or insurance. Functionally, although presenting with significantly worse mobility, self-care, and motor scores, the patients previously infected with COVID-19 had similar functional outcomes at time of discharge to the control group. CONCLUSIONS: Although patients with a history of COVID-19 had worse function at time of admission to acute rehabilitation, inpatient rehabilitation significantly improved their function to comparable levels as patients who did not have COVID-19. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME. CME OBJECTIVES: Upon completion of this article, the reader should be able to: (1) Identify how characteristics of patients with COVID-19 admitted to acute rehabilitation differ from those with similar admission codes but without COVID-19; (2) Describe changes in functional measures at admission and discharge of COVID-19 patients compared with patients without COVID-19; and (3) Recognize how inpatient rehabilitation may help reduce inequities in outcomes after severe COVID-19 infection. LEVEL: Advanced. ACCREDITATION: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 1.0 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

Comparison of High-Resolution Fourier Transform Mass Spectrometry Platforms for Putative Metabolite Annotation.

Fourier transform ion cyclotron resonance (FT-ICR) and Orbitrap mass spectrometry (MS) are among the highest-performing analytical platforms used in metabolomics. Non-targeted metabolomics experiments, however, yield extremely complex datasets that make metabolite annotation very challenging and sometimes impossible. The high-resolution accurate mass measurements of the leading MS platforms greatly facilitate this process by reducing mass errors and spectral overlaps. When high resolution is combined with relative isotopic abundance (RIA) measurements, heuristic rules, and constraints during searches, the number of candidate elemental formula(s) can be significantly reduced. Here, we evaluate the performance of Orbitrap ID-X and 12T solariX FT-ICR mass spectrometers in terms of mass accuracy and RIA measurements and how these factors affect the assignment of the correct elemental formulas in the metabolite annotation pipeline. Quality of the mass measurements was evaluated under various experimental conditions (resolution: 120, 240, 500 K; automatic gain control: 5 × 104, 1 × 105, 5 × 105) for the Orbitrap MS platform. High average mass accuracy (<1 ppm for UPLC-Orbitrap MS and <0.2 ppm for direct infusion FT-ICR MS) was achieved and allowed the assignment of correct elemental formulas for over 90% (m/z 75-466) of the 104 investigated metabolites. 13C1 and 18O1 RIA measurements further improved annotation certainty by reducing the number of candidates. Overall, our study provides a systematic evaluation for two leading Fourier transform (FT)-based MS platforms utilized in metabolite annotation and provides the basis for applying these, individually or in combination, to metabolomics studies of biological systems.

A Pilot Study of Microbial Succession in Human Rib Skeletal Remains during Terrestrial Decomposition.

The bones of decomposing vertebrates are colonized by a succession of diverse microbial communities. If this succession is similar across individuals, microbes may provide clues about the postmortem interval (PMI) during forensic investigations in which human skeletal remains are discovered. Here, we characterize the human bone microbial decomposer community to determine whether microbial succession is a marker for PMI. Six human donor subjects were placed outdoors to decompose on the soil surface at the Southeast Texas Applied Forensic Science facility. To also assess the effect of seasons, three decedents were placed each in the spring and summer. Once ribs were exposed through natural decomposition, a rib was collected from each body for eight time points at 3 weeks apart. We discovered a core bone decomposer microbiome dominated by taxa in the phylum Proteobacteria and evidence that these bone-invading microbes are likely sourced from the surrounding decomposition environment, including skin of the cadaver and soils. Additionally, we found significant overall differences in bone microbial community composition between seasons. Finally, we used the microbial community data to develop random forest models that predict PMI with an accuracy of approximately ±34 days over a 1- to 9-month time frame of decomposition. Typically, anthropologists provide PMI estimates based on qualitative information, giving PMI errors ranging from several months to years. Previous work has focused on only the characterization of the bone microbiome decomposer community, and this is the first known data-driven, quantitative PMI estimate of terrestrially decomposed human skeletal remains using microbial abundance information. IMPORTANCE Microbes are known to facilitate vertebrate decomposition, and they can do so in a repeatable, predictable manner. The succession of microbes in the skin and associated soil can be used to predict time since death during the first few weeks of decomposition. However, when remains are discovered after months or years, often the only evidence are skeletal remains. To determine if microbial succession in bone would be useful for estimating time since death after several months, human subjects were placed to decompose in the spring and summer seasons. Ribs were collected after 1 to 9 months of decomposition, and the bone microbial communities were characterized. Analysis revealed a core bone decomposer microbial community with some differences in microbial assembly occurring between seasons. These data provided time since death estimates of approximately ±34 days over 9 months. This may provide forensic investigators with a tool for estimating time since death of skeletal remains, for which there are few current methods.

