Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 52
Filter
1.
Vision Res ; 201: 108119, 2022 12.
Article in English | MEDLINE | ID: mdl-36108416

ABSTRACT

The current study examined the relationships among temporal processing speed, spatial visual span and Chinese character reading speed in normal central and peripheral vision. Maximum reading speed (MRS) and critical print size (CPS) of 26 native Chinese readers (13 young and 13 older adults) were determined at three visual field locations: central vision, 10° left and 10° below fixation using a rapid serial visual presentation (RSVP) task. Temporal processing speed was measured using trigrams of randomly selected Chinese characters presented at a range of exposure durations, while spatial visual span was measured using trigrams presented at different spatial positions. It was found that shorter temporal processing speed and larger spatial visual span were associated with faster MRS at the central and inferior visual field locations, but not at the left of fixation location. As expected, reading and visual span metrics were better in central vision compared to both peripheral locations. In addition, reading, temporal processing, and spatial visual span metrics were better in the young than older subjects (except for similar temporal processing speed at two peripheral locations). The results for central and inferior presentation locations support the hypothesis that temporal processing speed and spatial visual span were associated with Chinese character reading speed. Surprisingly, no correlation was observed for the 10° left of the fixation location, suggesting that the factors affecting reading speed might differ for inferior and lateral peripheral viewing locations.


Subject(s)
Reading , Visual Field Tests , Humans , Aged , Psychophysics , Vision, Ocular , China
2.
J Cancer Educ ; 37(1): 169-178, 2022 02.
Article in English | MEDLINE | ID: mdl-32564251

ABSTRACT

There are several treatment options for localized prostate cancer with very similar outcome but vary in terms of technique and side effect profiles and risks. Considering the potential difficulty in choosing the best treatment, a patient decision aid (PDA) is used to help patients in their decision-making process. However, the use and applicability of PDA in a country in Asia Pacific region like Malaysia is still unknown. This study aims to evaluate the effectiveness of a PDA modified to the local context in improving patients' knowledge, decisional conflict, and preparation for decision making among men with localized prostate cancer. Sixty patients with localized prostate cancer were randomly assigned to control and intervention groups. A self-administered questionnaire, which evaluate the knowledge on prostate cancer (23 items), decisional conflict (10 items) and preparation for decision-making (10 items), was given to all participants at pre- and post-intervention. Data were analyzed using independent T test and paired T test. The intervention group showed significant improvement in knowledge (p = 0.02) and decisional conflict (p = 0.01) from baseline. However, when compared between the control and intervention groups, there were no significant differences at baseline and post-intervention on knowledge, decisional conflict and preparation for decision-making. A PDA on treatment options of localized prostate cancer modified to the local context in an Asia Pacific country improved patients' knowledge and decisional conflict but did not have significant impact on the preparation for decision-making. The study was also registered under the Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12614000668606 registered on 25/06/2014.


Subject(s)
Decision Support Techniques , Prostatic Neoplasms , Australia , Decision Making , Humans , Male , Patient Participation , Prostatic Neoplasms/therapy , Tertiary Care Centers
3.
BMC Public Health ; 21(1): 1186, 2021 06 22.
Article in English | MEDLINE | ID: mdl-34158013

ABSTRACT

BACKGROUND: Limited health literacy among people with asthma is associated with poor adherence to self-management activities, thus poor clinical outcomes. This study aimed to determine the prevalence of health literacy level and its determinants among people with asthma in the Malaysian primary healthcare settings. METHOD: A cross-sectional study was conducted among participants aged > 18 years with asthma who attended five primary health clinics in Malaysia. Systematic random sampling was employed with a final sample of 550 participants. The questionnaires included the validated Malay version of Health Literacy Scale (HLS) and asthma control questionnaire (ACQ). Statistical analysis was done using SPSS version 25. Multiple logistic regression was performed to determine the determinants for limited health literacy. RESULTS: The participants mean age of the participants was 48 (SD15.4) years. Most of the participants were women (64%) and of Malay ethnicity (51.1%). Nearly half had a secondary level of education, n = 112, (45.8%). Mean duration of asthma diagnosis is 20.6 (SD 15.9) years. More than half (62.5%) had a family history of asthma. About half (50.9%) had uncontrolled asthma, with 87.3% self-rated themselves as having controlled asthma. About a third (29.1%) received education on of asthma action plan, but only 7.1% of these owned a written version an asthma action plan. Limited health literacy accounts for 60.5% of the participants. The significant determinants for limited health literacy included lower educational attainment (p < 0.001), family history of asthma (p = 0.034), < 20 years duration of asthma diagnosis (p = 0.031) and not receiving asthma action plan education (p < 0.001). CONCLUSION: In this study population, more than half of the people living with asthma were found to have limited health literacy, which was associated with not having received self-management education supported by an asthma action plan. Future interventions should include strategies that ensure they meet the needs of people with limited health literacy.


