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1.
N Engl J Med ; 385(6): 503-515, 2021 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-34170647

RESUMEN

BACKGROUND: Tirzepatide is a dual glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 (GLP-1) receptor agonist that is under development for the treatment of type 2 diabetes. The efficacy and safety of once-weekly tirzepatide as compared with semaglutide, a selective GLP-1 receptor agonist, are unknown. METHODS: In an open-label, 40-week, phase 3 trial, we randomly assigned 1879 patients, in a 1:1:1:1 ratio, to receive tirzepatide at a dose of 5 mg, 10 mg, or 15 mg or semaglutide at a dose of 1 mg. At baseline, the mean glycated hemoglobin level was 8.28%, the mean age 56.6 years, and the mean weight 93.7 kg. The primary end point was the change in the glycated hemoglobin level from baseline to 40 weeks. RESULTS: The estimated mean change from baseline in the glycated hemoglobin level was -2.01 percentage points, -2.24 percentage points, and -2.30 percentage points with 5 mg, 10 mg, and 15 mg of tirzepatide, respectively, and -1.86 percentage points with semaglutide; the estimated differences between the 5-mg, 10-mg, and 15-mg tirzepatide groups and the semaglutide group were -0.15 percentage points (95% confidence interval [CI], -0.28 to -0.03; P = 0.02), -0.39 percentage points (95% CI, -0.51 to -0.26; P<0.001), and -0.45 percentage points (95% CI, -0.57 to -0.32; P<0.001), respectively. Tirzepatide at all doses was noninferior and superior to semaglutide. Reductions in body weight were greater with tirzepatide than with semaglutide (least-squares mean estimated treatment difference, -1.9 kg, -3.6 kg, and -5.5 kg, respectively; P<0.001 for all comparisons). The most common adverse events were gastrointestinal and were primarily mild to moderate in severity in the tirzepatide and semaglutide groups (nausea, 17 to 22% and 18%; diarrhea, 13 to 16% and 12%; and vomiting, 6 to 10% and 8%, respectively). Of the patients who received tirzepatide, hypoglycemia (blood glucose level, <54 mg per deciliter) was reported in 0.6% (5-mg group), 0.2% (10-mg group), and 1.7% (15-mg group); hypoglycemia was reported in 0.4% of those who received semaglutide. Serious adverse events were reported in 5 to 7% of the patients who received tirzepatide and in 3% of those who received semaglutide. CONCLUSIONS: In patients with type 2 diabetes, tirzepatide was noninferior and superior to semaglutide with respect to the mean change in the glycated hemoglobin level from baseline to 40 weeks. (Funded by Eli Lilly; SURPASS-2 ClinicalTrials.gov number, NCT03987919.).


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Polipéptido Inhibidor Gástrico/administración & dosificación , Péptidos Similares al Glucagón/administración & dosificación , Hipoglucemiantes/administración & dosificación , Glucemia/análisis , Diabetes Mellitus Tipo 2/sangre , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Quimioterapia Combinada , Femenino , Polipéptido Inhibidor Gástrico/efectos adversos , Receptor del Péptido 1 Similar al Glucagón/agonistas , Péptidos Similares al Glucagón/efectos adversos , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Incretinas/uso terapéutico , Inyecciones Subcutáneas , Masculino , Metformina/uso terapéutico , Persona de Mediana Edad , Náusea/inducido químicamente , Pérdida de Peso/efectos de los fármacos
2.
Crit Care Med ; 51(11): 1502-1514, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37283558

RESUMEN

OBJECTIVES: Iatrogenic withdrawal syndrome (IWS) associated with opioid and sedative use for medical purposes has a reported high prevalence and associated morbidity. This study aimed to determine the prevalence, utilization, and characteristics of opioid and sedative weaning and IWS policies/protocols in the adult ICU population. DESIGN: International, multicenter, observational, point prevalence study. SETTING: Adult ICUs. PATIENTS: All patients aged 18 years and older in the ICU on the date of data collection who received parenteral opioids or sedatives in the previous 24 hours. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: ICUs selected 1 day for data collection between June 1 and September 30, 2021. Patient demographic data, opioid and sedative medication use, and weaning and IWS assessment data were collected for the previous 24 hours. The primary outcome was the proportion of patients weaned from opioids and sedatives using an institutional policy/protocol on the data collection day. There were 2,402 patients in 229 ICUs from 11 countries screened for opioid and sedative use; 1,506 (63%) patients received parenteral opioids, and/or sedatives in the previous 24 hours. There were 90 (39%) ICUs with a weaning policy/protocol which was used in 176 (12%) patients, and 23 (10%) ICUs with an IWS policy/protocol which was used in 9 (0.6%) patients. The weaning policy/protocol for 47 (52%) ICUs did not define when to initiate weaning, and the policy/protocol for 24 (27%) ICUs did not specify the degree of weaning. A weaning policy/protocol was used in 34% (176/521) and IWS policy/protocol in 9% (9/97) of patients admitted to an ICU with such a policy/protocol. Among 485 patients eligible for weaning policy/protocol utilization based on duration of opioid/sedative use initiation criterion within individual ICU policies/protocols 176 (36%) had it used, and among 54 patients on opioids and/or sedatives ≥ 72 hours, 9 (17%) had an IWS policy/protocol used by the data collection day. CONCLUSIONS: This international observational study found that a small proportion of ICUs use policies/protocols for opioid and sedative weaning or IWS, and even when these policies/protocols are in place, they are implemented in a small percentage of patients.


