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1.
Res Social Adm Pharm ; 13(3): 485-493, 2017.
Article in English | MEDLINE | ID: mdl-27514236

ABSTRACT

OBJECTIVE: Depression screening should be increased when prevailing knowledge underscoring medication-associated mental health risk is highest. Depression screening in primary care practices when medications with mental health risk were prescribed was estimated while considering the absence and presence of clinical decision support systems. MATERIALS AND METHODS: A cross-sectional, descriptive study using the National Ambulatory Medical Care Survey (NAMCS) data from 2008 to 2010 was conducted. Primary care physician visits were classified based on whether a medication prescribed had a contraindication, severe warning, moderate warning, adverse event only, or no documented mental health risk. Adjusted odds of depression screening for each risk warning level were estimated while controlling for important sociodemographic factors and presence of computerized systems for medication warnings and guideline recommendations. RESULTS: Depression screening at primary care practice visits when medications were prescribed was 2.1% and increased to 2.8% or higher when medications had a moderate or severe mental health risk warning or medication-disease contraindication. Depression screening was increased at visits when at least one medication was prescribed that had a contraindication (AOR = 6.31, P < 0.001), severe warning (AOR = 2.04, P = 0.003), or moderate warning (AOR = 2.50, P = 0.012) for mental health risk, but not for mental health adverse event only warnings alone (AOR = 1.54, P = 0.074). DISCUSSION: Depression screening is increased when medications were prescribed with a documented mental health risk. Presence of clinical decision support systems may help discern between minor and major medication-associated mental health risks. CONCLUSIONS: Appropriately, positioned warning systems with targeted content, workflow redesign, and health information exchange may improve depression screening in at-risk patients.


Subject(s)
Decision Support Systems, Clinical , Depression/diagnosis , Mass Screening/methods , Practice Patterns, Physicians'/statistics & numerical data , Adolescent , Adult , Aged , Contraindications , Cross-Sectional Studies , Female , Health Care Surveys , Health Information Exchange , Humans , Male , Middle Aged , Practice Guidelines as Topic , Prescription Drugs/administration & dosage , Prescription Drugs/adverse effects , Primary Health Care/organization & administration , Primary Health Care/statistics & numerical data , Risk , Workflow , Young Adult
2.
J Biol Chem ; 285(43): 32860-32868, 2010 Oct 22.
Article in English | MEDLINE | ID: mdl-20724473

ABSTRACT

The activation of leukocyte function-associated antigen-1 (LFA-1) plays a critical role in regulating immune responses. The metal ion-dependent adhesion site on the I-domain of LFA-1 α(L) subunit is the key recognition site for ligand binding. Upon activation, conformation changes in the I-domain can lead LFA-1 from the low affinity state to the high affinity (HA) state. Using the purified HA I-domain locked by disulfide bonds for immunization, we developed an mAb, 2E8, that specifically binds to cells expressing the HA LFA-1. The surface plasmon resonance analysis has shown that 2E8 only binds to the HA I-domain and that the dissociation constant (K(D)) for HA I-domain is 197 nm. The binding of 2E8 to the HA I-domain is metal ion-dependent, and the affinity decreased as Mn(2+) was replaced sequentially by Mg(2+) and Ca(2+). Surface plasmon resonance analysis demonstrates that 2E8 inhibits the interaction of HA I-domain and ICAM-1. Furthermore, we found that 2E8 can detect activated LFA-1 on both JY and Jurkat cells using flow cytometry and parallel plate adhesion assay. In addition, 2E8 inhibits JY cell adhesion to human umbilical vein endothelial cells and homotypic aggregation. 2E8 treatment reduces the proliferation of both human CD4(+) and CD8(+) T cells upon OKT3 stimulation without the impairment of their cytolytic function. Taken together, these data demonstrate that 2E8 is specific for the high affinity form of LFA-1 and that 2E8 inhibits LFA-1/ICAM-1 interactions. As a novel activation-specific monoclonal antibody, 2E8 is a potentially useful reagent for blocking high affinity LFA-1 and modulating T cell activation in research and therapeutics.