Subject(s)
Asthma , Health Literacy , Adolescent , Asthma/epidemiology , Cross-Sectional Studies , Female , Humans , Malaysia/epidemiology , Primary Health Care , Surveys and Questionnaires
4.
Gastric Cancer ; 23(5): 824-836, 2020 09.
Article in English | MEDLINE | ID: mdl-32239298

ABSTRACT

BACKGROUND: The effects of cancer-associated fibroblasts (CAF) on the progression of gastric carcinoma (GC) has recently been demonstrated. However, agents targeting the interaction between CAF and GC cells have not been applied in a clinical setting. Here, we examined if inhibition for Axl receptor tyrosine kinase (AXL) can suppress CAF-induced aggressive phenotype in GC. METHODS: We investigated the function of CAF-derived growth arrest-specific 6 (GAS6), a major ligand of AXL, on the migration and proliferation of GC cells. The effect of the AXL inhibitor, BGB324, on the CAF-induced aggressive phenotype of GC cells was also investigated. In addition, we performed immunohistochemistry to examine the expression of phosphorylated AXL protein in 175 GC tissues and evaluated its correlation with the prognosis. RESULTS: The qPCR and western blot analysis showed that GAS6 expression was higher in CAF relative to other cells. We found that co-culture with CAF increased the phosphorylation of AXL (P-AXL), differentiation into a mesenchymal-like phenotype, and cell survival in GC cell lines. When the expression of AXL was genetically inhibited in GC cells, the effect of CAF was reduced. BGB324, a small molecule inhibitor of AXL, suppressed the effects of CAF on GC cell lines. In GC tissues, high levels of P-AXL were significantly associated with poor overall survival (P = 0.022). CONCLUSIONS: We concluded that CAF are a major source of GAS6 and that GAS6 promotes an aggressiveness through AXL activation in GC. We suggested that an AXL inhibitor may be a novel agent for GC treatment.


Subject(s)
Benzocycloheptenes/pharmacology , Cancer-Associated Fibroblasts/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Intercellular Signaling Peptides and Proteins/chemistry , Proto-Oncogene Proteins/antagonists & inhibitors , Receptor Protein-Tyrosine Kinases/antagonists & inhibitors , Stomach Neoplasms/drug therapy , Triazoles/pharmacology , Biomarkers, Tumor , Cancer-Associated Fibroblasts/metabolism , Cancer-Associated Fibroblasts/pathology , Cell Proliferation , Cell Survival , Disease Progression , Humans , Phosphorylation , Prognosis , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Survival Rate , Tumor Cells, Cultured , Axl Receptor Tyrosine Kinase
5.
PLoS One ; 14(9): e0222587, 2019.
Article in English | MEDLINE | ID: mdl-31560696

ABSTRACT

Adipose-derived mesenchymal stem cells (AdMSCs) have been reported to ameliorate neurological deficits after acute ischemic stroke. As neuregulin 1 (NRG1, or heregulin 1), a growth factor with versatile functions in the central nervous system, has demonstrated protective effects against ischemic brain injuries, we have generated NRG1-overexpressing AdMSCs in order to investigate whether NRG1-AdMSCs could enhance therapeutic benefits of AdMSCs in ischemic stroke. After AdMSCs were infected with adenoviral NRG1, increased NRG1 secretion in NRG1-AdMSCs was confirmed with ELISA. At 1 d after ischemic stroke that was induced by the occlusion of middle cerebral artery (MCAo) for 60 min in Sprague Dawley (SD) rats, adenoviral NRG1, AdMSCs, NRG1-AdMSCs, or PBS were injected into the striatum and serial neurologic examinations were performed. Administration of NRG1-AdMSCs resulted in significant improvement of functional outcome following stroke compared to AdMSCs- or adenoviral NRG1-treated group, in addition to the reduction in the infarct size evaluated by hematoxylin and eosin staining. When NRG1 expression in the brain was examined by double immunofluorescence to human nuclei (HuNu)/NRG1 and ELISA, NRG1-AdMSCs demonstrated marked increase in NRG1 expression. Moreover, western blot analysis further showed that transplantation of NRG1-AdMSCs significantly increased both endogenous and adenoviral NRG1 expression compared to AdMSCs-treated group. To elucidate molecular mechanisms, NRG1-associated downstream molecules were evaluated by western blot analysis. Expression of ErbB4, a receptor for NRG1, was markedly increased by NRG1-AdMSCs administration, in addition to pMAPK and pAkt, crucial molecules of NRG1-ErbB4 signaling. Taken together, our data suggest that NRG1-AdMSCs can provide excellent therapeutic potential in ischemic stroke by activating NRG1-ErbB4 signaling network.