Asunto(s)
Analgesia , Síndrome de Abstinencia a Sustancias , Niño , Humanos , Adulto , Analgésicos Opioides/efectos adversos , Enfermedad Crítica/terapia , Destete , Unidades de Cuidado Intensivo Pediátrico , Hipnóticos y Sedantes/efectos adversos , Síndrome de Abstinencia a Sustancias/epidemiología , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Enfermedad Iatrogénica/epidemiología , Enfermedad Iatrogénica/prevención & control
3.
Nature ; 529(7586): 368-72, 2016 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-26760209

RESUMEN

Although water vapour is the main species observed in the coma of comet 67P/Churyumov-Gerasimenko and water is the major constituent of cometary nuclei, limited evidence for exposed water-ice regions on the surface of the nucleus has been found so far. The absence of large regions of exposed water ice seems a common finding on the surfaces of many of the comets observed so far. The nucleus of 67P/Churyumov-Gerasimenko appears to be fairly uniformly coated with dark, dehydrated, refractory and organic-rich material. Here we report the identification at infrared wavelengths of water ice on two debris falls in the Imhotep region of the nucleus. The ice has been exposed on the walls of elevated structures and at the base of the walls. A quantitative derivation of the abundance of ice in these regions indicates the presence of millimetre-sized pure water-ice grains, considerably larger than in all previous observations. Although micrometre-sized water-ice grains are the usual result of vapour recondensation in ice-free layers, the occurrence of millimetre-sized grains of pure ice as observed in the Imhotep debris falls is best explained by grain growth by vapour diffusion in ice-rich layers, or by sintering. As a consequence of these processes, the nucleus can develop an extended and complex coating in which the outer dehydrated crust is superimposed on layers enriched in water ice. The stratigraphy observed on 67P/Churyumov-Gerasimenko is therefore the result of evolutionary processes affecting the uppermost metres of the nucleus and does not necessarily require a global layering to have occurred at the time of the comet's formation.


Asunto(s)
Medio Ambiente Extraterrestre/química , Hielo/análisis , Meteoroides , Difusión , Gases/análisis , Gases/química , Análisis Espectral
4.
BMC Evol Biol ; 19(1): 6, 2019 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-30621593

RESUMEN

BACKGROUND: Clupeid fisheries in Lake Tanganyika (East Africa) provide food for millions of people in one of the world's poorest regions. Due to climate change and overfishing, the clupeid stocks of Lake Tanganyika are declining. We investigate the population structure of the Lake Tanganyika sprat Stolothrissa tanganicae, using for the first time a genomic approach on this species. This is an important step towards knowing if the species should be managed separately or as a single stock. Population structure is important for fisheries management, yet understudied for many African freshwater species. We hypothesize that distinct stocks of S. tanganicae could be present due to the large size of the lake (isolation by distance), limnological variation (adaptive evolution), or past separation of the lake (historical subdivision). On the other hand, high mobility of the species and lack of obvious migration barriers might have resulted in a homogenous population. RESULTS: We performed a population genetic study on wild-caught S. tanganicae through a combination of mitochondrial genotyping (96 individuals) and RAD sequencing (83 individuals). Samples were collected at five locations along a north-south axis of Lake Tanganyika. The mtDNA data had low global FST and, visualised in a haplotype network, did not show phylogeographic structure. RAD sequencing yielded a panel of 3504 SNPs, with low genetic differentiation (FST = 0.0054; 95% CI: 0.0046-0.0066). PCoA, fineRADstructure and global FST suggest a near-panmictic population. Two distinct groups are apparent in these analyses (FST = 0.1338 95% CI: 0.1239,0.1445), which do not correspond to sampling locations. Autocorrelation analysis showed a slight increase in genetic difference with increasing distance. No outlier loci were detected in the RADseq data. CONCLUSION: Our results show at most very weak geographical structuring of the stock and do not provide evidence for genetic adaptation to historical or environmental differences over a north-south axis. Based on these results, we advise to manage the stock as one population, integrating one management strategy over the four riparian countries. These results are a first comprehensive study on the population structure of these important fisheries target species, and can guide fisheries management.


Asunto(s)
Conservación de los Recursos Naturales , Explotaciones Pesqueras , Peces/genética , Genética de Población , Genoma , Lagos , Animales , Secuencia de Bases , ADN Mitocondrial/genética , Análisis Discriminante , Sitios Genéticos , Haplotipos/genética , Filogeografía , Polimorfismo de Nucleótido Simple/genética , Análisis de Componente Principal , Tanzanía
5.
EMBO Rep ; 17(11): 1565-1577, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27621284

