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1.
Clin Nurs Res ; 30(6): 911-920, 2021 07.
Article in English | MEDLINE | ID: mdl-33736482

ABSTRACT

Hip fractures decrease older adults' physical activity and quality of life (QoL). However, no current self-efficacy care programs are managed by clinical nurses, and thus no studies have measured their effects on self-care self-efficacy (SCSE). Hence, this quasi-experimental study determined the effectiveness of a self-efficacy care program (SECP) in 104 older adults receiving hip-fracture surgery who were divided into intervention and control groups. The Strategies Used by People to Promote Health and Short Form-36 were administered pre-surgery and at 1 and 3-month intervals post-surgery. The SCSE and QoL of the SECP group were significantly better than the control group at 1- and 3-month follow-ups post-surgery. Both groups' QoL decreased at one-month post-surgery but increased by 3-months post-surgery. The SECP group had higher psychological QoL than the control group post-surgery. This intervention increased the SCSE and QoL of older adults with hip fractures and improved post-operative care.


Subject(s)
Hip Fractures , Quality of Life , Aged , Health Promotion , Hip Fractures/surgery , Humans , Self Care , Self Efficacy
2.
Acta Biomater ; 114: 183-192, 2020 09 15.
Article in English | MEDLINE | ID: mdl-32688089

ABSTRACT

Atopic dermatitis (AD), a common, relapsing, inflammatory disorder of the skin, is associated with T helper type 2 (Th2)-biased immune responses. Despite the efficacy of existing drugs for AD treatment, their safety and side effects cause concern. The present study describes the use of dissolvable poly-γ-glutamate (γ-PGA) microneedles (MNs) with immunomodulatory effects for effectively relieving AD-like symptoms in Nc/Nga mice. γ-PGA MNs can easily penetrate the epidermis and release γ-PGA into the dendritic cell-rich dermis to interact with dendritic cells for modulating immune responses. Transdermal administration of high-molecular-weight (HMW, 1100 kDa) γ-PGA MNs significantly reduced clinical dermatitis scores, epidermal thickness, and mast cell infiltration in mice by downregulating immunoglobulin (Ig)E and IgG1 levels (Th2-associated antibodies) compared with the AD control group. However, low-molecular-weight (200-400 kDa) γ-PGA MNs ameliorated AD-like skin lesions less effectively than HMW γ-PGA MNs, thus indicating that the MW of γ-PGA may affect its immunomodulatory properties. Notably, the mouse skin quickly recovered its barrier function within 4 h after MN application. No weight loss or abnormality was observed in the MN-treated mice during the 8-week treatment period. These results suggest that the γ-PGA MNs represent an innovative, safe, and reliable therapeutic strategy for AD management. STATEMENT OF SIGNIFICANCE: This study is the first to explore the feasibility of using poly-γ-glutamate (γ-PGA) microneedles (MNs) as transdermal immunomodulators for improving atopic dermatitis (AD) symptoms and to evaluate their immunomodulatory effect in mice with spontaneously developed AD. Transdermal administration of γ-PGA MNs enables the γ-PGA to localize in the skin for activation of dermal dendritic cells, thus modulating immune responses. We demonstrate that high-molecular-weight γ-PGA MNs can be retained in the skin for at least 6 days and effectively suppress AD-like skin lesions in mice by reducing infiltration of mast cells and downregulating Th2-associated antibody production (IgE and IgG1). The developed MN device has the potential to replace conventional therapy and to become an innovative treatment strategy for AD.


Subject(s)
Dermatitis, Atopic , Administration, Cutaneous , Animals , Cytokines , Dermatitis, Atopic/drug therapy , Immunologic Factors/therapeutic use , Mice , Polyglutamic Acid/analogs & derivatives , Skin
3.
Proteins ; 85(10): 1831-1844, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28614901

ABSTRACT

The ability of LuxR-type proteins to regulate transcription is controlled by bacterial pheromones, N-acylhomoserine lactones (AHLs). Most LuxR-family proteins require their cognate AHLs for activity, and some of them require AHLs for folding and stability, and for protease-resistance. However, a few members of this family are able to fold, dimerize, bind DNA, and regulate transcription in the absence of AHLs; moreover, these proteins are antagonized by their cognate AHLs. One such protein is YenR of Yersinia enterocolitica, which is antagonized by N-3-oxohexanoyl-l-homoserine lactone (OHHL). This pheromone is produced by the OHHL synthase, a product of the adjacent yenI gene. Another example is CepR2 of Burkholderia cenocepacia, which is antagonized by N-octanoyl-l-homoserine lactone (OHL), whose synthesis is directed by the cepI gene of the same bacterium. Here, we describe the high-resolution crystal structures of the AHL binding domains of YenR and CepR2. YenR was crystallized in the presence and absence of OHHL. While this ligand does not cause large scale changes in the YenR structure, it does alter the orientation of several highly conserved YenR residues within and near the pheromone-binding pocket, which in turn caused a significant movement of a surface-exposed loop.