Subject(s)
Antibodies, Monoclonal/pharmacology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Intercellular Adhesion Molecule-1/immunology , Lymphocyte Function-Associated Antigen-1/immunology , Metals/immunology , Animals , Antibodies, Monoclonal/immunology , CD4-Positive T-Lymphocytes/cytology , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/metabolism , Cations, Divalent/immunology , Cations, Divalent/metabolism , Cell Adhesion/drug effects , Cell Adhesion/immunology , Disulfides/immunology , Disulfides/metabolism , Endothelial Cells/cytology , Endothelial Cells/immunology , Endothelial Cells/metabolism , Flow Cytometry , Gene Expression Regulation/drug effects , Gene Expression Regulation/immunology , Humans , Immunity, Cellular/drug effects , Immunity, Cellular/immunology , Intercellular Adhesion Molecule-1/metabolism , Jurkat Cells , K562 Cells , Lymphocyte Activation/drug effects , Lymphocyte Activation/immunology , Lymphocyte Function-Associated Antigen-1/metabolism , Metals/metabolism , Mice , Mice, Inbred BALB C , Muromonab-CD3/immunology , Muromonab-CD3/metabolism , Protein Structure, Tertiary , Protein Subunits/immunology , Protein Subunits/metabolism , Surface Plasmon Resonance/methods , Umbilical Veins/cytology , Umbilical Veins/immunology
3.
J Biol Chem ; 284(19): 12645-53, 2009 May 08.
Article in English | MEDLINE | ID: mdl-19297325

ABSTRACT

The activation of LFA-1 (lymphocyte function-associated antigen) is a critical event for T cell co-stimulation. The mechanism of LFA-1 activation involves both affinity and avidity regulation, but the role of each in T cell activation remains unclear. We have identified antibodies that recognize and block different affinity states of the mouse LFA-1 I-domain. Monoclonal antibody 2D7 preferentially binds to the low affinity conformation, and this specific binding is abolished when LFA-1 is locked in the high affinity conformation. In contrast, M17/4 can bind both the locked high and low affinity forms of LFA-1. Although both 2D7 and M17/4 are blocking antibodies, 2D7 is significantly less potent than M17/4 in blocking LFA-1-mediated adhesion; thus, blocking high affinity LFA-1 is critical for preventing LFA-1-mediated adhesion. Using these reagents, we investigated whether LFA-1 affinity regulation affects T cell activation. We found that blocking high affinity LFA-1 prevents interleukin-2 production and T cell proliferation, demonstrated by TCR cross-linking and antigen-specific stimulation. Furthermore, there is a differential requirement of high affinity LFA-1 in the activation of CD4(+) and CD8(+) T cells. Although CD4(+) T cell activation depends on both high and low affinity LFA-1, only high affinity LFA-1 provides co-stimulation for CD8(+) T cell activation. Together, our data demonstrated that the I-domain of LFA-1 changes to the high affinity state in primary T cells, and high affinity LFA-1 is critical for facilitating T cell activation. This implicates LFA-1 activation as a novel regulatory mechanism for the modulation of T cell activation and proliferation.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Lymphocyte Activation/physiology , Lymphocyte Function-Associated Antigen-1/physiology , Animals , Antibodies, Blocking/immunology , Antibodies, Monoclonal/immunology , Antibody Affinity/immunology , Cell Adhesion , Flow Cytometry , Interleukin-2/metabolism , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Transgenic , Receptors, Antigen, T-Cell/physiology
4.
J Biol Chem ; 283(16): 10642-8, 2008 Apr 18.
Article in English | MEDLINE | ID: mdl-18199751