Subject(s)
Adipose Tissue/cytology , Brain Ischemia/therapy , Mesenchymal Stem Cell Transplantation/methods , Neuregulin-1/therapeutic use , Stroke/therapy , Animals , Blotting, Western , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Humans , MAP Kinase Signaling System , Male , Neuregulin-1/administration & dosage , Neuregulin-1/metabolism , Rats , Rats, Sprague-Dawley
6.
Eur J Pharm Sci ; 134: 256-265, 2019 Jun 15.
Article in English | MEDLINE | ID: mdl-31047968

ABSTRACT

A redox-responsive fluorescent carbon nanogel (FCN) was designed as a bioimaging probe for targeted drug delivery to cancer cells. FCN was synthesized by the carbonization of disulfide cross-linked hyaluronic acid in the fluorescence "on" mode, followed by the attachment of manganese oxide (MnO2) nanosheets for fluorescence quenching (fluorescence "off"). We hypothesized that the fluorescence intensity of paclitaxel (PTX)-MnO2/FCN would suddenly increase (fluorescence "on") in the presence of a high level of glutathione (GSH) in cancer cells, owing to the reduction of MnO2 to Mn2+ and cleavage of the disulfide bond. Consequently, PTX would be released from the FCN system. Consistent with this hypothesis, the designed system recovered FCN fluorescence and triggered drug release through the cleavage of the disulfide bond by GSH. Moreover, PTX-MnO2/FCN demonstrated stable fluorescence intensity after GSH treatment, serving as a potential biosensor. PTX-MnO2/FCN exhibited excellent biocompatibility with normal cells and selectively targeted tumor cells, highlighting the therapeutic capabilities of this system. The developed PTX-MnO2/FCN structure may serve as a smart drug delivery system with diagnostic and therapeutic properties, good selectivity, and compatibility, and with excellent potential for biomedical applications.


Subject(s)
Breast Neoplasms/drug therapy , Drug Delivery Systems/methods , Fluorescence , Manganese Compounds/chemistry , Oxides/chemistry , Paclitaxel/administration & dosage , Animals , Carbon/chemistry , Cell Line, Tumor/cytology , Cell Survival/drug effects , Dogs , Drug Liberation , Glutathione/pharmacology , Hyaluronic Acid/chemistry , Madin Darby Canine Kidney Cells , Nanocomposites/chemistry , Nanoparticles , Oxidation-Reduction , Paclitaxel/pharmacology , Polymers/chemistry
7.
Mol Cancer ; 18(1): 68, 2019 03 30.
Article in English | MEDLINE | ID: mdl-30927911

ABSTRACT

BACKGROUND: Although the tumor stroma in solid tumors like gastric cancer (GC) plays a crucial role in chemo-resistance, specific targets to inhibit the interaction between the stromal and cancer cells have not yet been utilized in clinical practice. The present study aims to determine whether cancer-associated fibroblasts (CAFs), a major component of the tumor stroma, confer chemotherapeutic resistance to GC cells, and to discover potential targets to improve chemo-response in GC. METHODS: To identify CAF-specific proteins and signal transduction pathways affecting chemo-resistance in GC cells, secretome and transcriptome analyses were performed. We evaluated the inhibiting effect of CAF-specific protein in in vivo and in vitro models and investigated the expression of CAF-specific protein in human GC tissues. RESULTS: Secretome and transcriptome data revealed that interleukin-6 (IL-6) is a CAF-specific secretory protein that protects GC cells via paracrine signaling. Furthermore, CAF-induced activation of the Janus kinase 1-signal transducer and activator of transcription 3 signal transduction pathway confers chemo-resistance in GC cells. CAF-mediated inhibition of chemotherapy-induced apoptosis was abrogated by the anti-IL-6 receptor monoclonal antibody tocilizumab in various experimental models. Clinical data revealed that IL-6 was prominently expressed in the stromal portion of GC tissues, and IL-6 upregulation in GC tissues was correlated with poor responsiveness to chemotherapy. CONCLUSIONS: Our data provide plausible evidence for crosstalk between GC cells and CAFs, wherein IL-6 is a key contributor to chemoresistance. These findings suggest the potential therapeutic application of IL-6 inhibitors to enhance the responsiveness to chemotherapy in GC.


Subject(s)
Cancer-Associated Fibroblasts/cytology , Fluorouracil/administration & dosage , Interleukin-6/genetics , RNA, Small Interfering/pharmacology , Stomach Neoplasms/drug therapy , Animals , Cancer-Associated Fibroblasts/drug effects , Cancer-Associated Fibroblasts/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Coculture Techniques , Drug Resistance, Neoplasm/drug effects , Fluorouracil/pharmacology , Humans , Interleukin-6/antagonists & inhibitors , Interleukin-6/metabolism , Mice , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Xenograft Model Antitumor Assays
8.
ChemMedChem ; 13(22): 2437-2447, 2018 11 20.
Article in English | MEDLINE | ID: mdl-30288948