RESUMEN

Phytochromes constitute a major photoreceptor family found in plants, algae, fungi, and prokaryotes, including pathogens. Here, we report that Xanthomonas campestris pv. campestris (Xcc), the causal agent of black rot disease which affects cruciferous crops worldwide, codes for a functional bacteriophytochrome (XccBphP). XccBphP possesses an N-terminal PAS2-GAF-PHY photosensory domain triad and a C-terminal PAS9 domain as its output module. Our results show that illumination of Xcc, prior to plant infection, attenuates its virulence in an XccBphP-dependent manner. Moreover, in response to light, XccBphP downregulates xanthan exopolysaccharide production and biofilm formation, two known Xcc virulence factors. Furthermore, the XccbphP null mutant shows enhanced virulence, similar to that of dark-adapted Xcc cultures. Stomatal aperture regulation and callose deposition, both well-established plant defense mechanisms against bacterial pathogens, are overridden by the XccbphP strain. Additionally, an RNA-Seq analysis reveals that far-red light or XccBphP overexpression produces genomewide transcriptional changes, including the inhibition of several Xcc virulence systems. Our findings indicate that Xcc senses light through XccBphP, eliciting bacterial virulence attenuation via downregulation of bacterial virulence factors. The capacity of XccBphP to respond to light both in vitro and in vivo was abolished by a mutation on the conserved Cys13 residue. These results provide evidence for a novel bacteriophytochrome function affecting an infectious process.


Asunto(s)
Proteínas Bacterianas/genética , Fitocromo/metabolismo , Enfermedades de las Plantas/microbiología , Xanthomonas campestris/metabolismo , Xanthomonas campestris/patogenicidad , Biopelículas/crecimiento & desarrollo , Productos Agrícolas , Regulación Bacteriana de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Luz , Mutación , Polisacáridos Bacterianos/biosíntesis , Polisacáridos Bacterianos/metabolismo , Factores de Virulencia/genética , Xanthomonas campestris/genética
6.
Ann Oncol ; 28(1): 169-174, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28177438

RESUMEN

Background: TG4023 is a modified vaccinia virus Ankara (MVA) containing the yeast-originated transgene FCU1, expressing cytosine deaminase and uracil phosphoribosyltransferase enzymes that transform the prodrug flucytosine (5-FC) into cytotoxic 5-fluorouracil (5-FU) and 5-fluorouridine-5'-monophosphate, respectively. This first-in-human study aimed to assess the maximum tolerated dose (MTD) of intratumoral (IT) TG4023 and the safety, feasibility, and proof-of-concept (PoC) of TG4023/5-FC combination to deliver high 5-FU concentrations in tumors. Patients and Methods: Cancer patients without further therapeutic option and with at least one injectable primary or metastatic liver tumor underwent on day 1 a percutaneous IT injection of TG4023 at doses of 107, 108, or 4.108 plaque forming units (p.f.u.) using ultrasound imaging guidance, after a dose-limiting toxicities (DLTs)-driven 3 + 3 dose-escalating design. On day 2, patients were given intravenous and/or oral 5-FC at a dose of 200 mg/kg/day for 14 days and were followed for safety through day 43. Tumor response was assessed at week 6, according to RECIST. Plasma and tumor 5-FU concentrations were measured to establish the PoC. Results: In total, 16 patients completed treatment with TG4023 and 5-FC. One DLT/7 patients (ALT/aspartate aminotransferase transient increase) was observed at 4 × 108 p.f.u.; MTD was therefore not reached. The most frequent adverse events were pyrexia, asthenia, vomiting, and decreased appetite. Eight of 16 patients had stable disease. Mean 5-FU concentrations in plasma were 1.9 ± 2.6 ng/ml and 56 ± 30 ng/g in tumors. Seroconversion for anti-FCU1 antibodies was found for one patient from each cohort (16%, overall). Conclusions: This phase I study demonstrated that IT injections of TG4023 were feasible and well tolerated; MTD was defined as 4 × 108 p.f.u. Therapeutic 5-FU concentrations in tumors established the virus-directed enzyme-prodrug therapy PoC. Clinicaltrials.gov Number: NCT00978107.


Asunto(s)
Citosina Desaminasa/genética , Flucitosina/uso terapéutico , Terapia Genética/métodos , Vectores Genéticos/administración & dosificación , Vectores Genéticos/genética , Neoplasias Hepáticas/terapia , Pentosiltransferasa/genética , Adulto , Anciano , Anciano de 80 o más Años , Terapia Combinada , Citosina Desaminasa/metabolismo , Femenino , Flucitosina/farmacocinética , Fluorouracilo/sangre , Fluorouracilo/farmacocinética , Humanos , Inyecciones Intralesiones , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Masculino , Persona de Mediana Edad , Pentosiltransferasa/metabolismo , Prueba de Estudio Conceptual , Transgenes , Virus Vaccinia/genética
7.
PLoS Pathog ; 11(4): e1004818, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25927232

RESUMEN

Uropathogenic E. coli (UPEC) is the primary cause of urinary tract infections (UTI) affecting approximately 150 million people worldwide. Here, we revealed the importance of transcriptional regulator hypoxia-inducible factor-1 α subunit (HIF-1α) in innate defense against UPEC-mediated UTI. The effects of AKB-4924, a HIF-1α stabilizing agent, were studied using human uroepithelial cells (5637) and a murine UTI model. UPEC adherence and invasion were significantly reduced in 5637 cells when HIF-1α protein was allowed to accumulate. Uroepithelial cells treated with AKB-4924 also experienced reduced cell death and exfoliation upon UPEC challenge. In vivo, fewer UPEC were recovered from the urine, bladders and kidneys of mice treated transurethrally with AKB-4924, whereas increased bacteria were recovered from bladders of mice with a HIF-1α deletion. Bladders and kidneys of AKB-4924 treated mice developed less inflammation as evidenced by decreased pro-inflammatory cytokine release and neutrophil activity. AKB-4924 impairs infection in uroepithelial cells and bladders, and could be correlated with enhanced production of nitric oxide and antimicrobial peptides cathelicidin and ß-defensin-2. We conclude that HIF-1α transcriptional regulation plays a key role in defense of the urinary tract against UPEC infection, and that pharmacological HIF-1α boosting could be explored further as an adjunctive therapy strategy for serious or recurrent UTI.