Investigation of the Experimental Parameters of Ultraviolet Photodissociation for the Structural Characterization of Chondroitin Sulfate Glycosaminoglycan Isomers.

Glycosaminoglycans (GAGs) are linear polysaccharides that participate in a broad range of biological functions. Their incomplete biosynthesis pathway leads to nonuniform chains and complex mixtures. For this reason, the characterization of GAGs has been a difficult hurdle for the analytical community. Recently, ultraviolet photodissociation (UVPD) has emerged as a useful tool for determining sites of modification within a GAG chain. Here, we investigate the ability for UVPD to distinguish chondroitin sulfate epimers and the effects of UVPD experimental parameters on fragmentation efficiency. Chondroitin sulfate A (CS-A) and chondroitin sulfate B (CS-B), commonly referred to as dermatan sulfate (DS), differ only in C-5 uronic acid stereochemistry. This uronic acid difference can influence GAG-protein binding and therefore can alter the specific biological function of a GAG chain. Prior tandem mass spectrometry methods investigated for the elucidation of GAG structures also have difficulty differentiating 4-O from 6-O sulfation in chondroitin sulfate GAGs. Preliminary data using UVPD to characterize GAGs showed a promising ability to characterize 4-O sulfation in CS-A GAGs. Here, we look in depth at the capability of UVPD to distinguish chondroitin sulfate C-5 diastereomers and the role of key experimental parameters in making this distinction. Results using a 193 nm excimer laser and a 213 nm solid-state laser are compared for this study. The effect of precursor ionization state, the number of laser pulses (193 or 213 nm UVPD), and the use of the low-pressure versus high-pressure trap are investigated.

Severe Gastrointestinal Bleed Caused by a Rectal Dieulafoy Lesion.

Dieulafoy lesions are vessels that erode the overlying epithelium without the presence of an ulcer. When these lesions bleed, they can frequently be self-limited, but bleeding can be recurrent and prolonged. Although most commonly found in the lesser curvature of the proximal stomach, there are reports of these lesions in other gastrointestinal tract regions. This case identifies a Dieulafoy lesion found in the rectum, which was the source of this patient's profuse rectal bleeding.

Biochemical basis of differential selenium tolerance in arugula (Eruca sativa Mill.) and lettuce (Lactuca sativa L.).

Selenium (Se) biofortification in crops provides a valuable strategy to enhance human Se intake. However, crops vary greatly with their capacity in tolerating and metabolizing/accumulating Se, and the basis underlying such variations remains to be fully understood. Here, we compared the effects of Se and its analog S treatments on plant growth and biochemical responses between a Se accumulator (arugula) and a non-accumulator (lettuce). Arugula exhibited an increased biomass production in comparison with untreated controls at a higher selenate concentration than lettuce (20 µM vs. 10 µM Na2SeO4), showing better tolerance to Se. Arugula accumulated 3-folds more Se and S than lettuce plants under the same treatments. However, the Se/S assimilation as assessed by ATP sulfurylase and O-acetylserine (thiol)lyase activities was comparable between arugula and lettuce plants. Approximately 4-fold higher levels of Se in proteins under the same doses of Se treatments were observed in arugula than in lettuce, indicating that Se accumulators have better tolerance to selenoamino acids in proteins. Noticeably, arugula showed 6-fold higher ascorbate peroxidase activity and produced over 5-fold more glutathione and non-protein thiols than lettuce plants, which suggest critical roles of antioxidants in Se tolerance. Taken together, our results show that the elevated Se tolerance of arugula compared to lettuce is most likely due to an efficient antioxidant defense system. This study provides further insights into our understanding of the difference in tolerating and metabolizing/accumulating Se between Se accumulators and non-accumulators.