ABSTRACT

In the present study, a pH/redox-responsive cationic polymer dot (CD) was successfully prepared for a near-infrared (NIR)-mediated, simultaneously controllable photothermal temperature guided imaging off/on system to monitor therapeutic delivery. Carbonized disulfide cross-linked branched polyethyleneimine (bPEI) was conjugated with folic acid (FA) as a targeting moiety and partially formed an ionic complex with anionic indocyanine green (ICG) to afford a bPEI-based CD (ICG-CD). This was responsive to mild reductive (glutathione, GSH) and acidic tumor conditions, which enabled the simultaneous biodegradation of those hydrophobic and complex sites. The ICG-CD internalized readily into the cytoplasm of cancer cells by a FA receptor and cationic-mediated endocytosis in the off state, whereas if ICG-CD met intracellular GSH at high concentrations, GSH contributed partially to the recovery of fluorescence and was then internalized into acidic endosomes to induce complete restoration of fluorescence. This tumor-sensitive degradability of the CD not only facilitated ICG release in the tumor location but also allowed controllable photothermal therapy effects of nanoparticles under NIR irradiation, which resulted in improved cancer therapy. Taken together, the results indicate great potential in tumor targeting, intracellular imaging, and controllable therapeutic delivery through a fluorescence off/on assay under the pH/redox conditions of cancer cells.


Subject(s)
Antineoplastic Agents/pharmacology , Fluorescent Dyes/pharmacology , Indocyanine Green/pharmacology , Quantum Dots/chemistry , Animals , Antineoplastic Agents/chemistry , Carbon/chemistry , Cell Line, Tumor , Dogs , Endocytosis/physiology , Endosomes/metabolism , Fluorescence , Fluorescent Dyes/chemistry , Fluorescent Dyes/metabolism , Folate Receptors, GPI-Anchored/metabolism , Folic Acid/chemistry , Folic Acid/metabolism , Glutathione/metabolism , Humans , Hydrogen-Ion Concentration , Hyperthermia, Induced/methods , Indocyanine Green/chemistry , Indocyanine Green/metabolism , Infrared Rays , Madin Darby Canine Kidney Cells , Oxidation-Reduction , Phototherapy/methods , Polyethylene Glycols/chemistry , Polyethylene Glycols/metabolism , Polyethyleneimine/chemistry , Polyethyleneimine/metabolism , Quantum Dots/radiation effects , Theranostic Nanomedicine/methods
9.
Eur J Pharm Biopharm ; 132: 200-210, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30266668

ABSTRACT

Redox-responsive polymer dot (PD) were synthesized from disulfide cross-linked polymers in a carbonized process to allow quenching effects by loading of boron-dipyrromethene (BODIPY) onto the matrix. The disulfide linkage facilitated degradation of the PD system by intracellular glutathione (GSH), leading to fluorescence recovery by BODIPY and intracellular drug release. The paclitaxel release profile showed that approximately 100% of the drug escaped from the matrix in response to 10 mM GSH, whereas less than 10% was released in the absence of GSH. In vitro studies showed that quenching produced by BODIPY loading enabled visual monitoring of cancer cell death, as the quenching disappeared when BODIPY was released by GSH inside of cancer cells. The PD contain disulfide bonds representing a GSH-triggered ligand; thus, nanocarriers presented enhanced in vivo chemotherapeutic inhibition in xenograft tumor-bearing mice localized at the cancer location, guided by fluorescent off-on system tracking and measured by the release of BODIPY. This platform reacts to the redox level in sensitive manner and cancer cell death can be monitored by fluorescence, making this platform useful for bio-applications, particularly in vitro and in vivo therapy and diagnosis, while considering the cell physiological environment. This system may be useful for wider medical applications.


Subject(s)
Antineoplastic Agents, Phytogenic/administration & dosage , Neoplasms/drug therapy , Paclitaxel/administration & dosage , Polymers/chemistry , Animals , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Boron Compounds/chemistry , Cell Line, Tumor , Dogs , Drug Carriers/chemistry , Drug Liberation , Fluorescence Resonance Energy Transfer/methods , Glutathione/metabolism , Humans , Madin Darby Canine Kidney Cells , Mice , Mice, Inbred BALB C , Nanoparticles , Oxidation-Reduction , Paclitaxel/chemistry , Paclitaxel/pharmacology , Xenograft Model Antitumor Assays
10.
J Pharm Biomed Anal ; 159: 1-10, 2018 Sep 10.
Article in English | MEDLINE | ID: mdl-29960038