Asunto(s)
Infecciones por Escherichia coli/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inmunidad Innata , Infecciones Urinarias/metabolismo , Escherichia coli Uropatógena/inmunología , Urotelio/metabolismo , Administración Intravesical , Animales , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Péptidos Catiónicos Antimicrobianos/agonistas , Péptidos Catiónicos Antimicrobianos/metabolismo , Adhesión Bacteriana/efectos de los fármacos , Línea Celular , Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/prevención & control , Femenino , Interacciones Huésped-Patógeno/efectos de los fármacos , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/agonistas , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Inmunidad Innata/efectos de los fármacos , Ratones Endogámicos C57BL , Ratones Noqueados , Óxido Nítrico/agonistas , Óxido Nítrico/metabolismo , Piperazinas/administración & dosificación , Piperazinas/farmacología , Piperazinas/uso terapéutico , Estabilidad Proteica/efectos de los fármacos , Piridonas/administración & dosificación , Piridonas/farmacología , Piridonas/uso terapéutico , ARN Mensajero/metabolismo , Infecciones Urinarias/inmunología , Infecciones Urinarias/microbiología , Infecciones Urinarias/prevención & control , Escherichia coli Uropatógena/efectos de los fármacos , Urotelio/efectos de los fármacos , Urotelio/inmunología , Urotelio/microbiología
8.
Mol Ecol ; 26(6): 1557-1575, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28052431

RESUMEN

Quantitative traits important to organismal function and fitness, such as brain size, are presumably controlled by many small-effect loci. Deciphering the genetic architecture of such traits with traditional quantitative trait locus (QTL) mapping methods is challenging. Here, we investigated the genetic architecture of brain size (and the size of five different brain parts) in nine-spined sticklebacks (Pungitius pungitius) with the aid of novel multilocus QTL-mapping approaches based on a de-biased LASSO method. Apart from having more statistical power to detect QTL and reduced rate of false positives than conventional QTL-mapping approaches, the developed methods can handle large marker panels and provide estimates of genomic heritability. Single-locus analyses of an F2 interpopulation cross with 239 individuals and 15 198, fully informative single nucleotide polymorphisms (SNPs) uncovered 79 QTL associated with variation in stickleback brain size traits. Many of these loci were in strong linkage disequilibrium (LD) with each other, and consequently, a multilocus mapping of individual SNPs, accounting for LD structure in the data, recovered only four significant QTL. However, a multilocus mapping of SNPs grouped by linkage group (LG) identified 14 LGs (1-6 depending on the trait) that influence variation in brain traits. For instance, 17.6% of the variation in relative brain size was explainable by cumulative effects of SNPs distributed over six LGs, whereas 42% of the variation was accounted for by all 21 LGs. Hence, the results suggest that variation in stickleback brain traits is influenced by many small-effect loci. Apart from suggesting moderately heritable (h2  ≈ 0.15-0.42) multifactorial genetic architecture of brain traits, the results highlight the challenges in identifying the loci contributing to variation in quantitative traits. Nevertheless, the results demonstrate that the novel QTL-mapping approach developed here has distinctive advantages over the traditional QTL-mapping methods in analyses of dense marker panels.


Asunto(s)
Encéfalo , Mapeo Cromosómico , Tipificación de Secuencias Multilocus , Smegmamorpha/genética , Animales , Genómica/métodos , Desequilibrio de Ligamiento , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo
9.
PLoS Pathog ; 10(1): e1003846, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24391502

RESUMEN

Group B Streptococcus (GBS) is a common agent of bacterial sepsis and meningitis in newborns. The GBS surface capsule contains sialic acids (Sia) that engage Sia-binding immunoglobulin-like lectins (Siglecs) on leukocytes. Here we use mice lacking Siglec-E, an inhibitory Siglec of myelomonocytic cells, to study the significance of GBS Siglec engagement during in vivo infection. We found GBS bound to Siglec-E in a Sia-specific fashion to blunt NF-κB and MAPK activation. As a consequence, Siglec-E-deficient macrophages had enhanced pro-inflammatory cytokine secretion, phagocytosis and bactericidal activity against the pathogen. Following pulmonary or low-dose intravenous GBS challenge, Siglec-E KO mice produced more pro-inflammatory cytokines and exhibited reduced GBS invasion of the central nervous system. In contrast, upon high dose lethal challenges, cytokine storm in Siglec-E KO mice was associated with accelerated mortality. We conclude that GBS Sia mimicry influences host innate immune and inflammatory responses in vivo through engagement of an inhibitory Siglec, with the ultimate outcome of the host response varying depending upon the site, stage and magnitude of infection.