ABSTRACT

MEM83 is an inserted domain (I-domain)-specific antibody that up-regulates the interaction of LFA-1 with ICAM-1 through an outside-in activation mechanism. We demonstrate here that there is no change in the affinity of the MEM83 antibody for the I-domain in either its low (wild-type) or high affinity form and that MEM83 does not enhance the binding of the wild-type I-domain to ICAM-1. Furthermore, we show that the antibody acts as an activating agent to induce LFA-1/ICAM-1-dependent homotypic cell aggregation only as an IgG, but not as a Fab fragment. On the basis of these data, we propose an avidity-based mechanism that requires no direct activation of the LFA-1 I-domain by the binding of the antibody; rather, activation is enhanced when there is an interaction with both arms of the IgG. A molecular model of the antibody interaction with LFA-1 illustrates the symmetry and accessibility of the two MEM83 epitopes across the LFA-1/ICAM-1 heterotetramer. We hypothesize that MEM83 stabilizes adjacent LFA-1 molecules in their active form by the free energy that is gained from the binding of the I-domains to each arm of the IgG. This leads to stabilization of the open state of the integrin and outside-in signaling. Our model supports a mechanism in which both affinity and avidity regulation are required in the activation of LFA-1.


Subject(s)
Lymphocyte Function-Associated Antigen-1/metabolism , Antibodies, Monoclonal/chemistry , Cell Line , Humans , Immunoglobulin G/chemistry , Intercellular Adhesion Molecule-1/metabolism , Kinetics , Models, Biological , Models, Molecular , Molecular Conformation , Protein Binding , Protein Conformation , Protein Structure, Tertiary , Surface Plasmon Resonance , Thermodynamics
5.
Planta Med ; 72(4): 383-6, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16557484

ABSTRACT

One new and one known isoflavan, 3 S(+)-7-methoxymanuifolin K (1) and manuifolin K (2), respectively, were isolated from methanolic extracts of Dalea aurea (Fabaceae). Isoflavans 1 and 2 exhibited significant in vitro activity against the ameba Naegleria fowleri, an organism responsible for an infrequent but rapidly fatal form of primary amebic meningoencephalitis (PAM). At concentrations of 30 microM, both 1 and 2 caused growth inhibition of N. fowleri at a level comparable to amphotericin B (at 0.1 microM), the currently preferred treatment for this disease. Over a seven-day growth period, 1 and 2 (30 microM) exhibited superior growth inhibition of N. fowleri than amphotericin B after day 4. Isoflavan 2 was evaluated in a mouse model of PAM at a dose of 25 mg/kg/day for five days. While amphotericin B (2.5 mg/kg/day) offered 12.5 % protection of the mice, compound 2 did not protect the mice from PAM infection compared to controls.


Subject(s)
Amebicides/pharmacology , Amoeba/drug effects , Central Nervous System Protozoal Infections/drug therapy , Fabaceae , Phytotherapy , Plant Extracts/pharmacology , Amebicides/administration & dosage , Amebicides/therapeutic use , Animals , Disease Models, Animal , Isoflavones/administration & dosage , Isoflavones/pharmacology , Isoflavones/therapeutic use , Male , Meningoencephalitis/drug therapy , Mice , Mice, Inbred Strains , Opportunistic Infections/drug therapy , Parasitic Sensitivity Tests , Plant Extracts/administration & dosage , Plant Extracts/therapeutic use
6.
J Nat Prod ; 69(2): 261-4, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16499327

ABSTRACT

Two new 2-arylbenzofuran aldehydes (1 and 2) and three known phenolic compounds (3-5) were isolated from organic extracts of Dalea spinosa. These compounds were evaluated for their intrinsic antimicrobial activity and their ability to perform as multidrug-resistance inhibitors by potentiating the activity of known antimicrobials against a variety of pathogenic microorganisms. Compound 1 and its acetate derivative 6 exhibited no direct antimicrobial activity but enhanced the effect of the weak plant antimicrobial berberine when tested against Staphylococcus aureus. Additional potentiation assays with S. aureus overexpression and knockout isogenic efflux mutants for the NorA pump were done in order to assess whether the potentiating effects were associated with inhibition of this known pump mechanism.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Benzofurans/isolation & purification , Benzofurans/pharmacology , Fabaceae/chemistry , Plants, Medicinal/chemistry , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/chemistry , Benzofurans/chemistry , Berberine/pharmacology , Desert Climate , Drug Resistance, Multiple , Microbial Sensitivity Tests , Molecular Structure , Staphylococcus aureus/genetics
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