ABSTRACT

Boronic acid, which can bind chemo-selectively and reversibly to diols, could be used for the early detection of bacteria through its affinity-binding reaction with diol groups on the bacterial cell wall. Herein, we describe the use of a diol-modified fluorescent probe (DYE) conjugated to a nanosensor consisting of phenylboronic acid-functionalized fluorescent carbon dot (FCD) to allow quenching via the Förster resonance energy transfer (FRET) process. Phenylboronic acid is well-known for its preferential affinity for diol-containing molecules through cyclic ester bond formation. Therefore, in the presence of glucose-containing bacteria, the DYE in the cyclic ester form will be released from the FCD and replaced by the bacterial cell forming a new cyclic boronate ester bond with the nanoparticle, inducing recovery of the fluorescence. Quantitatively, the system's detection performance at various bacterial concentrations (101-107 CFU/mL) reached ∼100% after 60 min, indicating that the high binding affinity of the diol moeity on the peptidoglycan (sugar)-rich bacteria was enough to displace the DYE from the boronic acid-functionalized FCD platform. Our facile and tunable fluorescence switch-on system was tested for its ability to detect bacteria in water from a contaminated river. Incredibly, the system was most successful in detecting bacteria in the contaminated river water, thus proving it to be a less expensive and more robust affinity biosensor for the detection of contaminating pathogens in various chemoselective ligand-based environments.


Subject(s)
Biosensing Techniques/methods , Boronic Acids/chemistry , Escherichia coli , Fluorescent Dyes/chemistry , Luminescence , Staphylococcus aureus , Carbon/chemistry , Escherichia coli/isolation & purification , Staphylococcus aureus/isolation & purification , Time Factors
11.
Mol Cancer Res ; 16(10): 1590-1600, 2018 10.
Article in English | MEDLINE | ID: mdl-29866925

ABSTRACT

Discoidin domain receptor 1 (DDR1) is activated by fibrillar (triple-helical) collagens and collagen IV, which are major components of tumor stroma; thus, DDR1 might be a critical mediator of communication between cancer cells and stroma. The aim of this study was to investigate the effect of DDR1 inhibition on stroma-induced peritoneal metastasis in gastric carcinoma. We analyzed by immunohistochemistry the correlation between DDR1 expression and the pattern of recurrence in gastric carcinoma tissues from a previously characterized and established gastric carcinoma patient cohort. We also cocultured human gastric carcinoma cell lines with gastric cancer-associated fibroblasts (CAF) and investigated DDR1 expression and activation. We evaluated CAF-induced tumorigenic properties of gastric carcinoma cell lines and the effect of a DDR1-specific inhibitor in organotypic cultures and in a peritoneal seeding xenograft animal model. The expression of DDR1 in gastric cancer tissues was positively associated with early recurrence (P = 0.043) and a high incidence of peritoneal recurrence (P = 0.036). We confirmed that coculturing with CAFs elevated DDR1 protein expression in gastric carcinoma cell lines and enhanced gastric carcinoma cell line spheroid formation in organotypic cultures in a tumor cell DDR1-dependent manner. Coimplantation of CAFs with gastric carcinoma cells enhanced peritoneal tumor formation in vivo, an effect that was sensitive to pharmacologic inhibition of DDR1.Implications: This study highlights that CAF-induced elevation of DDR1 expression in gastric carcinoma cells enhances peritoneal tumorigenesis, and that inhibition of DDR1 is an attractive strategy for the treatment of gastric carcinoma peritoneal metastasis. Mol Cancer Res; 16(10); 1590-600. ©2018 AACR.


Subject(s)
Carcinoma/genetics , Discoidin Domain Receptor 1/genetics , Peritoneal Neoplasms/genetics , Stomach Neoplasms/genetics , Carcinogenesis/genetics , Carcinoma/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic/genetics , Humans , Neoplasm Metastasis , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/pathology , Peritoneal Neoplasms/pathology , Peritoneal Neoplasms/secondary , Stomach Neoplasms/pathology
12.
ChemMedChem ; 13(14): 1459-1468, 2018 07 18.
Article in English | MEDLINE | ID: mdl-29774663

ABSTRACT

Herein we describe fluorescence resonance energy transfer (FRET) for a pH/redox-activatable fluorescent carbon dot (FNP) to realize "off-on" switched imaging-guided controllable photothermal therapy (PTT). The FNP is a carbonized self-crosslinked polymer that allows IR825 loading (FNP[IR825]) via hydrophobic interactions for cancer therapy. Fluorescence bioimaging was achieved by the internalization of FNP(IR825) into tumor cells, wherein glutathione (GSH) disulfide bonds are reduced, and benzoic imine groups are cleaved under acidic conditions. The release of IR825 from the FNP core in this system may be used to efficiently control PTT-mediated cancer therapy via its photothermal conversion after near-infrared (NIR) irradiation. In vitro and in vivo cellular uptake studies revealed efficient uptake of FNP(IR825) by tumor cells to treat the disease site. In this way we demonstrated in mice that our smart nanocarrier can effectively kill tumor cells under exposure to a NIR laser, and that the particles are biocompatible with various organs. This platform responds sensitively to the exogenous environment inside the cancer cells and may selectively induce the release of PTT-mediated cytotoxicity. Furthermore, this platform may be useful for monitoring the elimination of cancer cells through the fluorescence on/off switch, which can be used for various applications in the field of cancer cell therapy and diagnosis.