Asunto(s)
Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos B/inmunología , Imitación Molecular/inmunología , Ácido N-Acetilneuramínico/inmunología , Neumonía Bacteriana/inmunología , Infecciones Estreptocócicas/inmunología , Streptococcus agalactiae/inmunología , Animales , Antígenos CD/genética , Antígenos de Diferenciación de Linfocitos B/genética , Citocinas/genética , Citocinas/inmunología , Humanos , Inflamación/genética , Inflamación/inmunología , Inflamación/patología , Macrófagos/inmunología , Macrófagos/patología , Ratones , Ratones Noqueados , Ácido N-Acetilneuramínico/genética , Neumonía Bacteriana/genética , Neumonía Bacteriana/patología , Infecciones Estreptocócicas/genética , Infecciones Estreptocócicas/patología
10.
Cerebrovasc Dis ; 42(1-2): 57-65, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26986943

RESUMEN

BACKGROUND: With regard to acute stroke, patients with unknown time from stroke onset are not eligible for thrombolysis. Quantitative diffusion weighted imaging (DWI) and fluid attenuated inversion recovery (FLAIR) MRI relative signal intensity (rSI) biomarkers have been introduced to predict eligibility for thrombolysis, but have shown heterogeneous results in the past. In the present work, we investigated whether the inclusion of easily obtainable clinical-radiological parameters would improve the prediction of the thrombolysis time window by rSIs and compared their performance to the visual DWI-FLAIR mismatch. METHODS: In a retrospective study, patients from 2 centers with proven stroke with onset <12 h were included. The DWI lesion was segmented and overlaid on ADC and FLAIR images. rSI mean and SD, were calculated as follows: (mean ROI value/mean value of the unaffected hemisphere). Additionally, the visual DWI-FLAIR mismatch was evaluated. Prediction of the thrombolysis time window was evaluated by the area-under-the-curve (AUC) derived from receiver operating characteristic (ROC) curve analysis. Factors such as the association of age, National Institutes of Health Stroke Scale, MRI field strength, lesion size, vessel occlusion and Wahlund-Score with rSI were investigated and the models were adjusted and stratified accordingly. RESULTS: In 82 patients, the unadjusted rSI measures DWI-mean and -SD showed the highest AUCs (AUC 0.86-0.87). Adjustment for clinical-radiological covariates significantly improved the performance of FLAIR-mean (0.91) and DWI-SD (0.91). The best prediction results based on the AUC were found for the final stratified and adjusted models of DWI-SD (0.94) and FLAIR-mean (0.96) and a multivariable DWI-FLAIR model (0.95). The adjusted visual DWI-FLAIR mismatch did not perform in a significantly worse manner (0.89). ADC-rSIs showed fair performance in all models. CONCLUSIONS: Quantitative DWI and FLAIR MRI biomarkers as well as the visual DWI-FLAIR mismatch provide excellent prediction of eligibility for thrombolysis in acute stroke, when easily obtainable clinical-radiological parameters are included in the prediction models.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Fibrinolíticos/administración & dosificación , Accidente Cerebrovascular/diagnóstico por imagen , Terapia Trombolítica , Tiempo de Tratamiento , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Circulación Cerebrovascular , Distribución de Chi-Cuadrado , Toma de Decisiones Clínicas , Esquema de Medicación , Femenino , Alemania , Humanos , Interpretación de Imagen Asistida por Computador , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Selección de Paciente , Valor Predictivo de las Pruebas , Curva ROC , Estudios Retrospectivos , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo
11.
J Stroke Cerebrovasc Dis ; 25(6): 1544-51, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27053027

RESUMEN

BACKGROUND: Prompt diagnosis of vessel pathology and appropriate treatment of moyamoya vasculopathy (MMV) are essential to improve long-term prognosis. The aims of our study were to explore the diagnostic value of ultra-high-field (UHF) magnetic resonance imaging at 7.0 T in MMV patients and to compare the applicability of two different 7.0 T vessel imaging modalities to 3.0 T magnetic resonance angiography (MRA) and digital subtraction angiography (DSA). METHODS: In a World Health Organization-registered and prospective imaging trial, patients were investigated at 7.0 T magnetization-prepared rapid-acquisition gradient echo (MPRAGE)-MRA and time-of-flight (TOF)-MRA, 3.0 T TOF-MRA, and by DSA. RESULTS: Six patients were included in our study and evaluated for MMV. 3.0 T TOF-MRA and 7.0 T MPRAGE-MRA were able to depict the complete major vascular tree and confirmed MMV-specific steno-occlusions of major intracranial arteries, as previously identified by DSA. 7.0 T TOF-MRA was limited to visualization of the circle of Willis as well as the internal carotid artery only. Donor vessels for bypass surgery (i.e., branches of superficial temporal artery) could be sufficiently visualized with all magnetic resonance modalities. CONCLUSIONS: Our results indicate that a specific 7.0 T vascular imaging protocol yields diagnostic information about vessel pathology in MMV that approximates conventional DSA. 7.0 T MPRAGE was superior to 7.0 T TOF-MRA due to shorter scanning times and better brain coverage. To date, however, limited availability of 7.0 T technology in medical facilities as well as technical and procedural constraints excludes a fair amount of patients from the clinical 7.0 T imaging process.


