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1.
J Thromb Thrombolysis ; 53(2): 359-362, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34739662

ABSTRACT

Cases of cerebral venous thrombosis (CVT) associated with vaccine induced thrombotic thrombocytopenia (VITT) were reported following administration of the adenoviral vector COVID-19 vaccines, resulting in a pause in Ad.26.COV2.S vaccine administration in the United States, beginning on April 14, 2021. We aimed to quantify and characterize an anticipated increase in brain venograms performed in response to this pause. Brain venogram cases were retrospectively identified during the three-week period following the vaccine pause and during the same calendar period in 2019. For venograms performed in 2021, we compared COVID vaccinated to unvaccinated patients. There was a 262% increase in venograms performed between 2019 (n = 26) and 2021 (n = 94), compared to only a 19% increase in all radiologic studies. Fifty-seven percent of patients in 2021 had a history of COVID-19 vaccination, with the majority being Ad.26.COV2.S. All patients diagnosed with CVT were unvaccinated. COVID vaccinated patients lacked platelet or D-dimer measurements consistent with VITT. Significantly more vaccinated versus unvaccinated patients had a headache (94% vs 70%, p = 0.0014), but otherwise lacked compelling CVT presentations, such as decreased/altered consciousness (7% vs 23%, p = 0.036), neurologic deficit (28% vs 48%, p = 0.049), and current/recent pregnancy (2% vs 28%, p = 0.0003). We found a dramatic increase in brain venograms performed following publicity of rare COVID-19 vaccine associated CVT cases, with no CVTs identified in vaccinated patients. Clinicians should carefully consider if brain venogram performance is indicated in COVID-19 vaccinated patients lacking thrombocytopenia and D-dimer elevation, especially without other compelling CVT risk factors or symptoms.


Subject(s)
COVID-19 Vaccines , COVID-19 , Intracranial Thrombosis , Thrombocytopenia , Thrombosis , Brain , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Humans , Intracranial Thrombosis/etiology , Phlebography/adverse effects , Retrospective Studies , Thrombocytopenia/etiology , Thrombosis/etiology , United States , Vaccination/adverse effects
3.
PLoS One ; 12(9): e0184164, 2017.
Article in English | MEDLINE | ID: mdl-28886135

ABSTRACT

Burn patients suffer from immunological dysfunction for which there are currently no successful interventions. Similar to previous observations, we find that burn shock patients (≥15% Total Burn Surface Area (TBSA) injury) have elevated levels of the innate immune cytokines Interleukin-6 (IL-6) and Monocyte Chemoattractant Protein-1 (MCP-1)/CC-motif Chemokine Ligand 2(CCL2) early after hospital admission (0-48 Hours Post-hospital Admission (HPA). Functional immune assays with patient Peripheral Blood Mononuclear Cells (PBMCs) revealed that burn shock patients (≥15% TBSA) produced elevated levels of MCP-1/CCL2 after innate immune stimulation ex vivo relative to mild burn patients. Interestingly, treatment of patient PBMCs with the Nuclear Factor-Erythroid-2-Related Factor 2 (NRF2) agonist, CDDO-Me(bardoxolone methyl), reduced MCP-1 production but not IL-6 or Interleukin-10 (IL-10) secretion. In enriched monocytes from healthy donors, CDDO-Me(bardoxolone methyl) also reduced LPS-induced MCP1/CCL2 production but did not alter IL-6 or IL-10 secretion. Similar immunomodulatory effects were observed with Compound 7, which activates the NRF2 pathway through a different and non-covalent Mechanism Of Action (MOA). Hence, our findings with CDDO-Me(bardoxolone methyl) and Compound 7 are likely to reflect a generalizable aspect of NRF2 activation. These observed effects were not specific to LPS-induced immune responses, as NRF2 activation also reduced MCP-1/CCL2 production after stimulation with IL-6. Pharmacological NRF2 activation reduced Mcp-1/Ccl2 transcript accumulation without inhibiting either Il-6 or Il-10 transcript levels. Hence, we describe a novel aspect of NRF2 activation that may contribute to the beneficial effects of NRF2 agonists during disease. Our work also demonstrates that the NRF2 pathway is retained and can be modulated to regulate important immunomodulatory functions in burn patient immune cells.