Subject(s)
Bacterial Proteins/chemistry , Homoserine/analogs & derivatives , Lactones/chemistry , Trans-Activators/chemistry , Bacterial Proteins/genetics , Burkholderia cenocepacia/chemistry , Crystallography, X-Ray , DNA-Binding Proteins/chemistry , Gene Expression Regulation, Bacterial , Homoserine/chemistry , Pheromones/chemistry , Protein Conformation , Protein Domains/genetics , Protein Folding , Trans-Activators/genetics , Transcription Factors/chemistry , Yersinia enterocolitica/chemistry
4.
J Bacteriol ; 193(19): 5442-9, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21804007

ABSTRACT

OccR is a LysR-type transcriptional regulator of Agrobacterium tumefaciens that positively regulates the octopine catabolism operon of the Ti plasmid. Positive control of the occ genes occurs in response to octopine, a nutrient released from crown gall tumors. OccR also functions as an autorepressor in the presence or absence of octopine. OccR binds to a site between occQ and occR in the presence or absence of octopine, although octopine triggers a conformational change that shortens the DNA footprint and relaxes a DNA bend. In order to determine the roles of this conformational change in transcriptional activation, we isolated 11 OccR mutants that were defective in activation of the occQ promoter but were still capable of autorepression. The mutations in these mutants spanned most of the length of the protein. Two additional positive-control mutants were isolated using site-directed mutagenesis. Twelve mutant proteins displayed a high-angle DNA bend in the presence or absence of octopine. One mutant, the L26A mutant, showed ligand-responsive DNA binding similar to that of wild-type OccR and therefore must be impaired in a subsequent step in activation.


Subject(s)
Agrobacterium tumefaciens/metabolism , Bacterial Proteins/metabolism , DNA-Binding Proteins/metabolism , Transcription Factors/metabolism , Agrobacterium tumefaciens/drug effects , Agrobacterium tumefaciens/genetics , Arginine/analogs & derivatives , Arginine/pharmacology , Bacterial Proteins/genetics , Carrier Proteins/genetics , Carrier Proteins/metabolism , DNA-Binding Proteins/genetics , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mutagenesis, Site-Directed , Mutation , Promoter Regions, Genetic/genetics , Transcription Factors/genetics
5.
J Biol Chem ; 283(12): 7616-27, 2008 Mar 21.
Article in English | MEDLINE | ID: mdl-18184652

ABSTRACT

Malignant breast cancer cells that have entered the blood circulation from primary mammary fat pad tumors or are grown in end-over-end suspension culture assemble a characteristic, multi-globular polymeric fibronectin (polyFn) coat on their surfaces. Surface polyFn is critical for pulmonary metastasis, presumably by facilitating lung vascular arrest via endothelial dipeptidylpeptidase IV (CD26). Here, we show that cell-surface polyFn assembly is initiated by the state of suspension, is dependent upon the synthesis and secretion of cellular Fn, and is augmented in a dose- and time-dependent manner by plasma Fn. PolyFn assembly is regulated by protein kinase Cepsilon (PKCepsilon), which translocates rapidly and in increasing amounts from the cytosol to the plasma membrane and is phosphorylated. PolyFn assembly is impeded by select inhibitors of this kinase, i.e. bisindolylmaleimide I, Ro-32-0432, Gö6983, and Rottlerin, by the phorbol 12-myristate 13-acetate-mediated and time-dependent loss of PKCepsilon protein and decreased plasma membrane translocation, and more specifically, by stable transfection of lung-metastatic MTF7L breast cancer cells with small interfering RNA-PKCepsilon and dominant-negative PKCepsilon constructs (e.g. RD-PKCepsilon). The inability to assemble a cell surface-associated polyFn coat by knockdown of endogenous Fn or PKCepsilon impedes cancer cells from metastasis to the lungs. The present studies identify a novel regulatory mechanism for polyFn assembly on blood-borne breast cancer cells and depict its effect on pulmonary metastasis.