Asunto(s)
Angiografía de Substracción Digital , Angiografía Cerebral/métodos , Arterias Cerebrales/diagnóstico por imagen , Angiografía por Resonancia Magnética , Enfermedad de Moyamoya/diagnóstico por imagen , Adolescente , Adulto , Arterias Cerebrales/patología , Arterias Cerebrales/cirugía , Ensayos Clínicos como Asunto , Femenino , Humanos , Masculino , Enfermedad de Moyamoya/patología , Enfermedad de Moyamoya/cirugía , Proyectos Piloto , Valor Predictivo de las Pruebas , Pronóstico , Reproducibilidad de los Resultados , Adulto Joven
12.
Stroke ; 46(10): 2795-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26306755

RESUMEN

BACKGROUND AND PURPOSE: Dynamic susceptibility-weighted contrast-enhanced (DSC) magnetic resonance imaging (MRI) is used to identify the tissue-at-risk in acute stroke, but the choice of optimal DSC postprocessing in the clinical setting remains a matter of debate. Using 15O-water positron emission tomography (PET), we validated the performance of 2 common deconvolution methods for DSC-MRI. METHODS: In (sub)acute stroke patients with consecutive MRI and PET imaging, DSC maps were calculated applying 2 deconvolution methods, standard and block-circulant single value decomposition. We used 2 standardized analysis methods, a region of interest-based and a voxel-based analysis, where PET cerebral blood flow masks of <20 mL/100 g per minute (penumbral flow) and gray matter masks were overlaid on DSC parameter maps. For both methods, receiver operating characteristic curve analysis was performed to identify the accuracy of each DSC-MR map for the detection of PET penumbral flow. RESULTS: In 18 data sets (median time after stroke onset: 18 hours; median time PET to MRI: 101 minutes), block-circulant single value decomposition showed significantly better performance to detect PET penumbral flow only for mean transit time maps. Time-to-maximum (Tmax) had the highest performance independent of the deconvolution method. CONCLUSIONS: Block-circulant single value decomposition seems only significantly beneficial for mean transit time maps in (sub)acute stroke. Tmax is likely the most stable deconvolved parameter for the detection of tissue-at-risk using DSC-MRI.


Asunto(s)
Encéfalo/irrigación sanguínea , Encéfalo/patología , Interpretación de Imagen Asistida por Computador/métodos , Accidente Cerebrovascular/patología , Adulto , Anciano , Área Bajo la Curva , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Curva ROC , Estudios Retrospectivos
13.
Cell Microbiol ; 16(9): 1425-40, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24779357

RESUMEN

Some intracellular bacteria are known to cause long-term infections that last decades without compromising the viability of the host. Although of critical importance, the adaptations that intracellular bacteria undergo during this long process of residence in a host cell environment remain obscure. Here, we report a novel experimental approach to study the adaptations of mycobacteria imposed by a long-term intracellular lifestyle. Selected Mycobacterium bovis BCG through continuous culture in macrophages underwent an adaptation process leading to impaired phenolic glycolipids (PGL) synthesis, improved usage of glucose as a carbon source and accumulation of neutral lipids. These changes correlated with increased survival of mycobacteria in macrophages and mice during re-infection and also with the specific expression of stress- and survival-related genes. Our findings identify bacterial traits implicated in the establishment of long-term cellular infections and represent a tool for understanding the physiological states and the environment that bacteria face living in fluctuating intracellular environments.


Asunto(s)
Macrófagos/microbiología , Infecciones por Mycobacterium/microbiología , Mycobacterium/fisiología , Animales , Femenino , Glucolípidos/metabolismo , Ratones , Ratones Endogámicos BALB C , Mycobacterium/aislamiento & purificación , Mycobacterium bovis/fisiología
14.
J Biol Chem ; 288(9): 6417-26, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23322784

RESUMEN

Staphylococcus aureus infections present an enormous global health concern complicated by an alarming increase in antibiotic resistance. S. aureus is among the few bacterial species that express nitric-oxide synthase (bNOS) and thus can catalyze NO production from L-arginine. Here we generate an isogenic bNOS-deficient mutant in the epidemic community-acquired methicillin-resistant S. aureus (MRSA) USA300 clone to study its contribution to virulence and antibiotic susceptibility. Loss of bNOS increased MRSA susceptibility to reactive oxygen species and host cathelicidin antimicrobial peptides, which correlated with increased MRSA killing by human neutrophils and within neutrophil extracellular traps. bNOS also promoted resistance to the pharmaceutical antibiotics that act on the cell envelope such as vancomycin and daptomycin. Surprisingly, bNOS-deficient strains gained resistance to aminoglycosides, suggesting that the role of bNOS in antibiotic susceptibility is more complex than previously observed in Bacillus species. Finally, the MRSA bNOS mutant showed reduced virulence with decreased survival and smaller abscess generation in a mouse subcutaneous infection model. Together, these data indicate that bNOS contributes to MRSA innate immune and antibiotic resistance phenotypes. Future development of specific bNOS inhibitors could be an attractive option to simultaneously reduce MRSA pathology and enhance its susceptibility to commonly used antibiotics.