Subject(s)
Burns/immunology , Burns/metabolism , Cytokines/biosynthesis , Immunity, Innate , Lymphocytes/immunology , Lymphocytes/metabolism , Monocytes/immunology , Monocytes/metabolism , NF-E2-Related Factor 2/metabolism , Adult , Burns/mortality , Burns/therapy , Chemokine CCL2/biosynthesis , Cohort Studies , Female , Humans , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Male , Middle Aged
4.
Bioresour Technol ; 102(1): 94-100, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20561783

ABSTRACT

This study demonstrates the production of algal biodiesel from Dunaliella tertiolecta, Nannochloropsis oculata, wild freshwater microalgae, and macroalgae lipids using a highly efficient continuous catalytic process. The heterogeneous catalytic process uses supercritical methanol and porous titania microspheres in a fixed bed reactor to catalyze the simultaneous transesterification and esterification of triacylglycerides and free fatty acids, respectively, to fatty acid methyl esters (biodiesel). Triacylglycerides and free fatty acids were converted to alkyl esters with up to 85% efficiency as measured by 300 MHz (1)H NMR spectroscopy. The lipid composition of the different algae was studied gravimetrically and by gas chromatography. The analysis showed that even though total lipids comprised upwards of 19% of algal dry weight the saponifiable lipids, and resulting biodiesel, comprised only 1% of dry weight. Thus highlighting the need to determine the triacylglyceride and free fatty acid content when considering microalgae for biodiesel production.


Subject(s)
Biofuels , Eukaryota/metabolism , Lipids/chemistry , Methanol/chemical synthesis , Biomass , Bioreactors , Catalysis , Esterification , Esters/chemistry , Fatty Acids, Nonesterified/chemistry , Magnetic Resonance Spectroscopy , Microspheres , Porosity , Temperature , Titanium/chemistry , Triglycerides/chemistry
5.
Electrophoresis ; 30(22): 3846-54, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19876957

ABSTRACT

Cellulose dimethylphenylcarbamate (CDMPC)-immobilized zirconia (CDMPCZ) was used as a chiral stationary phase for enantioseparation of a set of nine racemic compounds in reversed-phase CEC. Influences of the type and composition of organic modifier and the applied voltage on enantioseparation were examined. Separation data on CDMPCZ were also compared with those on CDMPC-immobilized silica (CDMPCS). Enantiomers of the analytes investigated are well separated in ACN/phosphate buffer mobile phases. Better enantioselectivity and resolution were obtained with ACN than MeOH as the organic modifier. Retention was longer but better enantioselectivity and resolution were obtained on CDMPCZ than CDMPCS.


Subject(s)
Capillary Electrochromatography/instrumentation , Cellulose/analogs & derivatives , Pharmaceutical Preparations/isolation & purification , Phenylcarbamates/chemistry , Zirconium/chemistry , Capillary Electrochromatography/methods , Cellulose/chemistry , Electroosmosis , Stereoisomerism
6.
J Sep Sci ; 30(11): 1672-85, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17623448

ABSTRACT

High temperature liquid chromatography (HTLC) exists in a temperature region beyond ambient (ca. 40 degrees C) and below super critical temperatures. The promises of HTLC, such as increased analysis speed, enhanced separation productivity, "green" LC with pure water mobile phases coupled to universal FID detection, and fast analysis of complex samples by combination with fast 2-D techniques, have become an option for routine practice. The focus of this paper is to review the key developments that have made the application of HTLC a practical technique and draw attention to new developments in 2-D techniques that incorporate HTLC that offer an opportunity to vastly increase the usefulness of HPLC for the analysis of complex samples.