A rare case of spinal tuberculosis due to Mycobacterium bovis. Is zoonotic tuberculosis underdiagnosed?

We report a rare presentation of Pott's disease caused by M. bovis, suggesting transmission from infected cattle, and only the second case described so far in scientific reports. Noteworthy of this case was that the strain was only isolated on Stonebrink medium, a sodium pyruvate-containing culture medium for the isolation of mycobacteria. This medium is frequently ignored in diagnostic laboratories and in the laboratory manuals of most international health organizations. In general laboratories use a culture medium that contains glycerol, a carbon substrate considered inhibitory for the growth of M. bovis. The use of glycerol-containing medium therefore likely contributes towards underestimating zoonotic tuberculosis. Our case suggests that, in order to improved surveillance efforts for zoonotic TB and increase the notification rate for M. bovis to human TB, the use of pyruvate-containing media should be promoted, particularly in developing countries with a high prevalence of bovine TB, but also through the World Health Organization' (WHO) End TB Strategy and the Roadmap for Zoonotic TB.

Case-Case Comparison of Candida auris Versus Other Candida Species Bloodstream Infections: Results of an Outbreak Investigation in Colombia.

BACKGROUND: Candida auris is an emerging multidrug-resistant yeast that causes outbreaks in healthcare settings around the world. In 2016, clinicians and public health officials identified patients with C. auris bloodstream infections (BSI) in Colombian healthcare facilities. To evaluate potential risk factors and outcomes for these infections, we investigated epidemiologic and clinical features of patients with C. auris and other Candida species BSI. METHODS: We performed a retrospective case-case investigation in four Colombian acute care hospitals, defining a case as Candida spp. isolated from blood culture during January 2015-September 2016. C. auris BSI cases were compared to other Candida species BSI cases. Odds ratio (OR), estimated using logistic regression, was used to assess the association between risk factors and outcomes. RESULTS: We analyzed 90 patients with BSI, including 40 with C. auris and 50 with other Candida species. All had been admitted to the intensive care unit (ICU). No significant demographic differences existed between the two groups. The following variables were independently associated with C. auris BSI: ≥ 15 days of pre-infection ICU stay (OR: 5.62, CI: 2.04-15.5), evidence of severe sepsis (OR: 3.70, CI 1.19-11.48), and diabetes mellitus (OR 5.69, CI 1.01-31.9). CONCLUSION: Patients with C. auris BSI had longer lengths of ICU stay than those with other candidemias, suggesting that infections are acquired during hospitalization. This is different from other Candida infections, which are usually thought to result from autoinfection with host flora.

Genomic epidemiology of SARS-CoV-2 in Colombia

Coronavirus disease 2019 (COVID-19) was first diagnosed in Colombia from a traveler arriving from Italy on February 26, 2020. To date, available data on the origins and number or introductions of SARS-CoV-2 into the country are limited. Here, we sequenced SARS-CoV-2 from 43 clinical samples and--together with other 73 genomes sequences available from the country--we investigated the emergence and the routes of importation of COVID-19 into Colombia using epidemiological, historical air travel and phylogenetic observations. Our study provided evidence of multiple introductions, mostly from Europe, with at least 12 lineages being documented. Phylogenetic findings validated the lineage diversity, supported multiple importation events and the evolutionary relationship of epidemiologically-linked transmission chains. Our results reconstruct the early evolutionary history of SARS-CoV-2 in Colombia and highlight the advantages of genome sequencing to complement COVID-19 outbreak investigation.