Subject(s)
Fibronectins/metabolism , Lung Neoplasms/enzymology , Mammary Neoplasms, Animal/enzymology , Neoplasm Proteins/metabolism , Neoplastic Cells, Circulating/metabolism , Protein Kinase C-epsilon/metabolism , Animals , Cell Membrane/enzymology , Cell Membrane/metabolism , Dipeptidyl Peptidase 4/genetics , Dipeptidyl Peptidase 4/metabolism , Female , Fibronectins/genetics , Lung Neoplasms/genetics , Lung Neoplasms/secondary , Mammary Neoplasms, Animal/genetics , Neoplasm Proteins/genetics , Protein Kinase C-epsilon/antagonists & inhibitors , Protein Kinase C-epsilon/genetics , Protein Kinase Inhibitors/pharmacology , Protein Transport/drug effects , Protein Transport/genetics , Rats , Rats, Inbred F344
6.
Vaccine ; 26(2): 277-87, 2008 Jan 10.
Article in English | MEDLINE | ID: mdl-18055070

ABSTRACT

We demonstrated earlier that immunization with recombinant Leptospira immunoglobulin like protein A (LigA) induced significant protection against virulent Leptospira interrogans serovar Pomona challenge in hamsters. However, the protective immune mechanism remains unclear. In the present study we demonstrated the protective efficacy of a LigA DNA vaccine and evaluated the immune mechanism underlying the protection against leptospirosis in hamsters. The LigA DNA vaccine was constructed in two truncated forms as the conserved portion (LigAcon) and a variable portion (LigAvar). Four-week-old hamsters were immunized three times at two-week intervals with vector alone or an equal amount of a recombinant construct containing either LigAcon or LigAvar. All animals were challenged intraperitoneally 2 weeks after the last immunization with a dose (LD50=10(8)) of virulent L. interrogans serovar Pomona. Prior to challenge, four animals were sacrificed, the spleen was removed aseptically, and splenocytes were assayed for lymphocyte proliferation and cytokine profiles in response to recall antigen. The protective efficacy was evaluated on the basis of survival and histopathological lesions in the kidney. The immuno-protective mechanism was assessed on the basis of Th1/Th2 profile of cytokines in immunized animals. Our results indicate that immunization with LigA DNA vaccine provides significant protection against leptospirosis. We suggest that immuno-protection is conferred by both humoral and cellular immunity as revealed by an increase in antibody titers during subsequent boosters, significant proliferation of lymphocytes and enhancement of both Th1 and Th2 cytokines. Taken together, the present study suggests that a LigA DNA vaccine is a promising candidate for prevention of leptospirosis.


Subject(s)
Antigens, Bacterial/immunology , Leptospira interrogans serovar pomona/immunology , Leptospirosis/prevention & control , Vaccines, DNA/immunology , Animals , Antibodies, Bacterial/blood , Antigens, Bacterial/genetics , Cell Proliferation , Cricetinae , Cytokines/biosynthesis , Cytokines/immunology , Female , Immunization, Secondary , Kidney/pathology , Leptospirosis/immunology , Lymphocytes/immunology , Spleen/immunology , Survival Analysis , Vaccines, DNA/genetics
7.
Vaccine ; 25(48): 8190-7, 2007 Nov 23.
Article in English | MEDLINE | ID: mdl-17936448

ABSTRACT

Leptospiral putative outer membrane proteins (OMPs) are likely to be essential components of more effective vaccines. Recently completed genomic sequences of Leptospira allowed us to target putative OMPs for the development of recombinant vaccines. We focused on 12 putative OMPs that had no homology with other organisms listed in the NCBI database except MceI and MceII of Leptospira, which are approximately 25% homologous to MceI of Mycobacterium tuberculosis. All putative OMPs were cloned, expressed and purified as glutathione-S-transferase (GST) fusion proteins. Primary screening for immunoprotective potential was performed in hamsters challenged with an LD50 inoculum of low passage serovar Pomona. Out of these 12 OMPs three fusion proteins viz. rLp1454, rLp1118 and rMceII were found to be protective in a hamster model of leptospirosis. The protective efficacy was evaluated on the basis of survival, histopathological lesions in vital organs and antibody responses against each antigen. All the recombinant proteins were able to enhance the survival and reduce the histopathological lesions. In contrast, control animals immunized with rGST demonstrated low survival and had significant lesions. Further, these three proteins were evaluated for synergistic protective efficacy as compared to LigA, which has already been established as a protective antigen. Our results indicate that rLp1454, rLp1118, and rMceII showed protection individually and synergistically against serovar Pomona infection, which may help us to develop a multicomponent vaccine for leptospirosis.