Asunto(s)
Proteínas Bacterianas/metabolismo , Resistencia a la Meticilina , Staphylococcus aureus Resistente a Meticilina/enzimología , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Óxido Nítrico Sintasa/metabolismo , Infecciones Cutáneas Estafilocócicas/enzimología , Absceso/genética , Absceso/microbiología , Absceso/patología , Animales , Antibacterianos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Proteínas Bacterianas/genética , Daptomicina/farmacología , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , Ratones , Mutación , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa/genética , Especies Reactivas de Oxígeno/metabolismo , Infecciones Cutáneas Estafilocócicas/genética , Infecciones Cutáneas Estafilocócicas/microbiología , Infecciones Cutáneas Estafilocócicas/patología , Vancomicina/farmacología , Catelicidinas
15.
Intensive Care Med ; 50(2): 222-233, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38170226

RESUMEN

PURPOSE: The aim of this study was to describe the incidence of venous thromboembolism (VTE) and major bleeding among hospitalized patients with hematologic malignancy, assessing its association with critical illness and other baseline characteristics. METHODS: We conducted a population-based cohort study of hospitalized adults with a new diagnosis of hematologic malignancy in Ontario, Canada, between 2006 and 2017. The primary outcome was VTE (pulmonary embolism or deep venous thrombosis). Secondary outcomes were major bleeding and in-hospital mortality. We compared the incidence of VTE between intensive care unit (ICU) and non-ICU patients and described the association of other baseline characteristics and VTE. RESULTS: Among 76,803 eligible patients (mean age 67 years [standard deviation, SD, 15]), 20,524 had at least one ICU admission. The incidence of VTE was 3.7% in ICU patients compared to 1.2% in non-ICU patients (odds ratio [OR] 3.08; 95% confidence interval [CI] 2.77-3.42). The incidence of major bleeding was 7.6% and 2.4% (OR 3.33; 95% CI 3.09-3.58), respectively. The association of critical illness and VTE remained significant after adjusting for potential confounders (OR 2.92; 95% CI 2.62-3.25). We observed a higher incidence of VTE among specific subtypes of hematologic malignancy and patients with prior VTE (OR 6.64; 95% CI 5.42-8.14). Admission more than 1 year after diagnosis of hematologic malignancy (OR 0.64; 95% CI 0.56-0.74) and platelet count ≤ 50 × 109/L at the time of hospitalization (OR 0.63; 95% CI 0.48-0.84) were associated with a lower incidence of VTE. CONCLUSION: Among patients with hematologic malignancy, critical illness and certain baseline characteristics were associated with a higher incidence of VTE.


Asunto(s)
Neoplasias Hematológicas , Tromboembolia Venosa , Adulto , Humanos , Anciano , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/etiología , Estudios de Cohortes , Enfermedad Crítica , Neoplasias Hematológicas/complicaciones , Neoplasias Hematológicas/epidemiología , Ontario/epidemiología , Hemorragia
16.
Chest ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38901489

RESUMEN

BACKGROUND: Sedative overdoses pose a delirium risk among Intensive Care Unit (ICU) patients, with potential mitigation through the use of a processed EEG monitor (BIS) to guide depth of sedation. RESEARCH QUESTION: Can BIS-guided deep sedation (RASS -4, -5) reduce sedative dosage and increase delirium-free and coma-free (DFCF) days? STUDY DESIGN AND METHODS: A randomized controlled trial was conducted in a tertiary mixed ICU, enrolling patients requiring deep sedation for >8 hours. Patients were randomly assigned to either the Clinical Assessment (CA) or BIS groups (BIS range of 40-60). Both groups utilized a BIS sensor, while the CA group's screen remained covered. After deep sedation, BIS sensors were removed, and delirium was assessed twice daily by researchers blinded to the randomization. The primary outcome was the number of DFCF days within 14 days after deep sedation. Additionally, we compared doses of sedative drugs and BIS values during deep sedation. RESULTS: Ninety-nine patients were included in the study. We found no significant difference in DFCF (p=0.1) between CA and BIS arms, but propofol doses were significantly lower in the BIS group (CA group 1.77 mg/kg/hr [95% CI 1.60, 1.93] vs. BIS group 1.44 mg/kg/hr [95% CI 1.04, 1.83]; p=0.03). During deep sedation, the CA group spent 46% of the total hours (95% CI 35, 57%) with BIS values below 40, whereas the BIS group spent 32% (95% CI 25, 40%), (p=0.03). Subgroup analysis focusing on patients sedated for more than 24 hours revealed an increase in DFCF in the BIS group (CA group median of 1 day [IQR 0, 9] vs. BIS group 8 days [IQR 0, 13]; p=0.04). INTERPRETATION: BIS-guided deep sedation did not improve DFCF days but reduced sedative drug use. In patients requiring sedation for more than 24 hours, it showed an improvement in DFCF days.

