24 research outputs found
Yersinia Has a Tropism for B and T Cell Zones of Lymph Nodes That Is Independent of the Type III Secretion System
Pathogenic Yersinia have a pronounced tropism for lymphatic tissues and harbor a virulence plasmid that encodes a type III secretion system, pTTSS, that transports Yops into host cells. Yops are critical virulence factors that prevent phagocytosis by macrophages and neutrophils and Yersinia mutants lacking one or more Yops are defective for survival in lymphatic tissues, liver, and gastrointestinal tract. However, here we demonstrate that Y. pseudotuberculosis (Yptb) mutants lacking the pTTSS survived as well as or better than wild-type (WT) Yptb in the mesenteric lymph nodes (MLN). Infection with pTTSS mutants caused lymphadenitis with little necrosis, whereas infection with WT Yptb provoked lymphadenitis with multiple necrotic suppurative foci. Gentamicin protection assays and microscopic examination of the MLN revealed that pTTSS mutants resided extracellularly adjacent to B and T lymphocytes in the cortex and paracortex. WT Yptb was found extracellularly adjacent to neutrophils and macrophages in necrotic areas and adjacent to B and T lymphocytes in less-inflamed areas. To determine whether lymphocytes protected pTTSS mutants from phagocytic cells, Rag1(â/â) mice were infected with pTTSS mutants or WT Yptb. pTTSS mutants but not WT, were impaired for survival in MLN of Rag1(â/â) mice, suggesting that lymphocyte-rich regions constitute a protective niche for pTTSS mutants. Finally, we show that invasin and the chromosomally encoded TTSS were not required for Yptb survival in MLN. In summary, chromosomally encoded factors are sufficient for Yptb replication in the cortex and paracortex of MLN; the pTTSS enables Yersinia to survive within phagocyte-rich areas of lymph nodes, and spread to other tissues
Efficient boron removal by using mesoporous matrices grafted with saccharides
Highly efficient boron removal from water was achieved by using mesoporous silica materials functionalised with saccharides.Beltran Porter, Daniel, [email protected] ; Amoros del Toro, Pedro Jose, [email protected]
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Evaluation of the relationship between slow-waves of intracranial pressure, mean arterial pressure and brain tissue oxygen in TBI: a CENTER-TBI exploratory analysis
Abstract: Brain tissue oxygen (PbtO2) monitoring in traumatic brain injury (TBI) has demonstrated strong associations with global outcome. Additionally, PbtO2 signals have been used to derive indices thought to be associated with cerebrovascular reactivity in TBI. However, their true relationship to slow-wave vasogenic fluctuations associated with cerebral autoregulation remains unclear. The goal of this study was to investigate the relationship between slow-wave fluctuations of intracranial pressure (ICP), mean arterial pressure (MAP) and PbtO2 over time. Using the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) high resolution ICU sub-study cohort, we evaluated those patients with recorded high-frequency digital intra-parenchymal ICP and PbtO2 monitoring data of a minimum of 6 h in duration. Digital physiologic signals were processed for ICP, MAP, and PbtO2 slow-waves using a moving average filter to decimate the high-frequency signal. The first 5 days of recording were analyzed. The relationship between ICP, MAP and PbtO2 slow-waves over time were assessed using autoregressive integrative moving average (ARIMA) and vector autoregressive integrative moving average (VARIMA) modelling, as well as Granger causality testing. A total of 47 patients were included. The ARIMA structure of ICP and MAP were similar in time, where PbtO2 displayed different optimal structure. VARIMA modelling and IRF plots confirmed the strong directional relationship between MAP and ICP, demonstrating an ICP response to MAP impulse. PbtO2 slow-waves, however, failed to demonstrate a definite response to ICP and MAP slow-wave impulses. These results raise questions as to the utility of PbtO2 in the derivation of cerebrovascular reactivity measures in TBI. There is a reproducible relationship between slow-wave fluctuations of ICP and MAP, as demonstrated across various time-series analytic techniques. PbtO2 does not appear to reliably respond in time to slow-wave fluctuations in MAP, as demonstrated on various VARIMA models across all patients. These findings suggest that PbtO2 should not be utilized in the derivation of cerebrovascular reactivity metrics in TBI, as it does not appear to be responsive to changes in MAP in the slow-waves. These findings corroborate previous results regarding PbtO2 based cerebrovascular reactivity indices
Constraint-based naturalistic decision making in mission planning teams
Motivation â To understand the factors acting upon decision making of military planners prior to theintroduction of digital planning systems. Research approach â Participant-observation by the researchteam and direct observation of the planning process on exercises. Findings â Many different disciplinescontribute to the planning process in a co-operative and collaborative manner. Each stage in the planningprocess results in a further set of constraints being applied, each of which offer successive refinement ofthe plan. Research limitations/Implications âThe research is limited to land-based military planning.Originality/Value â This research is based on field observation of military planners with tight deadlinesand a non-compliant opposing force. Take away message â âMilitary planning seems to be more aboutidentification of relevant constraints than optimization of decisions
Two episodes of Taravana syndrome in a breath-hold diver with hyperhomocysteinemia
Key Clinical MessageTaravana syndrome is a rare dysbaric disease characterized by neurologic signs and symptoms. Differently from others decompression illness, it has unspecified pathophysiology and unclear predisposing factors. Our cases suggest that thrombophilic state due to hyperhomocysteinemia could increase the risk to develop Taravana syndrome
Potential Trends in Attention Deficit Hyperactivity Disorder (ADHD) Drug Use on a College Campus: Wastewater Analysis of Amphetamine and Ritalinic Acid
Attention Deficit Hyperactivity Disorder (ADHD) medication use is on the rise in the United States. The most widely used ADHD medications are the amphetamine-type compounds Adderall (mixed amphetamine salts) and Ritalin (methylphenidate). According to survey data ADHD medications are used as a study drug or âSmart Drugâ by students without a prescription on college campuses. Survey data of non-prescribed drug use has limitations with accurate reporting and no empirical data of usage exists in the literature. This study looks for trends in the use of these drugs on a college campus among low-stress and high stress periods. The metabolites of these two drugs, amphetamine and ritalinic acid, are quantified in campus wastewater using solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Trends show a possible increase in amphetamine levels during periods of high stress such as midterms, the last week of classes and finals week over levels from the baseline low stress weeks such as the first week of classes. Both semesters from the 2011-12 academic year were studied and the highest increase over baseline (760%) occurred during finals week of the second semester. Ritalinic acid levels gradually climbed first semester but had no obvious periodic trend second semester
Men's experiences of sexuality after cancer: a material discursive intra-psychic approach
Relationship between the level of anxiety of resident doctors and patient satisfaction in De La Salle University Medical Center Out-Patient Department in January, 2015
This study employed the cross-sectional design. Thirty-four (34) resident doctors who were in different years of training and specialization except psychiatric and pediatrics and their 124 patients who were 20 years old and above, ambulatory, conscious and coherent, and on their first visit who needed healthcare consultation. A self-administered questionnaire was used for data collection. Data was analysed using percentage and frequency. The findings of this study revealed that most of the resident doctors (70.59% or 24 of 35) in DLSUMC OPD had normal anxiety. Majority of the patients (88.80% or 111 or 125) were satisfied to the care rendered to them. Using the statistical tools, results showed that there was a significant relationship between gender of resident doctors and level of anxiety (p=0.0306) as well as between civil status of the patients and patient satisfaction (p=0.0034)