Subject(s)
Benzoates/therapeutic use , Coloring Agents/therapeutic use , Delayed-Action Preparations/chemistry , Indoles/therapeutic use , Neoplasms/diagnostic imaging , Neoplasms/therapy , Quantum Dots/chemistry , Animals , Benzoates/administration & dosage , Carbon/chemistry , Cell Line, Tumor , Coloring Agents/administration & dosage , Dogs , Female , Fluorescence Resonance Energy Transfer/methods , Humans , Hydrogen-Ion Concentration , Hyperthermia, Induced/methods , Indoles/administration & dosage , Infrared Rays , Madin Darby Canine Kidney Cells , Mice, Inbred BALB C , Mice, Nude , Optical Imaging/methods , Oxidation-Reduction , Phototherapy/methods
13.
J Mater Chem B ; 6(37): 5992-6001, 2018 Oct 07.
Article in English | MEDLINE | ID: mdl-32254719

ABSTRACT

A specific membrane and nucleus targeted fluorescence OFF-ON-OFF system, using the dodecane/sulfobetaine group of functionalized carbon dots (CD) with a copper ion (Cu2+-CD) based on the presence of pyrophosphate (PPi) molecules and alkaline phosphatase (ALP) activity, for cancer cell detection was designed. The biosensor could be effectively transported from the cytosol to the nucleus in MDAMB cells, but not in MDCK cells due to the response to a change in pH by CD functionalized with zwitterionic groups. The biosensor also showed a membrane-selective regulated route for fusion of long alkyl chain grafted-CD on cell membranes. As a potential sensor, the fluorescence of the prepared Cu2+-CD was significantly quenched due to aggregation. In human cancer MDAMB cells, a nearly complete restoration of the fluorescence intensity of the Cu2+-CD was observed because of the high levels of intracellular PPi, which preferentially bound to Cu2+. After 10 min, in the MDAMB cells, re-quenching of the CD fluorescence occurred because of the high level of intracellular ALP, which can hydrolyze PPi and release the Cu2+ to re-aggregate the CD. In contrast to MDAMB cells, MDCK cells did not show an obvious response to the specific intracellular biomolecules, thus, enabling the biosensor to be used to distinguish between cancer and normal cells. In conclusion, this biosensor has the potential to be a simple and sensitive cancer diagnostic tool that can differentiate normal cells from cancer cells on coated surfaces and in aqueous states.

14.
Anal Chem ; 89(24): 13508-13517, 2017 12 19.
Article in English | MEDLINE | ID: mdl-29137454

ABSTRACT

The tumor-specific sensitive fluorescence sensing of cellular alkaline phosphatase (ALP) activity on the basis of host-guest specific and pH sensitivity was conducted on coated surfaces and aqueous states. Cross-linked fluorescent nanoparticles (C-FNP) consisting of ß-cyclodextrin (ß-CD)/boronic acid (BA) and fluorescent hyaluronic acid [FNP(HA)] were conjugated to fluorescent polydopamine [FNP(pDA)]. To determine the quenching effect of this system, hydrolysis of 4-nitrophenyl phosphate (NPP) to 4-nitrophenol (NP) was performed in the cavity of ß-CD in the presence of ALP activated photoinduced electron transfer (PET) between NP and C-FNP. At an ALP level of 30-1000 U/L, NP caused off-emission of C-FNP because of their specific host-guest recognition. Fluorescence can be recovered under pH shock due to cleavage of the diol bond between ß-CD and BA, resulting in release of NP from the fluorescent system. Sensitivity of the assays was assessed by confocal imaging not only in aqueous states, but also for the first time on coated surfaces in MDAMB-231 and MDCK cells. This novel system demonstrated high sensitivity to ALP through generation of good electron donor/acceptor pair during the PET process. Therefore, this fluorescence sensor system can be used to enhance ALP monitoring and cancer diagnosis on both coated surfaces and in aqueous states in clinical settings.


Subject(s)
Alkaline Phosphatase/metabolism , Carbon/chemistry , Cross-Linking Reagents/chemistry , Fluorescent Dyes/chemistry , Indoles/chemistry , Nanoparticles/chemistry , Polymers/chemistry , Animals , Cell Line, Tumor , Dogs , Fluorescence , Humans , Hydrogen-Ion Concentration , Madin Darby Canine Kidney Cells , Nitrophenols/chemistry , Nitrophenols/metabolism , Organophosphorus Compounds/chemistry , Organophosphorus Compounds/metabolism , Particle Size , Solutions , Surface Properties , Water/chemistry , beta-Cyclodextrins/chemistry , beta-Cyclodextrins/metabolism
15.
ACS Appl Mater Interfaces ; 9(38): 33317-33326, 2017 Sep 27.
Article in English | MEDLINE | ID: mdl-28876888