Subject(s)
Antigens, Bacterial/administration & dosage , Bacterial Outer Membrane Proteins/immunology , Bacterial Vaccines/immunology , Leptospira/immunology , Leptospirosis/prevention & control , Animals , Antigens, Bacterial/immunology , Bacterial Outer Membrane Proteins/administration & dosage , Cricetinae , Disease Models, Animal , Leptospirosis/immunology , Lethal Dose 50 , Recombinant Fusion Proteins/immunology
8.
Infect Immun ; 74(3): 1745-50, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16495547

ABSTRACT

We previously reported the cloning and characterization of leptospiral immunoglobulin-like proteins LigA and LigB of Leptospira interrogans. LigA and LigB are conserved at the amino-terminal region but are variable at the carboxyl-terminal region. Here, we evaluate the potential of recombinant LigA (rLigA) as a vaccine candidate against infection by L. interrogans serovar Pomona in a hamster model. rLigA was truncated into conserved (rLigAcon) and variable (rLigAvar) regions and expressed in Escherichia coli as a fusion protein with glutathione-S-transferase (rLigA). Golden Syrian hamsters were immunized at 3 and 6 weeks of age with rLigA (rLigAcon and rLigAvar) with aluminum hydroxide as an adjuvant. Hamsters given recombinant glutathione-S-transferase (rGST)-adjuvant and phosphate-buffered saline-adjuvant served as nonvaccinated controls. Three weeks after the last vaccination, all animals were challenged intraperitoneally with 10(8) L. interrogans serovar Pomona bacteria (NVSL 1427-35-093002). All hamsters immunized with recombinant LigA survived after challenge and had no significant histopathological changes. In contrast, nonimmunized and rGST-immunized hamsters were subjected to lethal doses, and the hamsters that survived showed severe tubulointerstitial nephritis. All vaccinated animals showed a rise in antibody titers against rLigA. Results from this study indicate that rLigA is a potential vaccine candidate against L. interrogans serovar Pomona infection.


Subject(s)
Antigens, Bacterial/administration & dosage , Leptospira interrogans serovar pomona/immunology , Leptospirosis/prevention & control , Staphylococcal Protein A/immunology , Adjuvants, Immunologic , Animals , Antigens, Bacterial/immunology , Cricetinae , Disease Models, Animal , Immunoglobulins , Kidney/cytology , Leptospirosis/immunology , Recombinant Proteins/administration & dosage , Recombinant Proteins/immunology , Vaccines, Synthetic
9.
FEMS Microbiol Lett ; 243(2): 339-45, 2005 Feb 15.
Article in English | MEDLINE | ID: mdl-15686833

ABSTRACT

We report the expression and characterization of the omp52 gene of Leptospira santarosai serovar Shermani strain CCF that is isolated in Taiwan. omp52 was identified among pathogenic leptospires but not among non-pathogenic leptospires by using suppression subtractive hybridization in our previous study. With an open reading frame of 1371 bp that encodes 456 amino acids and a predicted molecular mass of 52.6 kDa, Omp52 was shown to be an outer membrane protein containing a C-terminal OmpA consensus domain and exposed on the cell surface. Furthermore, Omp52 increases dramatically during the stationary phase, indicating that the expression of Omp52 is environmentally regulated. By using immunoblotting analysis, we proved that Omp52 was expressed in human patients infected with leptospires. These observations suggest that Omp52 may play roles in the interaction of host cells and pathogens during infection.


Subject(s)
Bacterial Outer Membrane Proteins/genetics , Bacterial Outer Membrane Proteins/metabolism , Gene Expression Regulation, Bacterial , Leptospira/growth & development , Amino Acid Sequence , Bacterial Outer Membrane Proteins/immunology , Humans , Immune Sera/immunology , Leptospira/genetics , Leptospira/immunology , Leptospira/metabolism , Leptospirosis/immunology , Leptospirosis/microbiology , Molecular Sequence Data , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Analysis, DNA
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