8.
J Chromatogr A ; 1050(2): 151-7, 2004 Oct 01.
Article in English | MEDLINE | ID: mdl-15508307

ABSTRACT

Zirconia is known to be one of the best materials for the chromatographic support due to its excellent chemical, thermal, and mechanical stability. In this work, we report preparation and use of 9-O-(phenyloxycarbonyl)quinine-bonded carbon-clad zirconia (QNCZ) as a chiral stationary phase (CSP) for separation of N-(2,4-dinitrophenyl) (DNP)-amino acids (AAs) enantiomers in reversed-phase liquid chromatography. Retention and enantioselectivity of the QNCZ CSP were compared with those of quinine 3-triethoxysilylpropylcarbamate-coated zirconia (QNZ) and quinine 3-triethoxysilylpropylcarbamate-bonded silica (QNS). The QNCZ CSP showed in general the better enantioselectivity for most of the amino acids studied.


Subject(s)
Amino Acids/isolation & purification , Dinitrobenzenes/isolation & purification , Quinine/analogs & derivatives , Quinine/chemistry , Zirconium/chemistry , Chromatography, High Pressure Liquid , Indicators and Reagents , Silicon Dioxide , Stereoisomerism
9.
J Chromatogr A ; 1002(1-2): 71-8, 2003 Jun 20.
Article in English | MEDLINE | ID: mdl-12885080

ABSTRACT

In this study, 1-microm diameter polybutadiene-encapsulated non-porous zirconia particles were synthesized, slurry packed into 50-microm I.D. fused-silica capillary columns, and evaluated using ultrahigh pressure liquid chromatography. The dependencies of column efficiency and solute retention factor on pressure were investigated. Efficiencies as high as 280000 plates per meter were obtained for the separation of anti-inflammatory drugs at a pressure of 1351 MPa. Comparing the reversed-phase behavior of the polybutadiene-encapsulated non-porous zirconia with octadecylsilane bonded non-porous silica, greater selectivity was found using the zirconia-based material for the applications reported in this study. The encapsulated non-porous zirconia particles demonstrated excellent thermal stability in the separation of polycyclic aromatic hydrocarbons at a temperature of 100 degrees C and a pressure of 1351 MPa.


Subject(s)
Anti-Inflammatory Agents/isolation & purification , Butadienes/chemistry , Chromatography, High Pressure Liquid/methods , Polymers/chemistry , Zirconium/chemistry , Elastomers , Hot Temperature
10.
J Chromatogr B Analyt Technol Biomed Life Sci ; 790(1-2): 143-52, 2003 Jun 25.
Article in English | MEDLINE | ID: mdl-12767327

ABSTRACT

The primary objective of work was to characterize, optimize and model a chromatographic process based on ethylenediamine-N,N,N',N'-tetra(methylphosphonic) acid (EDTPA)-modified zirconia particles. Zirconia particles were produced by spray-drying colloidal zirconia. Zirconia spheres produced were further classified, calcined and modified with EDTPA to yield a solid-phase support for use in bio-chromatography (r_PEZ). Specifically, the ability of r_PEZ to selectively bind and enrich IgG, IgA, and IgM from biological fluids was evaluated and demonstrated. To better understand the force of interaction between the IgG and the r_PEZ, the equilibrium disassociation constant (K(d)) was determined by static binding isotherms, as a function of temperature and by frontal analysis at different linear velocities. The maximum static binding capacity (Q(max)) was found to be in the range 55-65 mg IgG per ml of beads, and unaffected by temperature. The maximum dynamic binding capacity (Q(x)) was found to be in the range 20-12 mg IgG per ml of beads. The adsorption rate constant (k(a)) was determined by a split-peak approach to be between 982 and 3242 l mol(-1) s(-1) depending on the linear velocity. The standard enthalpy and entropy values were estimated for this interaction of IgG with this novel support.