ABSTRACT

The ability to quickly detect and kill bacteria is crucial in the realm of antibiotic resistance. In this study, we synthesized a detection probe consisting of polyethylenimine (PEI)-passivated polydopamine-based fluorescent carbon (FDA:PEI) nanoparticles, generating a cationic adhesive material for bacterial detection that is surface-coatable, photothermal, and antibacterial. The cationic FDA:PEI nanoparticles effectively bound to the anionic bacterial cell wall, resulting in a dramatic quenching effect visible in fluorescence spectra and confocal images. In this fluorescence on/off system, FDA:PEI nanoparticles showed similar bacterial detection abilities between aqueous- and solid-phase assays. Scanning electron microscopy clearly showed the attachment of FDA:PEI nanoparticles to the surface of bacteria, both in solution and as a coating on the surface of a polypropylene film. In addition to detection, this versatile material was found to have an antibacterial potential, via near-infrared irradiation to induce a heat release, killing bacteria by thermolysis. Thus, by exploiting the cationic and catechol moieties on the surface of polydopamine carbon dots, we developed a novel bacterial-detection platform that can be used in a broad range of conditions.


Subject(s)
Nanoparticles , Anti-Bacterial Agents , Bacteria , Coloring Agents , Polyethyleneimine
16.
BMC Fam Pract ; 18(1): 4, 2017 Jan 17.
Article in English | MEDLINE | ID: mdl-28095788

ABSTRACT

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death globally. However, many individuals are unaware of their CVD risk factors. The objective of this systematic review is to determine the effectiveness of existing intervention strategies to increase uptake of CVD risk factors screening. METHODS: A systematic search was conducted through Pubmed, CINAHL, EMBASE and Cochrane Central Register of Controlled Trials. Additional articles were located through cross-checking of the references list and bibliography citations of the included studies and previous review papers. We included intervention studies with controlled or baseline comparison groups that were conducted in primary care practices or the community, targeted at adult populations (randomized controlled trials, non-randomized trials with controlled groups and pre- and post-intervention studies). The interventions were targeted either at individuals, communities, health care professionals or the health-care system. The main outcome of interest was the relative risk (RR) of screening uptake rates due to the intervention. RESULTS: We included 21 studies in the meta-analysis. The risk of bias for randomization was low to medium in the randomized controlled trials, except for one, and high in the non-randomized trials. Two analyses were performed; optimistic (using the highest effect sizes) and pessimistic (using the lowest effect sizes). Overall, interventions were shown to increase the uptake of screening for CVD risk factors (RR 1.443; 95% CI 1.264 to 1.648 for pessimistic analysis and RR 1.680; 95% CI 1.420 to 1.988 for optimistic analysis). Effective interventions that increased screening participation included: use of physician reminders (RR ranged between 1.392; 95% CI 1.192 to 1.625, and 1.471; 95% CI 1.304 to 1.660), use of dedicated personnel (RR ranged between 1.510; 95% CI 1.014 to 2.247, and 2.536; 95% CI 1.297 to 4.960) and provision of financial incentives for screening (RR 1.462; 95% CI 1.068 to 2.000). Meta-regression analysis showed that the effect of CVD risk factors screening uptake was not associated with study design, types of population nor types of interventions. CONCLUSIONS: Interventions using physician reminders, using dedicated personnel to deliver screening, and provision of financial incentives were found to be effective in increasing CVD risk factors screening uptake.


Subject(s)
Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Mass Screening/statistics & numerical data , Primary Prevention/organization & administration , Adult , Aged , Family Practice/organization & administration , Female , Humans , Male , Middle Aged , Needs Assessment , Randomized Controlled Trials as Topic , Reproducibility of Results , Risk Assessment , Risk Factors
17.
Malays Fam Physician ; 12(3): 18-24, 2017.
Article in English | MEDLINE | ID: mdl-29527275

ABSTRACT

INTRODUCTION: There are limited studies conducted on the needs of cancer survivors in developing countries like Malaysia. This qualitative study aimed at exploring the post-treatment impact and needs of prostate cancer survivors. METHODS: A qualitative study design was used. One in-depth interview and four focus group discussions were conducted with 24 prostate cancer survivors (age range: 58-79 years) from government and private hospitals in Malaysia in 2013. Trained researchers used a topic guide to guide the interviews, which were audio-recorded, transcribed verbatim, checked and managed with Nvivo 10 software. A thematic approach was used to analyse the data. RESULTS: Three main themes emerged from the analysis: (a) impact of prostate cancer on the survivors, (b) support needed for coping and (c) information needs. Prostate cancer has an important impact on the survivors' lifestyle after treatment. Some of them have to live with the post-treatment side effects. They were anxious about the possibility of relapse. In addition to family and peer support, there were participants who felt that spiritual support was important in helping them cope with the possibility of relapse. The survivors felt that they did not receive enough information about post-treatment care, dietary measures and supplements for relapse prevention, treatment and prognosis. CONCLUSION: Prostate cancer has a significant impact on the survivor's lifestyle, emotional and physical health. They need information and emotional support from the healthcare professionals, family and peers. Therefore, it is important for healthcare providers to explore the needs of prostate cancer survivors and provide the necessary support.