17.
Artículo en Inglés | MEDLINE | ID: mdl-38906793

RESUMEN

OBJECTIVE: Our objectives were to describe the use of thromboprophylaxis and the incidence of VTE/bleeding in critically ill patients with hematologic malignancies (HM). DESIGN: Retrospective cohort study (2014-2022). SETTING: Medic-Surgical Intensive Care Unit (ICU) in a tertiary care academic center. PATIENTS: Adult patients admitted to ICU with a concomitant diagnosis of a hematological malignancy. INTERVENTIONS: None. MAIN VARIABLES OF INTEREST: We analyzed demographic data, use of thromboprophylaxis and secondary outcomes that included incidence of VTE (venous thromboembolism), bleeding, mortality, severity scores and organ support. We applied a multivariable logistic regression model to examine the risk of thrombosis in the ICU. RESULTS: We included 862 ICU admissions (813 unique patients). Thromboprophylaxis was given during 65% of admissions (LMWH 14%, UFH 8%, and SCDs 43%); in 21% it was contraindicated due to thrombocytopenia; 14% of cases lacked documentation on prophylaxis. There were 38 unique incident cases of VTE (27 DVT, 11 PE), constituting 4.4% of ICU episodes. Most of VTE cases happened in patients with various degrees of thrombocytopenia. In the multivariable analysis, SOFA score on the first ICU day was independently associated (OR 0.85, 95% CI 0.76-0.96) with the risk of VTE. Bleeding occurred in 7.2% (minor) and 14.4% (major) of episodes; most frequent sites being CNS, abdomen/GI and pulmonary. CONCLUSIONS: In this cohort of critically ill patients with HM, there was considerable variability in the utilization of DVT prophylaxis, with predominant use of SCDs. The incidence of VTE was 4.4% and major bleeding 14%. CLINICAL TRIAL REGISTRATION: NCT05396157. Venous Thromboembolism in Hematologic Malignancy and Hematopoietic Cell Transplant Patients: a Retrospective Study (https://clinicaltrials.gov/).

18.
J Neurooncol ; 113(2): 229-38, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23525950

RESUMEN

Previous studies have shown an inverse association between allergies and glioma risk; however, results for associations between single nucleotide polymorphisms (SNPs) of allergy-related genes and glioma risk have been inconsistent and restricted to a small number of SNPs. The objective of this study was to examine the association between 166 SNPs of 21 allergy-related genes and glioma risk in a nested case-control study of participants from three large US prospective cohort studies. Blood collection took place between 1982 and 1994 among the 562 included Caucasian participants (143 cases and 419 matched controls) prior to case diagnosis. Custom Illumina assay chips were used for genotyping. Logistic regression analyses, controlling for age and study cohort, were used to determine associations between each SNP and glioma risk. Statistically significant associations were found between rs2494262 and rs2427824 of the FCER1A gene, which encodes the alpha chain of the high affinity immunoglobulin E receptor, and glioma risk (nominal trend p values 0.01 and 0.03, respectively). Significant associations were also found between SNPs in IL10, ADAM33, NOS1 and IL4R and glioma risk. However, our analyses were not corrected for multiple comparisons and need to be interpreted with caution. Our findings with FCER1A SNPs provide further support for the link between allergies and risk of glioma.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Encefálicas/etiología , Glioma/etiología , Hipersensibilidad/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Anciano , Estudios de Casos y Controles , ADN/genética , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Riesgo
19.
J Vet Res ; 67(1): 55-60, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37008763

RESUMEN

Introduction: Mycobacterium bovis and Mycobacterium avium subsp. paratuberculosis, respectively the causative agents of bovine tuberculosis (bTB) and bovine paratuberculosis (PTB), share a high number of antigenic proteins. This characteristics makes the differential diagnosis of the diseases difficult. The interferon gamma (IFN-γ), C-X-C motif chemokine ligand 10 (CXCL10), matrix metallopeptidase 9 (MMP9), interleukin 22 (IL-22) and thrombospondin 1 (THBS1) bovine genes have already been shown to be accurate transcriptional biomarkers of bTB. In order to improve the diagnosis of bTB and PTB, in the present study we evaluated the risk of false positivity of these bTB biomarkers in cattle with PTB. Material and Methods: The transcription of these genes was studied in 13 PTB-infected cattle, using Mycobacterium avium subsp. paratuberculosis (MAP)-stimulated peripheral blood mononuclear cells (PBMC). Results: Overall, the levels of IFN-γ, CXCL10, MMP9 and IL-22 transcripts in MAP-stimulated PBMC failed to differentiate animals with PTB from healthy animals. However, as bTB-afflicted cattle do, the MAP-infected group also displayed a lower level of THBS1 transcription than the non-infected animals. Conclusion: The results of this study add new specificity attributes to the levels of transcription of IFN-γ, CXCL10, MMP9 and IL-22 as biomarkers for bTB.

20.
Future Microbiol ; 18: 1381-1398, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37962486

RESUMEN

Almost 3% of the proteins of Mycobacterium tuberculosis (M. tuberculosis), the main causative agent of human tuberculosis, are lipoproteins. These lipoproteins are characteristic of the mycobacterial cell envelope and participate in many mechanisms involved in the pathogenesis of M. tuberculosis. In this review, the authors provide an updated analysis of M. tuberculosis lipoproteins and categorize them according to their demonstrated or predicted functions, including transport of compounds to and from the cytoplasm, biosynthesis of the mycobacterial cell envelope, defense and resistance mechanisms, enzymatic activities and signaling pathways. In addition, this updated analysis revealed that at least 40% of M. tuberculosis lipoproteins are glycosylated.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Tuberculosis/microbiología , Membrana Celular , Pared Celular/metabolismo , Lipoproteínas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
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