Subject(s)
Chromatography, Liquid/methods , Ethylenediamines/chemistry , Organophosphonates/chemistry , Zirconium/chemistry
11.
J Chromatogr A ; 983(1-2): 83-9, 2003 Jan 03.
Article in English | MEDLINE | ID: mdl-12568372

ABSTRACT

Capillary columns packed with small diameter particles typically lead to low permeability and long separation times in high-performance liquid chromatography. Ultrahigh pressures (>10,000 p.s.i.; 1 p.s.i. is identical with 6,894.76 Pa) can be used to overcome the limitations that small particles impose. Ultrahigh-pressure liquid chromatography (UHPLC) has demonstrated great potential for high-speed and high-efficiency separations. Decreasing the viscosity of the mobile phase by elevating the temperature could additionally reduce the pressure drop and facilitate the use of longer columns or smaller particles to achieve even higher total plate numbers. For this reason, we investigated the use of elevated temperatures in UHPLC. Water-resistant, flexible heater tape covered with insulation was used to provide the desired heat to the column. Polybutadiene-coated 1 microm nonporous zirconia particles were used because of their chemical stability at elevated temperature. A column efficiency as high as 420,000 plates m(-1) was obtained. The effects of temperature and pressure on the separation of parabens were investigated. Separation of five herbicides was completed in 60 s using 26,000 p.s.i. and 90 degrees C.


Subject(s)
Butadienes/chemistry , Chromatography, High Pressure Liquid/methods , Polymers/chemistry , Zirconium/chemistry , Elastomers , Hot Temperature , Stereoisomerism
12.
13.
Int J Aging Hum Dev ; 15(4): 315-21, 1982.
Article in English | MEDLINE | ID: mdl-7183572

ABSTRACT

Intelligence can be defined as the ability to think logically, to conceptualize and abstract from reality. Wisdom can be defined as the ability to grasp human nature, which is paradoxical, contradictory, and subject to continual change. These two constructs hold potential for highlighting positive and adaptive features of development in the later years. both are considered to increase with age, and both provide for life-long acquisition of knowledge. Despite these phenotypic similarities, this paper attempts to illustrate that the nature of wisdom and its function in the developmental process differs sufficiently from cognitive ability to warrant separate scrutiny. These two constructs are compared with respect to the domains of behavior they represent, the operational tasks used to assess them, and the relationship of logic and time in their development. The function of intelligence is characterized as focusing on questions of how to do and accomplish necessary life-supporting tasks; the function of wisdom Is characterized as provoking the individual to consider the consequences of his actions both to self and their effects on others. Wisdom, therefore, evokes questions of should one pursue a particular course of action.


Subject(s)
Aged/psychology , Intelligence , Humans
14.
Int J Aging Hum Dev ; 7(3): 237-45, 1976.
Article in English | MEDLINE | ID: mdl-1002329

ABSTRACT

A study was conducted to examine the role of concrete and formal operations in a young and old population. In addition, the present study explored the relation between operational thought and Cattell's concept of fluid and crystallized intelligence, as well as the role of differential living arrangements in maintaining operational thought. Eighty females from three age groups (18-20 years, 60-70 years and 70-80 years of age) were tested on a series of Piagetian tasks and indices of fluid and crystallized intelligence. The findings supported the notion that age-related performance differences occur in the area of formal operational thought prior to the time they occur in concrete operational thought. Except for the young sample, the operational tasks were found to be unrelated to fluid intelligence at the age levels represented in this study. Living independently as opposed to living in an old age home did not appear to be a significant factor in maintaining operational thought. Discussion focused on the necessity of identifying those factors which influence the developmental course of formal operational thought across the life span.


Subject(s)
Aged , Intelligence , Adolescent , Adult , Female , Homes for the Aged , Humans , Task Performance and Analysis , Time Factors
16.
J Gerontol ; 30(1): 53-5, 1975 Jan.
Article in English | MEDLINE | ID: mdl-1109393

ABSTRACT

The theory of fluid and crystallized intelligence predicts that the relationship between these two abilities will decline systematically across the age span after young adulthood. In order to test this hypothesis in an elderly sample, the Raven Progressive Martices and the WAIS vocabulary subtest were administered to a sample of individuals (N=40), ranging in age from 60 to 79, and also, for purposes of comparison, to a sample of young adults (N=35). It was found that the correlation was significantly lower in the elderly sample (.386) than in the young adult sample (.672).


Subject(s)
Aging , Intelligence , Adult , Aged , Female , Humans , Intelligence Tests , Middle Aged , Problem Solving , Statistics as Topic , Verbal Learning
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