18.
J Mater Chem B ; 5(34): 7099-7108, 2017 Sep 14.
Article in English | MEDLINE | ID: mdl-32263900

ABSTRACT

We describe a novel synthesis method for silica nanoparticles, which involves a combination of these nanoparticles with targetable and nontargetable fluorescent dopamine-conjugated hyaluronic acid (HA-DA) via rational chemical dehydration. The resulting HA-decorated silica fluorescent nanoparticles, electrostatically linked to polyaniline (PANI) to form ionic complexes, possessed high fluorescence intensity and were monodisperse in solution, near-infrared light responsive, and amenable to specific labeling of cancer cell lines. When exposed to near-infrared irradiation, the fluorescent silica nanoparticles exerted photothermal cytotoxicity guided by bioimaging and distinguished malignant cancer cells from normal cells via receptor CD44. Different heating properties of nanoparticles depend on local interactions between different structures, and determination of their efficacy could lead to new thermal treatment options such as noninvasive photothermal therapy.

19.
Malays Fam Physician ; 10(1): 19-25, 2015.
Article in English | MEDLINE | ID: mdl-26425291

ABSTRACT

INTRODUCTION: Hypertension is highly prevalent in the older people. Chronic disease care is a major burden in the public primary care clinics in Malaysia. Good blood pressure (BP) control is needed to reduce the morbidity and mortality of cardiovascular disease (CVD). This study aimed to determine the status of BP control and its associated factors among older people with hypertension in public primary care clinics. MATERIALS AND METHODS: A cross-sectional study on hypertensive patients aged 18 years and above was conducted in six public primary care clinics in Federal Territory, Malaysia. A total of 1107 patients were selected via systematic random sampling. Data from 441 (39.8%) patients aged 60 years and more were used in this analysis. BP control was determined from the average of two BP readings measured twice at an interval of 5 min. For patients without diabetes, poor BP control was defined as BP of ≥140/90 mm Hg and ≥150/90 for the patients aged 80 years and more. For patients with diabetes, poor control was defined as BP of ≥140/80 mm Hg. RESULTS: A total of 51.7% (n = 228) of older patients had poor BP control. The factors associated with BP control were education level (p = 0.003), presence of comorbidities (p = 0.015), number of antihypertensive agents (p = 0.001) and number of total medications used (p = 0.002). Patients with lower education (less than secondary education) (OR = 1.7, p = 0.008) and the use of three or more antihypertensive agents (OR = 2.0, p = 0.020) were associated with poor BP control. CONCLUSION: Among older people with hypertension, those having lower education level, or using three or more antihypertensive agents would require more attention on their BP control.

20.
Malays Fam Physician ; 10(2): 36-44, 2015.
Article in English | MEDLINE | ID: mdl-27099659

ABSTRACT

INTRODUCTION: Hill-Bone compliance to high blood pressure therapy scale (HBTS) is one of the useful scales in primary care settings. It has been tested in America, Africa and Turkey with variable validity and reliability. The aim of this paper was to determine the validity and reliability of the Malay version of HBTS (HBTS-M) for the Malaysian population. MATERIALS AND METHODS: HBTS comprises three subscales assessing compliance to medication, appointment and salt intake. The content validity of HBTS to the local population was agreed through consensus of expert panel. The 14 items used in the HBTS were adapted to reflect the local situations. It was translated into Malay and then back-translated into English. The translated version was piloted in 30 participants. This was followed by structural and predictive validity, and internal consistency testing in 262 patients with hypertension, who were on antihypertensive agent(s) for at least 1 year in two primary healthcare clinics in Kuala Lumpur, Malaysia. Exploratory factor analyses and the correlation between HBTS-M total score and blood pressure were performed. The Cronbach's alpha was calculated accordingly. RESULTS: Factor analysis revealed a three-component structure represented by two components on medication adherence and one on salt intake adherence. The Kaiser-Meyer-Olkin statistic was 0.764. The variance explained by each factors were 23.6%, 10.4% and 9.8%, respectively. However, the internal consistency for each component was suboptimal with Cronbach's alpha of 0.64, 0.55 and 0.29, respectively. Although there were two components representing medication adherence, the theoretical concepts underlying each concept cannot be differentiated. In addition, there was no correlation between the HBTS-M total score and blood pressure. CONCLUSION: HBTS-M did not conform to the structural and predictive validity of the original scale. Its reliability on assessing medication and salt intake adherence would most probably to be suboptimal in the Malaysian primary care setting.

SELECTION OF CITATIONS
SEARCH DETAIL
...